Datashee
t
○Product structure：Silicon monolithic integrated circuit ○This product has not designed protection against radioactive rays
. 1/75
TSZ02201-0C1C0E900060-1-2
© 2016 ROHM Co., Ltd. All rights reserved.
10.Jun.2016 Rev.003
TSZ22111・14・001
www.rohm.com
Middle Power Class-D Speaker Amplifier series
20W+20W
Full Digital Speaker Amplifier
with built-in DSP
BM28720MUV
General Description
BM28720MUV is a Full Digital Speaker Amplifier with
built-in DSP (Digital Sound Processor) designed for
Flat-panel TVs in particular for space-saving and
low-power consumption, delivers an output power of
20W+20W. This IC employs Bipolar, CMOS, and
DMOS (BCD) process technology that eliminates
turn-on resistance in the output power stage and
internal loss due to line resistances up to an ultimate
level. With this technology, the IC can achieve high
efficiency. In addition, the IC is packaged in a compact
reverse heat radiation type power package to achieve
low power consumption and low heat generation and
eliminates necessity of external heat-sink up to a total
output power of 40W. This product satisfies both needs
for drastic downsizing, low-profile structures and many
function, high quality playback of sound system.
Key Specifications
■ Supply voltage (VCC)
■ Speaker output power
(VCC=18.5V, RL=8Ω)
■ THD+N
10V to 24V
20W+20W (Typ.)
0.07 [%] (Typ.)
Applications
■ Flat Panel TVs (LCD, OEL)
■ Home Audio
■ Desktop PC
■ Amusement equipments
■ Electronic Music equipments, etc.
Package W(Typ) x D(Typ) x H(Max)
VQFN032V5050 5.00mm x 5.00mm x 1.00mm
Features
■ This IC includes the DSP (digital sound processor)
for Audio signal processing for Flat TVs.
12 Band/ch BQ, 3 Band DRC, Pre-Scaler,
Channel Mixer, Fine Master Volume,
Hard Clipper, Level Meter etc.
■ This IC has one input systems of digital audio
interface. (No needs of Master Clock)
- I2S / LJ / RJ format
- LRCLK: 32k/44.1k/48KHz
- BCLK: 32fs / 48fs / 64fs
- SDATA: 16 / 20 / 24bit
■ This IC has one output systems of digital audio
interface.
- I2S format
- SDATA: 16 / 20 / 24bit
■ With wide range of power supply voltage.
■ The monaural output that can reduce the number of
external parts can be used.
■ With high efficiency and low heat dissipation
contributing to miniaturization, slim design, and also
power saving of the system.
■ Eliminates pop-noise generated during the power
supply on/off. High quality muting performance is
realized by using the soft-muting technology.
■ This IC is built-in with various protection functions
for highly reliability design.
- High temperature protection
- Under voltage protection
- Output short protection
- DC voltage protection
- Clock stop protection
■ Small package
Typical Application Circuit
VQFN032V5050
Figure 1. Typical application circuits
SCL
SDA
BCLK
LRCLK
RSTX
SDATA
Digital
Audio
Source
MCU
MUTEＸ
ERROR
SP ch1
(Lch)
SP ch2
(Rch)
OUT1P
OUT1N
OUT2P
OUT2N
BSP2P
BSP1P
BSP1N
BSP2N
SDATAO
2/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Pin configuration and Block diagram
1514131211109
1
2
3
4
5
6
7
8
32 31 30 29 28 27 26 25
24
23
22
21
20
19
18
17
16
BSP1P
GNDP1
REG_G
Driver
FET 2N
VCCP2
GNDP2
Driver
FET 2P
PWM
Modulator
Control
I/F
Protection
2 wire I/F
SDATAO
Audio
DSP
I2S/LJ/RJ
I/F
DGND
8 Times
Over-
Sampling
Digital
Filter
REG15
DVDD
PLL
SCL
SDA
ADDR
SDATA
LRCLK
PLL
ERROR OUT2N
OUT2P
BSP1N
OUT1P
MUTEX
RSTX
NC
BSP2N
BSP2P
NC
OUT1N
VCCP1
BCLK
TEST3TEST2
TEST1
Driver
FET 1P
Driver
FET 1N
Figure 2. Pin configurations and Block diagram (Top View)
Pin Description
No.
Name
I/O
No.
Name
I/O
No.
Name
I/O
No.
Name
I/O
1
ADDR
I
9
TEST2
I
17
VCCP2
-
25
OUT1P
O
2
BCLK
I
10
DVDD
-
18
GNDP2
-
26
BSP1P
I
3
LRCK
I
11
TEST3
I
19
BSP2P
I
27
REG_G
O
4
SDATA
I
12
SDATAO
O
20
OUT2P
O
28
NC
-
5
TEST1
I
13
ERROR
O
21
OUT1N
O
29
RSTX
I
6
PLL
-
14
NC
-
22
BSP1N
I
30
MUTEX
I
7
REG15
O
15
BSP2N
I
23
GNDP1
-
31
SCL
I
8
DGND
-
16
OUT2N
O
24
VCCP1
-
32
SDA
I/O
I = input; O = output; - = others
3/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Absolute Maximum Ratings (Ta=25℃)
Item
Symbol
Limit
Unit
Conditions
Supply voltage
VCC
-0.3 to 34
V
Pin 17, 24 (Note 1) (Note 2)
DVDD
-0.3 to 4.5
V
Pin 10 (Note 1)
Power dissipation
Pd
3.26
W
(Note 3)
4.56
W
(Note 4)
Input voltage 1
VIN1
-0.3 to
DVDD+0.3
V
Pin 1 - 5, 9, 11, 12, 13, 29 -32 (Note 1)
Terminal voltage 1
VPIN1
-0.3 to 7.0
V
Pin 27 (Note 1)
Terminal voltage 2
VPIN2
-0.3 to 29
V
Pin 16, 20, 21, 25 (Note 1)(Note 5)
Terminal voltage 3
VPIN3
OUTxx+6.0
V
Pin 15, 19, 22, 26 (Note 1)
Operating temperature range
Topr
-25 to +85
℃
Storage temperature range
Tstg
-55 to +150
℃
Maximum junction temperature
Tjmax
+150
℃
(Note 1) The voltage that can be applied reference to GND (Pin 8, 18, 23).
(Note 2) Do not exceed Pd and Tjmax=150℃.
(Note 3) 74.2mm × 74.2mm × 1.6mm, FR4, 4-layer glass epoxy board
(Top and bottom layer back copper foil size: 20.2mm2, 2nd and 3rd layer back copper foil size: 5505mm2)
Derating in done at 26.1 mW/℃ for operating above Ta＝25℃. There are thermal via on the board.
(Note 4) 74.2mm × 74.2mm × 1.6mm, FR4, 4-layer glass epoxy board (Copper area 5505mm2)
Derating in done at 36.5 mW/℃ for operating above Ta＝25℃. There are thermal via on the board.
(Note 5) It should use it below this ratings limit including the AC peak waveform (overshoot) for all conditions.
At only undershoot, it is admitted using at ≦10ns and ≦29V by the VCC reference. (Please refer following figure.)
Recommended Operating Ratings (Ta=25℃)
Item
Symbol
Limit
Unit
Conditions
Supply voltage
VCC
10 to 24
V
Pin 17, 24 (Note 1) (Note 2)
DVDD
3 to 3.6
V
Pin 10 (Note 1)
Minimum load impedance
RL
5.4
Ω
Pin 16, 20, 21, 25
VCC = 18V to 24V (Note 6)
3.6
Ω
Pin 16, 20, 21, 25
VCC < 18V (Note 6)
(Note 6) Do not exceed Pd.
GND
VCC
≦10ns
Overshoot to GND
29V (Max.) Undershoot from
VCC
29V(Max.)
Figure 3.
4/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Electrical Characteristics
(Unless otherwise specified Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz, RL=8Ω,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Item
Symbol
Limit
Unit
Conditions
Min
Typ
Max
Total circuit
Circuit current 1
(Normal mode)
ICC1
-
45
90
mA
Pin 17, 24, No load
IDD1
-
9
19
mA
Pin 10, -infinity dBFS input, No load
Circuit current 2
(Reset mode)
ICC2
-
10
40
μA
Pin 17, 24, No load
RSTX=0V, MUTEX=0V
IDD2
-
2.5
7.0
mA
Pin 10, -infinity dBFS input, No load
RSTX=0V, MUTEX=0V
Open-drain terminal
Low level voltage
VERR
-
-
0.8
V
Pin 13, IO=0.5mA
Regulator output voltage 1
VREG_G
4.9
5.7
6.5
V
Pin 27
Regulator output voltage 2
VREG15
1.3
1.5
1.7
V
Pin 7
High level input voltage
VIH
2.5
-
3.3
V
Pin 1 - 5, 9, 11, 29 -32
Low level input voltage
VIL
0
-
0.8
V
Pin 1 - 5, 9, 11, 29 -32
Input current
(Input pull-up terminal)
IUP
-150
-100
-50
μA
Pin 2 – 4 VIN = 0V
Input current
(Input pull-down terminal)
IDN
35
70
105
μA
Pin 1, 29, 30, VIN = 3.3V
Input current
(SCL, SDA terminal)
IIL
-1
0
-
μA
Pin 31, 32, VIN = 0V
Input current
(SCL, SDA terminal)
IIH
-
0
1
μA
Pin 31, 32, VIN = 3.3V
Speaker amplifier output
Maximum output power 1
PO1
-
10
-
W
VCC=13V,THD+N=10%
(Note 7)
Maximum output power 2
PO2
-
20
-
W
VCC=18.5V,THD+N=10%
(Note 7)
Total harmonic distortion 1
THD1
-
0.07
-
%
PO=1W, AES17
(Note 7)
Crosstalk 1
CT1
60
80
-
dB
VCC=13V, PO=1W, A-weighted
(Note 7)
Output noise voltage 1
VNO1
-
80
-
μVrms
-infinity dBFS input, A-weighted
(Note 7)
PWM sampling frequency
fPWM1
-
256
-
kHz
fs=32 kHz
fPWM2
-
352.8
-
kHz
fs=44.1 kHz
fPWM3
-
384
-
kHz
fs=48 kHz
(Note 7) These items show the typical performance of device and depend on board layout, parts, and power supply.
The standard value is in mounting device and parts on surface of ROHM’s board directly.
5/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=0V/3.3V, MUTEX=0V/3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 4.
Figure 6.
Figure 7.
Power supply voltage- Current consumption
Output power - Efficiency
Output power - Current consumption
Figure 5.
Power supply voltage- Current consumption
0
2
4
6
8
10
12
14
6 8 10 12 14 16 18 20 22 24 26 28 30
VCC [V]
ICC [A]
0
10
20
30
40
50
60
6 8 10 12 14 16 18 20 22 24 26 28 30
VCC [V]
ICC [mA]
RSTX=H
RL=8Ω
No Signal
MUTEX=H
MUTEX=L
RSTX=MUTEX=L
RL=8Ω
No Signal
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0 5 10 15 20
Output Power [W/CH]
ICC [A]
0
10
20
30
40
50
60
70
80
90
100
0 5 10 15 20
Output Power [W/CH]
Efficiency [%]
RL=8Ω
RL=6Ω
RL=4Ω
RL=8Ω
RL=6Ω
RL=4Ω
6/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 10.
Figure 11.
Waveform at soft start
Waveform at soft mute
Output voltage - Power voltage (RL=8Ω)
Output power - Current consumption (RL=8Ω)
Figure 8.
Figure 9.
※Dotted line means internal dissipation is over package power.
RL=8Ω
Po=1W
RL=8Ω
Po=1W
0
5
10
15
20
25
30
35
40
45
6 8 10 12 14 16 18 20 22 24 26 28 30
VCC [V]
Output Power [W/CH]
THD+N=10%
THD+N=1%
RL=8Ω
0
0.5
1
1.5
2
2.5
010 20 30 40
Output Power [W/CH]
ICC [A]
VCC=18V
RL=8Ω
7/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
0
5
10
15
20
25
30
35
40
45
6 8 10 12 14 16 18 20 22 24 26 28 30
VCC [V]
Output Power [W/CH]
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Output power - Current consumption (RL=6Ω)
Output voltage - Power voltage (RL=6Ω)
Output power - Current consumption (RL=4Ω)
※Dotted line means internal dissipation is over package power.
Output Voltage – Power Voltage (RL=4Ω)
0
5
10
15
20
25
30
35
40
45
6 8 10 12 14 16 18 20 22 24 26 28 30
VCC [V]
Output Power [W/CH]
THD+N=10%
THD+N=1%
RL=6Ω
0
0.5
1
1.5
2
2.5
3
3.5
010 20 30 40
Output Power [W/CH]
ICC [A]
VCC=18V
RL=6Ω
THD+N=10%
THD+N=1%
RL=4Ω
0
0.5
1
1.5
2
2.5
3
3.5
010 20 30 40
Output Power [W/CH]
ICC [A]
VCC=18V
RL=4Ω
8/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(RL=8Ω, Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
0.001
0.01
0.1
1
10
10 100 1k 10k 100k
Frequency [Hz]
THD+N [%]
0.01
0.1
1
10
100
0.01 0.1 1 10 100
Po [W]
THD+N [%]
Figure 16.
Figure 17.
Figure 18.
Figure 19.
FFT of output noise voltage
Frequency – Output power
Output Power - THD+N
Frequency - THD+N
-10
-5
0
5
10
10 100 1k 10k 100k
Frequency [Hz]
Voltage Gain [dBrA]
-140
-120
-100
-80
-60
-40
-20
0
10 100 1k 10k 100k
Frequency [Hz]
Noise FFT [dBV]
OUT1
OUT2
No Signal
B.W. none
RL=8Ω
OUT1
OUT2
Po=1W=0dB
B.W. none
RL=8Ω
AES17
RL=8Ω
f=1kHz
f=100Hz
f=6kHz
AES17
Po=1W
RL=8Ω
OUT1
OUT2
9/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(RL=8Ω, Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 20.
Frequency - Crosstalk
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1k 10k 100k
Frequency [Hz]
Crosstalk [dB]
Po=1W
RL=8Ω
OUT1
OUT2
10/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(RL=6Ω, Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 21.
Figure 22.
Figure 23.
Figure 24.
FFT of output noise voltage
Frequency – Output power
Output Power - THD+N
Frequency - THD+N
-140
-120
-100
-80
-60
-40
-20
0
10 100 1k 10k 100k
Frequency [Hz]
Noise FFT [dBV]
-10
-5
0
5
10
10 100 1k 10k 100k
Frequency [Hz]
Voltage Gain [dB]
OUT1
OUT2
No Signal
B.W. none
RL=6Ω
OUT1
OUT2
Po=1W=0dB
B.W. none
RL=6Ω
0.01
0.1
1
10
100
0.01 0.1 1 10 100
Po [W]
THD+N [%]
0.001
0.01
0.1
1
10
10 100 1k 10k 100k
Frequency [Hz]
THD+N [%]
AES17
RL=6Ω
f=1kHz
f=100Hz
f=6kHz
AES17
Po=1W
RL=6Ω
OUT1
OUT2
11/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output RL=6Ω, Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 25.
Frequency - Crosstalk
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1k 10k 100k
Frequency [Hz]
Crosstalk [dB]
Po=1W
RL=6Ω
OUT1
OUT2
12/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(RL=4Ω, Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 26.
Figure 27.
Figure 28.
Figure 29.
FFT of output noise voltage
Frequency – Output power
Output Power - THD+N
Frequency - THD+N
-140
-120
-100
-80
-60
-40
-20
0
10 100 1k 10k 100k
Frequency [Hz]
Noise FFT [dBV]
OUT1
OUT2
No Signal
B.W. none
RL=4Ω
0.01
0.1
1
10
0.01 0.1 1 10 100
Po [W]
THD+N [%]
AES17
RL=4Ω
f=1kHz
f=100Hz
f=6kHz
-10
-5
0
5
10
10 100 1k 10k 100k
Frequency [Hz]
Voltage Gain [dB]
OUT1
OUT2
Po=1W=0dB
B.W. none
RL=4Ω
0.001
0.01
0.1
1
10
10 100 1k 10k 100k
Frequency [Hz]
THD+N [%]
AES17
Po=1W
RL=4Ω
OUT1
OUT2
13/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Typical Performance Curves
Speaker output(RL=4Ω, Ta=25℃, VCC=18V, DVDD=3.3V, RSTX=3.3V, MUTEX=3.3V, f=1kHz,
DSP : Through, fs=48kHz, Snubber circuit for output terminal : Rsnb=5.6Ω, Csnb=680pF)
Measured by ROHM designed 4 layer board.
Figure 30.
Frequency - Crosstalk
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1k 10k 100k
Frequency [Hz]
Crosstalk [dB]
Po=1W
RL=4Ω
OUT1
OUT2
14/75
BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Digital Block Functional Overview
No.
Function
Specification
1
Pre-Scaler
・Lch / Rch become same set point.
・+48dB to -79dB (0.5dB step),-∞dB
2
Channel Mixer
・Lch <= Mute, Lch(default), Rch, (L+R)/2, L-R
・Rch <= Mute, Lch, Rch(default), (L+R)/2, L-R
・Lch/Rch are independent phase reversal control available
3
12 Band BQ
・12 Band biquad type filter
・Only 5 coefficient is required.(b0,b1,b2,a1,a2)
・The Filter types which can be realized is
Peaking/Low-shelf/High-shelf/Low-pass/High-pass/All-pass/Notch.
・Lch/Rch become same set point or independent set. There is soft transition function.
4
Fine Master Volume
・Lch / Rch become same set point or independent set.
・+24dB to -103dB (0.125dB step),-∞dB
・There is soft transition function
5
3 Band DRC
・Non clip output is achieved
・Available three band operation
・Threshold level : +12dB to -32dB (0.5dB step)
6
Post-Scaler
・Lch / Rch become same set point
・+48dB to -79dB (0.5dB step),-∞dB
7
Fine Post-Scaler
・Lch / Rch become independent set point
・+0.7dB to -0.8dB (0.1dB step)
8
DC Cut HPF
・Fc : 1Hz
9
Clipper
・Lch / Rch become same set point
・Clip level : +3dB to -22.5dB (-0.1dB step)
Figure 31. DSP Block diagram
Input1 Main
Pre
Scaler
Fine
Master
Volume/
ch
Fine
Post
Scaler/
ch
DC Cut
HPF Hard
Clipper
I2S
LJ
RJ
3Band
DRC
Channel
Mixer Post
Scaler
12Band
/ch BQ
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TSZ22111 • 15 • 001
RSTX pin, MUTEX pin function
RSTX
(29pin)
MUTEX
(30pin)
DSP block
condition
Speaker output
condition
Low
Low
Reset ON
HiZ_low
(Low consumption)
High
Low
Normal operation
(Mute ON)
HiZ_low(Note 4)
(Mute ON)
High
High
Normal operation
(Mute OFF)
Normal operation
(Mute OFF)
Low
High
Don’t use.
(Note 1) RSTX is set to low, internal registers are initialized.
(Note 2) VCCP1, VCCP2< 2.5V, IC latched by protection circuit and ERROR terminal condition are initialized.
(Note 3) If DVDD is under 3V, RSTX is set to low once for 10ms(min), and set high again. Then DSP is needed to set parameter again.
(Note 4) Speaker output becomes HiZ-low after elapse of PWM stop time after setting MUTEX low. Please refer to PWM sampling frequency.
PWM sampling frequency
PWM sampling frequency of Speaker output and Soft-mute transition time depends on sampling frequency (fs) of the digital
sound input. These transition times are changed by sending select address 0x15[1:0].
Sampling
frequency (fs)
PWM frequency
0x15[1:0]
value
Soft mute transition time
PWM stop time
Mute ON
Mute OFF
48kHz
384kHz
0x0
10.7ms
10.7ms
86ms
0x1
21.4ms
10.7ms
106ms
0x2
42.7ms
10.7ms
125ms
0x3
85.4ms
10.7ms
162ms
44.1kHz
352.8kHz
0x0
11.7ms
11.7ms
93ms
0x1
23.3ms
11.7ms
113ms
0x2
46.5ms
11.7ms
135ms
0x3
92.9ms
11.7ms
177ms
32 kHz
256kHz
0x0
16.1ms
16.1ms
116ms
0x1
32.1ms
16.1ms
148ms
0x2
64.1ms
16.1ms
178ms
0x3
128.1ms
16.1ms
241ms
Wait time(Twait) rules from releasing RSTX to releasing MUTEX.
When the time from releasing RSTX to releasing MUTEX prescribes Twait, please secure Twait by all means more than
450ms.
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TSZ22111 • 15 • 001
2 wire Bus control signal specification
1) Electrical characteristics and Timing of Bus line and I/O stage
SDA and SCL bus line characteristics(Unless otherwise specified Ta=25℃, VDD=3.3V)
Parameter
Symbol
High speed mode
Unit
Min.
Max.
1
SCL clock frequency
fSCL
0
400
kHz
2
Bus free time between「Stop」condition and「Start」
condition
tBUF
1.3
－
μs
3
Hold-time of (sending again)「Start」condition. After this
period the first clock pulse is generated.
tHD;STA
0.6
－
μs
4
SCL clock’s LOW state Hold-time
tLOW
1.3
－
μs
5
SCL clock’s HIGH state Hold-time
tHIGH
0.6
－
μs
6
Set-up time of sending again「Start」condition
tSU;STA
0.6
－
μs
7
Data hold time
tHD;DAT
0 (Note 1)
－
μs
8
Data set-up time
tSU;DAT
250
－
ns
9
Rise-time of SDA and SCL signal
tR
20+0.1Cb
300
ns
10
Fall-time of SDA and SCL signal
tF
20+0.1Cb
300
ns
11
Set-up time of 「Stop」condition
tSU;STO
0.6
－
μs
12
Capacitive load of each bus line
Cb
－
400
pF
The above-mentioned numerical values are all the values corresponding to VIH min and the VIL max level.
(Note 1) To exceed an undefined area on the fall-edge of SCL (VIH min of the SCL signal), the transmitting set should internally
offer the holding time of 300ns or more for the SDA signal.
(Note 2) SCL and SDA pin is not corresponding to threshold tolerance of 5V.
Please use it within 4.5V of the absolute maximum rating.
2)Command interface
2 wire Bus control is used for command interface. It not only writes but also it is possible to read it excluding a part of
register. In addition to “Slave Address “ , set and write 1 byte of “Select Address “ to read out the data. 2 wire Bus Slave
mode format is illustrated below.
MSB LSB MSB LSB MSB LSB
S
Slave Address
A
Select Address
A
Data
A
P
S ： Start Condition
Slave Address ： The data of eight bits in total is sent putting up bit of Read mode (high) or Write mode (low) after slave
address (7bit) set with the terminal ADDR. (MSB first)
A ： The acknowledge bit adds to data that the acknowledge is sent and received in each byte.
When data is correctly sent and received, “low” is sent and received.
There was no acknowledgement for “high”.
Select Address ：The select address in one byte is used.(MSB first)
Data ： Data byte is sent and received data(MSB first)
P ： Stop Condition
tBUF
tLOW tR
tHD;STA
SP
tHD;DAT
tF
tHIGH tSU;DAT tSU;STA
Sr
tHD;STA
tSU;STO
P
SDA
SCL
Figure 32.
Figure 33.
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TSZ22111 • 15 • 001
3)Slave Address
・While ADDR pin is “low”
MSB LSB
A6
A5
A4
A3
A2
A1
A0
R/W
1
0
0
0
0
0
0
1/0
・While ADDR pin is “high”
MSB LSB
A6
A5
A4
A3
A2
A1
A0
R/W
1
0
0
0
0
0
1
1/0
4) Writing of data
・Basic format
S
Slave Address
A
Select Address
A
Data
A
P
： Master to Slave, ： Slave to Master
・Auto-increment format
S
Slave Address
A
Select Address
A
Data 1
A
Data 2
A
Data 3…N
A
P
： Master to Slave, ： Slave to Master
5)Reading of data
First of all, the destination address (0x20 in the example) for reading is written in the register of the 0xD0 address at the
time of reading. In the following stream, data is read after the slave address. Please do not return acknowledge when you
end the reception.
S
Slave Address
A
Req_Addr
A
Select Address
A
P
(ex.) 0x80 0xD0 0x20
S
Slave Address
A
Data 1
A
Data 2
A
A
Data N
Ā
P
(ex.) 0x81 0x** 0x** 0x**
： Master to Slave， ： Slave to Master，A：With Acknowledge，Ā：Without Acknowledge
SDA
SCL
MSB 6 5 LSB
Start Condition
SDA↓ SCL=”high”Stop condition
SDA↑ SCL=”high”
Figure 34.
Figure 35.
Figure 36.
Figure 37.
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TSZ22111 • 15 • 001
Format of digital audio input
・LRCLK: It is L/R clock input signal.
It corresponds to 32kHz/44.1kHz/48kHz and that is same as the sampling frequency (fs).
This signal shows left or right of audio data.
・BCLK: It is Bit Clock input signal.
It is used for the latch of data in rising edge. Frequency of BCLK is 64 times of sampling frequency (64fs) or 48 times
(48fs) or 32 times (32fs). If BCLK frequency is 32fs, only 16 bit data width is available.
・SDATA: It is data input signal.
It is amplitude data. The data length is different according to the resolution of the input digital data.
Data width is selectable as 16 bit, 20 bit or 24 bit.
The digital input has I2S, Left-justified and Right-justified formats.
The figure below shows the timing chart of each transmission mode.
・SDATAO: Audio data after DSP processing.
Data is audio data after DSP processing.
This output is synchronous to LRCK and BCLK.
Output supports only I2S format.
BCLK clock 64fs
16bit Mode
20bit Mode
24bit Mode
LRCLK
BCLK
SDATA
I2S 64fs Format
Left-Justified 64fs Format
Right-Justified 64fs Format
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
Left Channel Right Channel
LRCLK
BCLK
SDATA
16bit Mode
20bit Mode
24bit Mode
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0 MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
Left Channel Right Channel
LRCLK
BCLK
SDATA
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
Left Channel
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
Right Channel
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
Figure 38.
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TSZ22111 • 15 • 001
BCLK clock 48fs
BCLK clock 32fs
16bit Mode
20bit Mode
24bit Mode
LRCLK
BCLK
SDATA
I2S 48fs Format
Left-Justified 48fs Format
Right-Justified 48fs Format
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 1
Left Channel Right Channel
LRCLK
BCLK
SDATA
16bit Mode
20bit Mode
24bit Mode
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0 MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
Left Channel Right Channel
LRCLK
BCLK
SDATA
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
Left Channel
16bit Mode
20bit Mode
24bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
Right Channel
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
16bit Mode
LRCLK
BCLK
SDATA
I2S 32fs Format
Left-Justified 32fs Format
Right-Justified 32fs Format
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
16bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 1
Left Channel Right Channel
LRCLK
BCLK
SDATA
16bit Mode 16bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0 MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Left Channel Right Channel
LRCLK
BCLK
SDATA
16bit Mode 16bit Mode
MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0 MSB LSB
S1413121110 9 8 7 6 5 4 3 2 1 0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Left Channel Right Channel
Figure 39.
Figure 40.
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TSZ22111 • 15 • 001
Format setting for Digital Audio Interface
Please set BCLK clock fs, Data length and Format by transmitting command according to inputted Digital Serial Audio
signal.
SDATAO output data bit width is able to be set independently.
Output supports only I2S format.
BCLK
clock
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x03[ 5:4 ]
0x0
64fs
0x1
48fs
0x2
32fs
0x3
Don't use
Data
format
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x03[ 3:2 ]
0x0
I2S format
0x1
Left-justified format
0x2
Right-justified format
0x3
Don't use
Data
width
Default = 0x2 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x03[ 1:0 ]
0x0
16 bit
0x1
20 bit
0x2
24 bit
0x3
Don't use
SDATAO
output
data
width
Default = 0x2 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x78[ 1:0 ]
0x0
16 bit
0x1
20 bit
0x2
24 bit
0x3
Don't use
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TSZ22111 • 15 • 001
Audio Interface format and timing
Recommended timing and operating conditions (BCLK, LRCLK, SDATA)
No.
Parameter
Symbol
Limit
Unit
Min.
Max.
1
LRCLK frequency
fLRCLK
32
48
kHz
2
BCLK frequency
fBCLK
2.048
3.072
MHz
3
Setup time, LRCLK(Note 1)
tSU;LR
20
－
ns
4
Hold time, LRCLK(Note 1)
tHD;LR
20
－
ns
5
Setup time, SDATA
tSU;SD
20
－
ns
6
Hold time, SDATA
tHD;SD
20
－
ns
7
LRCLK, DUTY
dLRCLK
40
60
%
8
BCLK, DUTY
dBCLK
40
60
%
(Note 1) This regulation is to keep rising edge of LRCK and rising edge of BCLK from overlapping.
Figure 41. Clock timing
Figure 42. Audio Interface timing
LRCLK
BCLK
SDATA
tHD;LR tSU;LR
tHD ;SD
;
tSU ;SD
;
VIH
VIL
VIH
VIL
VIH
VIL
LRCLK
1/fLRCLK
BCLK
1/fBCLK
VIH
VIL
VIH
VIL
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TSZ22111 • 15 • 001
Power supply start-up sequence
*Please make sure to input low to RSTX terminal from external at the time power up DVDD.
*Please refer to [7．The wake-up Procedure of power-up].
Figure 43.
VCCP1
VCCP2
RSTX
BCLK
LRCLK
Speaker
BTL output
(After LC filter)
SDATA
①Power up VCCP1, VCCP2 simultaneously.
②After DVDD rises and 10ms or
more passes, please set RSTX to H.
④Set MUTEX to high.
Soft-start
t
t
t
VCCP1,VCCP2
DVDD
DVDD
SCL
SDA t
⇒Start data transmission
More than 10ms
③After RSTX rises and 1ms or
more passes, please send command.
More than 1ms
t
MUTEX
t
t
OUT1P
OUT1N
OUT2P
OUT2N
Twait *please refer to P.15
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TSZ22111 • 15 • 001
Power supply shut-down sequence
Please don’t stop I2S data before
completion of mute transition
t
t
⑥Power down VCCP1, VCCP2 simultaneously.
VCCP1, VCCP2
Soft mute transition time
VCCP1
VCCP2
Speaker
BTL output
(After LC filter)
DVDD
BCLK
LRCLK
SDATA t
MUTEX
① Set MUTEX＝low
t
t
SCL
SDA t
② After the complition of a mute
transition, set RSTX=low
RSTX
t
OUT1P
OUT1N
OUT2P
OUT2N
PWM stop time
※Please make sure to input low to RSTX terminal when DVDD is powered down.
Figure 44.
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TSZ22111 • 15 • 001
About the protection function
(Note 1) The ERROR pin is Nch open-drain output.
(Note 2) Once an IC is latched, the circuit is not released automatically even after an abnormal status is removed.
The following procedures ① or ② is available for recovery.
①After MUTEX pin is made low once over PWM stop time, MUTEX pin is returned to high again.
②Turning on the power supply again (VCCP1, VCCP2<2.5V, 10ms(min)).
Protection
function
Detecting & Releasing condition
Speaker
PWM output
ERROR(Note 1)
output
Output short
protection
Detecting
condition
Detecting current = 7.2A (TYP.)
HiZ_low
(latch) (Note 2)
Low
(latch)
DC voltage
protection
Detecting
condition
PWM output Duty=0% or 100%
for 12μs(TYP)and over
HiZ_low
(latch) (Note 2)
Low
(latch)
High
temperature
protection
Detecting
condition
Chip temperature to be above 150℃ (TYP.)
HiZ_low
Low
Releasing
condition
Chip temperature to be below 120℃ (TYP.)
Normal
operation
Under voltage
protection
Detecting
condition
Power supply voltage to be below 7.0V (TYP.)
HiZ_low
High
Releasing
condition
Power supply voltage to be above 7.5V (TYP.)
Normal
operation
Clock stop
protection
Detecting
condition
BCLK signal have stopped among constant period.
LRCLK signal have stopped among constant period.
BCLK frequency is under constant value.
BCLK frequency is over constant value.
Please refer to P.55-58 about constant value.
HiZ_low
High
Releasing
condition
LRCLK signal haven’t stopped among constant
period and BCLK continues maximum 60ms or more
of continuous appropriate frequency.
Please refer to P.55-58 about constant value.
Normal
operation
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TSZ22111 • 15 • 001
1) Output short protection (Short to the power supply)
This IC has the output short protection circuit that stops the PWM output when the PWM output is short-circuited to the
power supply due to abnormality.
Detecting condition - It will detect when MUTEX pin is set high and the current that flows in the PWM output pin
becomes 7.2A(TYP.) or more. The PWM output instantaneously enters the state of HiZ-low if
detected, and IC does the latch.
Releasing method - ①After MUTEX pin is set low once over the PWM stop time(see page 15), MUTEX
pin is returned to high again.
②Turning on the power supply again (VCCP1, VCCP2<2.5V, 10ms(min)).
2) Output short protection (Short to GND)
This IC has the output short protection circuit that stops the PWM output when the PWM output is short-circuited to GND
due to abnormality.
Detecting condition - It will detect when MUTEX pin is set high and the current that flows in the PWM output terminal
becomes 7.2A(TYP.) or more. The PWM output instantaneously enters the state of HiZ-low if
detected, and IC does the latch.
Releasing method – ①After MUTEX pin is set low once over the PWM stop time(see page 15), MUTEX pin is returned
to high again.
②Turning on the power supply again (VCCP1, VCCP2<2.5V, 10ms(min)).
Short to VCC Release from short to VCC
PWM out： IC latches with HiZ-low. Normal operation after released
from latch state.
１μs(TYP.)
t
t
t
7.2A(TYP.)
Over current
t
Latch release
PWM stop
time
ERROR (13pin)
MUTEX（30pin）
OUT1P (25pin)
OUT1N (21pin)
OUT2P (20pin)
OUT2N (16pin)
Short to GND Release from short to GND
PWM out ：IC latches with HiZ-low state. Normal operation after released
from latch state.
１μs(TYP.)
t
t
t
7.2A(TYP.)
t
Latch release
ERROR (13pin)
MUTEX（30pin）
Over current
PWM stop time
OUT1P (25pin)
OUT1N (21pin)
OUT2P (20pin)
OUT2N (16pin)
Figure 45.
Figure 46.
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TSZ22111 • 15 • 001
3) DC voltage protection in the speaker
When the DC voltage in the speaker is impressed due to abnormality, this IC has the protection circuit where the speaker
is defended from destruction.
Detecting condition - It will detect when MUTEX pin is set high and PWM output Duty=0% or 100% over
12μs.(fs=48kHz) Once detected, The PWM output instantaneously enters the state of HiZ-low, and
IC does the latch.
Releasing method – ①After MUTEX pin is set low once over the PWM stop time(see page 15), MUTEX pin is returned
to high again.
②Turning on the power supply again (VCCP1, VCCP2<2.5V, 10ms(min)).
Speaker out
Latch release state.
ERROR (13pin)
t
t
t
t
MUTEX(30pin)
Latch release
Abnormal state release
Soft -start
PWM out : IC latches with HiZ - low state
Protection start surge current
into speaker output
for 12µs and over.
PWM out locked duty=100% abnormal state.
PWM stop time
OUT1P (25pin)
OUT1N (21pin)
OUT2P (20pin)
OUT2N (16pin)
Figure 47.
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TSZ22111 • 15 • 001
4) High temperature protection
This IC has the high temperature protection circuit that prevents thermal reckless driving under an abnormal state for the
temperature of the chip to exceed Tjmax=150℃.
Detecting condition - It will detect when MUTEX pin is set high and the temperature of the chip becomes 150℃(TYP.)
or more. The speaker output is muted when detected.
Releasing condition - It will release when MUTEX pin is set high and the temperature of the chip becomes 120℃(TYP.)
or less. The speaker output is outputted when released.
OUT1P (25pin)
150℃
120℃
3.3V
ERROR (13pin)
OUT1N (21pin)
OUT2N (16pin)
OUT2P (20pin)
t
t
t
t
Speaker
BTL output
(After LC filter)
HiZ-low
Temparature of
IC chip junction (℃)
Figure 48.
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Speaker
BTL output
(After LC filter)
ERROR (13pin)
3.3V
VCCP1 (24pin)
VCCP2 (17pin)
t
t
t
t
HiZ- low
7.0V
7.5V
OUT1P (25pin)
OUT1N (21pin)
OUT2P (20pin)
OUT2N (16pin)
5) Under voltage protection
This IC has the under voltage protection circuit that make speaker output mute once detecting extreme drop of the power
supply voltage.
Detecting condition – It will detect when MUTEX pin is set high and the power supply voltage becomes lower than 7.0V.
The speaker output is muted when detected.
Releasing condition – It will release when MUTEX pin is set high and the power supply voltage becomes more than
7.5V. The speaker output is outputted when released.
Figure 49.
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6) Clock stop protection
This IC has the clock stop protection circuits that make the speaker output mute when the BCLK and LRCLK frequency
of the digital sound input are decreased or low frequency.
Detecting condition - BCLK frequency is low or stop, LRCLK frequency is stop. Speaker output is muted.
Releasing condition - Mute is released when it passes more than 60ms after an internal error state was removed.
(max).
BCLK
LRCLK
Speaker
BTL output
(After LC filter)
Soft-start
t
t
t
OUT1P
OUT1N
OUT2P
OUT2N
Internal
Error
flag
Low frequency or stop
Normal input
Max 60m
Max 60ms
Figure 50.
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Functional descriptions of DSP Block
1．Digital Sound Processing(DSP)
The digital sound processing (DSP) part of BM28720 is composed of the special hardware which is the optimal for FPD-TV,
the Mini/Micro Compo. BM28720MUV does the following processing using this special DSP.
Pre-Scaler, Channel Mixer, 12 Band BQ, Fine Master Volume, 3 Band DRC, Fine Post-Scaler,
DC Cut HPF, Hard Clipper
The
outline
and
signal
flow
of
the
DSP
part
Data width: 32 bit (DATA RAM)
Machine cycle: 20.3ns (1024fs, fs=48kHz)
Multiplier: 32×24 → 56 bit
Adder: 56＋56 → 56 bit
Data RAM: 512×32 bit
Coefficient RAM: 512×24 bit
Sampling frequency : fs=32k,44.1k,48kHz
The digital signal from 16 bits to 24 bits is inputted to the DSP but extends 8bit(+48dB) as the overflow margin to the upper
side. When doing the processing which exceeds this range, it processes a clip in the DSP. Incidentally, in case of the 2nd
IIR-type (BQ) filter which is often used generally as the digital filter, because it consumes a lot of overflow margins, the
output of the multiplier and the adder inside needs note.
Z-1
Z-1
b0
b1
b2
Z-1
Z-1
a1
a2
Direct form 1
X[n]
X[n-1]
X[n-2]
Y[n]
Y[n-1]
Y[n-2]
The output of multipliers and the adding machine might exceed
+48dB by the coefficient of a1, a2, b0, b1, and b2. In that case,
data becomes saturation power. Therefore, the output of the filter
cannot obtain the aimed characteristic.
-1 is multiplied by the coefficient of a1 and a2.
Input1 Main
Pre
Scaler
Fine
Master
Volum
e/ch
Fine
Post
Scaler/
ch
DC Cut
HPF Hard
Clipper
I2S
LJ
RJ
3Band
DRC
Chanel
Mixer Post
Scaler
12Band
/ch BQ
データ
RAM
MUX
M
U
X
係数
RAM
デコーダ
回路
MUX
ADD
Acc
入力
0
出力
係数演算
回路
Figure 51.
Figure 52.
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The management of audio data is as follows by each block.
1-1. Bypass
It enable pass the some function of the DSP. By using it, it left the set value of the each function and can be passed that
function. it is possible to make ON/OFF of the sound effect easily.
1) 12 Band BQ, 2) 3 Band DRC and the 3) whole DSP can be passed.
Input1 Main
Fine
Master
Volume
/ch
Chanel
Mixer
I2S
LJ
RJ
Pre
Scaler
12Band
/ch BQ
3Band
DRC
Post
Scaler
Fine
Post
Scaler/
ch
DC Cut
HPF
Hard
Clipper
SW1 SW2 SW3
Default = 0x00 *Blue square means initial value.
Select Address
bit
Explanation of operation
0x02 [2:0]
2
Bypass of 12 Band BQ (SW1) 0:Normal 1:Bypass
1
Bypass of 3 Band DRC (SW2) 0:Normal 1:Bypass
0
Bypass of DSP (SW3) 0:Normal 1:Bypass
Audio DATA
Data of DSP part
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
S Extension bit DATA[22:0]
Decimal point
23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
SEXT. bit Coefficient data[20:0] Coefficient data
Decimal point
Coefficient data of DSP part
Figure 53.
Figure 54.
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1-2. Pre-Scaler
Pre-Scaler adjusts gain of input audio data. The adjustable-range can be set from +48 dB to -79 dB with the 0.5-dB step.
(Lch/Rch use same value)
Pre-Scaler doesn't have a soft transfer feature.
Default = 0x60 *Blue square means initial value.
Select Address
Explanation of operation
0x16 [ 7:0 ]
1-3. Channel setup
with
a
phase
inversion
function
(
(Channel
Mixer
1)
)
It sets a mixing in the sound on the left channel and the right channel of the digital signal which was inputted to the DSP.
It makes a stereo signal a monaural here. Also, the phase-inversion, the mute on each channel can be set.
0x01 +47.5dB
……
……
0dB
-0.5dB
Command Value Gain
0x00
0x62
0xFE
0xFF
+48dB
-1dB
-79dB
-∞
0x60
0x61
Input
I2S
LJ
RJ
Pre-
Scaler
L
R
1/2
L
(L+R)/2±1
±1
Lch
Rch
Channel Mixer
Mute
R
0
L-R
-
Figure 55.
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DSP input: The data inputted into Lch of DSP is inverted.
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x17[7]
0x0
Normal
0x1
Invert
DSP input: The data inputted into Lch of DSP is mixed.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x17 [ 6:4 ]
0x0
Mute
0x1
Lch data input
0x2
Rch data input
0x3
(Lch + Rch) / 2
0x4
Lch-Rch
DSP input: The data inputted into Rch of DSP is inverted.
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x17 [3]
0x0
Normal
0x1
Invert
DSP input: The data inputted into Rch of DSP is mixed.
Default = 0x2 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x17 [ 2:0 ]
0x0
Mute
0x1
Lch data input
0x2
Rch data input
0x3
(Lch + Rch) / 2
0x4
Lch-Rch
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1-4. Biquad filter
In this IC, the following block has the biquad type filter(BQ).
There are 12 Band BQ, Crossover filter of 3 Band DRC block and BQ of the smooth transition.
The shape is used as peaking filter, low shelf filter, high shelf filter, low-pass filter, high-pass filter, notch filter and all path
filters.
Setting the coefficient of the digital filter in the IC by transmit to the coefficient RAM via command. 12 Band BQ have the
soft transfer feature. About the detailed order of the parameter setting, please refers to the following BQ setting method.
Select of BQ independence or synchronous setting
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x60 [ 4 ]*
0x0
L/R common setting
0x1
L/R independence setting
*0x60[4] setting note.
Please re-set all BQ when you change the setting of 0x60[4].
Total 18 BQ needs to be set again. (BQ1-12, DRC1, DRC2 and DRC3).
BQ soft transition destination band
Default = 0x0 *Blue square means initial value.
Select Address
Explanation of operation
0x51 [ 4:0 ]*
Select of smooth transition
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x53 [ 6 ]
0x0
Use smooth transition
0x1
Not use smooth transition
0x00 12BAND(1)
12BAND(3)
12BAND(5)
Value Destination
0x01 12BAND(2)
0x02
0x03
0x08
0x09
12BAND(12)
12BAND(11)
12BAND(10)
12BAND(9)
12BAND(8)
12BAND(7)
12BAND(6)
12BAND(4)
Value Destination
0x04
0x05
0x06
0x07
0x0A
0x0B
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Select the destination channel of smooth transition
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x53 [ 5:4 ]
0x0
Lch とRch
0x1
Lch
0x2
Rch
0x3
Don't use
Setting of smooth transition time
Default = 0x3 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x53 [ 3:2 ]
0x0
2.7ms
0x1
5.3ms
0x2
10.7ms
0x3
21.3ms
Setting of smooth transition wait time
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x53 [ 1:0 ]
0x0
2.7ms
0x1
5.3ms
0x2
10.7ms
0x3
21.3ms
Setting of smooth transition start
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x58 [ 0 ]
0x0
Stop the smooth transition operation
0x1
Start the smooth transition operation (After the transition is completed,
it becomes 0 automatically)
This register is write only.
Read-out smooth transition status
Read only
Select Address
Explanation of operation
0x59 [ 0 ]
1 : Executing soft transition
0 : Not during soft transition
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1-5. Volume
Volume is from+24dB to -103dB, and can be selected by the step of 0.125dB. And it is possible to be setting of -∞dB, too.
At the time of switching of Volume, smooth transition is performed. Soft transition duration is optional with the command.
L/R synchronous or L/R independent can be selected by 0x10[7].
It becomes the following formula at the transition from AdB to BdB. C is smooth transition duration selected by 0x15[7:6]
command.
| (10
A
20 ) * C ms |
10
B
20
-
Transition time =
Setting of soft transition time
Default = 0x0 *Blue square means initial value.
Select Address
Value
動作説明
0x15 [ 7:6 ]
0x0
21.3ms
0x1
42.7ms
0x2
85.3ms
0x3
Don't use
Lch/common volume setting
Default = 0xFF *Blue square means initial value.
Select Address
Explanation of operation
0x11 [ 7:0 ]
0x01 +23.5dB
……
……
0dB
-0.5dB
Value Gain
0x00
0x32
0xFE
0xFF
+24dB
-1dB
-103dB
-∞
0x30
0x31
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Setting of fine volume
This command becomes effective by sending the following command after setting.
When using this command, it is possible to set a volume in 0.125dB carving.
When L/R synchronous volume setting, 0x11[7:0] is enable.
When L/R independent volume setting, 0x11[7:0] is the volume setting of Lch.
Lch/common fine volume setting
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x10 [ 1:0 ]
0x0
0dB
0x1
-0.125dB
0x2
-0.25dB
0x3
-0.375dB
【Note1】
It is possible to use with the 0.5-dB step in changing only 0x11[7:0] when 0x10[1:0]=0x0.
The Lch/Rch independent volume setting and the synchronous volume setting can be selected by 0x10[7] command.
When Lch/Rch independent volume set, the volume setting of Lch is the setting of 0x10[1:0] and 0x11, and the volume
setting of Rch is the settings of 0x10[5:4] and 0x12.
Setting of Lch/Rch independent volume
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x10[ 7 ]
0x0
Lch/Rch common volume setting
0x1
Lch/Rch independent volume setting
Setting of volume (Setting of Rch volume, It is enable only to set an independent volume.)
Default = 0xFF *Blue square means initial value.
Select Address
Explanation of operation
0x12 [ 7:0 ]
Setting of fine volume
This command becomes effective by sending the following command after setting.
When using this command, it is possible to set a volume in 0.125dB carving.
Setting of fine volume (Setting of Rch fine volume, It is enable only to set an independent volume.)
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x10 [ 5:4 ]
0x0
0dB
0x1
-0.125dB
0x2
-0.25dB
0x3
-0.375dB
【Note2】
It is possible to use with the 0.5-dB step in changing only 0x12[7:0] when 0x10[5:4]=0.
0x01 +23.5dB
……
……
0dB
-0.5dB
Value Gain
0x00
0x32
0xFE
0xFF
+24dB
-1dB
-103dB
-∞
0x30
0x31
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【Note3】
It is possible to use with the 0.125-dB step in setting both 0x10[1:0] and 0x11[7:0].
In case of 0x10[1:0] = 0x0, it becomes the set value of 0x11[7:0].
In case of 0x10[1:0] = 0x1, it becomes the -0.125dB set value of 0x11[7:0].
In case of 0x10[1:0] = 0x2, it becomes the -0.25dB set value of 0x11[7:0].
In case of 0x10[1:0] = 0x3, it becomes the -0.375dB set value of 0x11[7:0].
Because it is fixed by the transfer of 0x11 in any case, the soft transfer can be beforehand begun in the set value for the
direct following of the purpose in setting 0x11 after setting in 0x10.
0x10[5:4] is the same function as 0x10[1:0 ], 0x12 is the same function as 0x11 when Lch/Rch independently set for Rch.
1-6. 3 band DRC
This DRC is used in order to prevent clip output of a large audio signal.
There are three kinds of DRC (DRC1, DRC2, and DRC3), and non clip output can be achieved at each band.
DRC1, DRC2 and DRC3 can set up two threshold value levels. Moreover, it is possible to also change slope.
0x11 0x11
Volume
When use 0.5dB steps
0x10→0x11
Volume
When use 0.125dB steps
0x10→0x11
Input
APF
Output
3 Band DRC block diagram
HPF DRC3
DRC1
Crossover
Filters AGC_TH1, Slope α
AGC_TH1, Slope α
LPF
DRC2
AGC_TH1, Slope α
DRC4
Figure 56.
Figure 57.
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DRC transition figure
In here A_TIME is the time for detecting time before starting gain down operation. And A_RATE decides the slope of gain
compression.
On the other hand R_TIME is the time for detecting before starting to release gain operation. And R_RATE decides slope of
release gain.
DRC1, DRC2, DRC3 can be set AGC_TH1 and AGC_TH2 as shown in below. If output is in between AGC_TH1 and
AGC_TH2, a slant for output gain can be made. If input become bigger and output over AGC_TH2, output gain don't have
slant and become constant level. Value for slant setting (α) is calculated by AGC_TH1, AGC_TH2 and the value of input gain
for reaching AGC_TH2 (xdB).
The operation between AGC_TH1 and AGC_TH2 is decided as DRC1slope and DRC2slope and DRC3slope.
And the operation over AGC_TH2 is decided as DRC1comp and DRC2comp and DRC3comp.
Each operation can be set ON/OFF, A_TIME, A_RATE, R_TIME, R_RATE respectively.
DRC input-and-output gain characteristics
A_TIME
AGC_TH
AGC_TH
R_TIME
R_ RATEA_ RATE
Input
Output
Volume
Level
R_TIME
A_TIME
VI
[dB]
VO
VIinf
VOinf
α
AGC_TH1
-12dB
The formula which asks for Slope alpha is described below.
Alpha changes into 8bit Hex data of the complement of 2 the value calculated by calculation.
AGC_TH2
y = -6dB
x = 0dB
TH is AGC_TH1. x is input level. y is output level.
Ex) It asks for alpha at the time of AGC_TH1 = -12dB, x = 0dB y = -6dB
α= 10
y
20 10
x
20
-
10
TH
20 10
x
20
-
× 128
α= 10
-6
20 10
0
20
-
10
-12
20 10
0
20
-
× 128
α= 85.266 →0x55
0x55 calculated is set as 0x29, 0x31 or 0x39.
α= 0x00
α= 0x80
-12dB
Figure 58.
Figure 59.
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Volume Curve
DRC1slope ON/OFF setting
OFF is through output.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x20 [ 7]
0x0
Not use
0x1
Use
DRC1comp ON/OFF setting
OFF is through output.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x20 [ 6 ]
0x0
Not use
0x1
Use
DRC2slope ON/OFF setting
OFF is through output.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x20 [ 5 ]
0x0
Not use
0x1
Use
DRC2comp ON/OFF setting
OFF is through output.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x20 [ 4 ]
0x0
Not use
0x1
Use
Time
Volume
Level
AGC_TH A_RATE R_RATE
Exponential
Curve
Linear
Curve Linear
Curve
Exponential
Curve
Figure 60.
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DRC3slope ON/OFF setting
OFF is through output.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x20 [ 3 ]
0x0
Not use
0x1
Use
DRC3comp ON/OFF setting of compressor
OFF is through output.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x20 [ 2 ]
0x0
Not use
0x1
Use
DRC4 ON/OFF setting
DRC4 have only compression function. DRC4 don't have slope function.
OFF is through output.
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x3F [ 4 ]
0x0
Not use
0x1
Use
The volume curve at the time of an attack (A_RATE) is selected.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x21[ 7 ]
0x0
Linear curve
0x1
Exponential curve
The volume curve at the time of a release (R_RATE) is selected.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x21 [ 6 ]
0x0
Linear curve
0x1
Exponential curve
DRC is 1 Band setting at initial state.
To set the crossover filter (HPF, LPF and APF) which divides the frequency band of 3 Band DRC, therefore, it is referred to
the 1-4.
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Slope (α) setting of DRC1slope, DRC2slope, and DRC3slope
DRC1slope, DRC2slope and DRC3slope can be set individually.
Default = 0x80 *Blue square means initial value.
Select Address
Explanation of operation
DRC1slope 0x29 [ 7:0 ]
DRC2slope 0x31 [ 7:0 ]
DRC3slope 0x39 [ 7:0 ]
AGC_TH1 setting of DRC1slope, DRC2slope, and DRC3slope
DRC1slope, DRC2slope and DRC3slope can be set individually.
Please set this value is smaller than the value of AGC_TH2.
Default = 0x40 *Blue square means initial value.
Select Address
Explanation of operation
DRC1slope 0x28 [ 6:0 ]
DRC2slope 0x30 [ 6:0 ]
DRC3slope 0x38 [ 6:0 ]
AGC_TH2 setting of DRC1comp, DRC2comp, DRC3comp, and DRC4
DRC1comp, DRC2comp, DRC3comp and DRC4 can be set individually.
Default = 0x40 *Blue square means initial value.
Select Address
Explanation of operation
DRC1comp 0x2C [ 6:0 ]
DRC2comp 0x34 [ 6:0 ]
DRC3comp 0x3C [ 6:0 ]
DRC4 0x40 [ 6:0 ]
VI
[dB]
VO
VIinf
VOinf
α
AGC_TH1
-12dB
The formula which asks for Slope alpha is described below.
Alpha changes into 8bit Hex data of the complement of 2 the value calculated by calculation.
AGC_TH2
y = -6dB
x = 0dB
TH is AGC_TH1. x is input level. y is output level.
Ex) It asks for alpha at the time of AGC_TH1 = -12dB, x = 0dB y = -6dB
α= 10
y
20 10
x
20
-
10
TH
20 10
x
20
-
× 128
α= 10
-6
20 10
0
20
-
10
-12
20 10
0
20
-
× 128
α= 85.266 →0x55
0x55 calculated is set as 0x29, 0x31 or 0x39.
α= 0x00
α= 0x80
-12dB
-32dB0x00
0dB
+0.5dB
Value Threshold
… …
0x40
0x41
-0.5dB
……
+12dB0x58
0x3F
-32dB0x00
0dB
+0.5dB
Value Threshold
… …
0x40
0x41
-0.5dB
……
+12dB0x58
0x3F
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BM28720MUV
TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
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TSZ22111 • 15 • 001
A_RATE setting of DRC1slope, DRC2slope, DRC3slope, DRC1comp, DRC2comp, DRC3comp, DRC4
DRC1slope, DRC2slope, DRC3slope, DRC1comp, DRC2comp, DRC3comp, DRC4 can be set individually.
Default = 0x3 *Blue square means initial value.
Select Address
Explanation of operation
DRC1slope 0x2A [ 6:4 ]
DRC2slope 0x32 [ 6:4 ]
DRC3slope 0x3A [ 6:4 ]
DRC1comp 0x2E [ 6:4 ]
DRC2comp 0x36 [ 6:4 ]
DRC3comp 0x3D [ 6:4 ]
DRC4 0x41 [ 6:4 ]
R_RATE setting of DRC1slope, DRC2slope, DRC3slope, DRC1comp, DRC2comp, DRC3comp, DRC4
DRC1slope, DRC2slope, DRC3slope, DRC1comp, DRC2comp, DRC3comp, DRC4 can be set individually.
Default = 0xB *Blue square means initial value.
Select Address
Explanation of operation
DRC1slope 0x2A [ 3:0 ]
DRC2slope 0x32 [ 3:0 ]
DRC3slope 0x3A [ 3:0 ]
DRC1comp 0x2E [ 3:0 ]
DRC2comp 0x36 [ 3:0 ]
DRC3comp 0x3D [ 3:0 ]
DRC4 0x41 [ 3:0 ]
A_TIME setting of DRC1slope, DRC2slope, DRC3slope, DRC1comp, DRC2comp, DRC3comp, DRC4
DRC1slope, DRC2slope, DRC3slope, DRC1comp, DRC2comp, DRC3comp, DRC4 can be set individually.
Default = 0x1 *Blue square means initial value.
Select Address
Explanation of operation
DRC1slope 0x2B [ 7:4 ]
DRC2slope 0x33 [ 7:4 ]
DRC3slope 0x3B [ 7:4 ]
DRC1comp 0x2F [ 7:4 ]
DRC2comp 0x37 [ 7:4 ]
DRC3comp 0x3E [ 7:4 ]
DRC4 0x42 [ 7:4 ]
0x0 0.125s
0.25s
0.5s
Value R_RATE
0x1
0x4
0x5
0x6
0x7
0.1825s
0.75s
1s
1.25s
1.5s
0x2
0x3 3s
4s
Value
0x8
0x9
0xC
0xD
0xE
0xF
2s
2.5s
5s
6s
7s
8s
0xA
0xB
R_RATE
0x0 0ms
1ms
1.5ms
Value A_TIME
0x1
0x4
0x5
0x6
0x7
0.5ms
2ms
3ms
4ms
5ms
0x2
0x3 8ms
9ms
Value
0x8
0x9
0xC
0xD
0xE
0xF
6ms
7ms
10ms
20ms
30ms
40ms
0xA
0xB
A_TIME
0x0 1ms
3ms
4ms
Value A_RATE
0x1 2ms
0x2
0x3 20ms
40ms
Value
0x4
0x5 5ms
10ms
0x6
0x7
A_RATE
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TSZ02201-0C1C0E900060-1-2
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TSZ22111 • 15 • 001
R_TIME setting of DRC1, DRC2, DRC3, and DRC4
DRC1, DRC2, DRC3 and DRC4 are individually setting.
Default = 0x3 *Blue square means initial value.
Select Address
Explanation of operation
DRC1slope 0x2B [ 2:0 ]
DRC2slope 0x33 [ 2:0 ]
DRC3slope 0x3B [ 2:0 ]
DRC1comp 0x2F [ 2:0 ]
DRC2comp 0x37 [ 2:0 ]
DRC3comp 0x3E [ 2:0 ]
DRC4 0x42 [ 2:0 ]
0x0 5ms
25ms
50ms
Value R_TIME
0x1 10ms
0x2
0x3 300ms
400ms
Value
0x4
0x5 100ms
200ms
0x6
0x7
R_TIME
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TSZ22111 • 15 • 001
1-7. Post-Scaler
Post-Scaler adjusts gain of output audio data. The adjustable-range can be set from +48 dB to -79 dB with the 0.5-dB step.
(Lch/Rch use same value)
Pre-Scaler doesn't have a soft transfer feature.
Default = 0x60 *Blue square means initial value.
Select Address
Explanation of operation
0x13 [ 7:0 ]
1-8. Fine Post-Scaler
An adjustable range can be set up at a 0.1dB step from +0.7dB to –0.8dB. Fine Post-Scaler does not have a smooth
transition function.
(Lch and Rch can be set different value.)
Default= 0x8 *Blue square means initial value.
Select Address
Explanation of operation
Lch 0x14 [ 7:4 ]
Rch 0x14 [ 3:0 ]
Command
Gain
Command
Gain
0x0
-0.8dB
0x8
0dB
0x1
-0.7dB
0x9
+0.1dB
0x2
-0.6dB
0xA
+0.2dB
0x3
-0.5dB
0xB
+0.3dB
0x4
-0.4dB
0xC
+0.4dB
0x5
-0.3dB
0xD
+0.5dB
0x6
-0.2dB
0xE
+0.6dB
0x7
-0.1dB
0xF
+0.7dB
0x01 +47.5dB
……
……
0dB
-0.5dB
Value Gain
0x00
0x62
0xFE
0xFF
+48dB
-1dB
-79dB
-∞
0x60
0x61
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TSZ02201-0C1C0E900060-1-2
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TSZ22111 • 15 • 001
1-9. Hard Clipper
Measuring output of the television, output power is measured in 10% THD+N condition. It can be made to clip with any
output amplitude by using a clipper function. For example, the output of 10W or 5W can be gained using the amplifier of
15W output.
0dB
-3dB
-6dB
+3dB
Clip level：0dB Clip level：-3dB Clip level：+3dB
0dB
-3dB
-6dB
+3dB
0dB
-3dB
-6dB
+3dB
Hard clip
Clipper setting
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x1A [ 0 ]
0x0
Clipper function is not used.
0x1
Hard clipper function is used.
Clip level selection
Default = 0xE1 *Blue square means initial value.
Select Address
Explanation of operation
0x1B [ 7:0 ]
Figure 61.
…
…
0x00 -22.5dB
0dB
+0.1dB
Value Gain
0xE1
0xE2
-0.1dB
…
…
+3dB0xFF
0xE0
+2.9dB0xFE
0x01 -22.4dB
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TSZ02201-0C1C0E900060-1-2
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TSZ22111 • 15 • 001
1-10. DC Cut HPF
DC offset element of the digital signal outputted from audio DSP is cut by this HPF.
The cutoff frequency fc of HPF uses the 1Hz filter, and the degree uses the first-order filter.
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x18 [ 0 ]
0x0
Not use
0x1
Use
1-11. RAM clear
The data RAM of DSP and coefficient RAM are cleared.
40μs or more is required until all the data is cleared.
Clear of the data RAM
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x01 [ 7 ]
0x0
Normal
0x1
Clear
Clear of coefficient RAM
Default = 0x1 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x01 [ 6 ]
0x0
Normal
0x1
Clear
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TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
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TSZ22111 • 15 • 001
1-12. Audio Output Level Meter
It is possible to output the peak level of the PCM data inputted into a PWM processor.
A peak value can be read using the 2-wire command interface as 16 bit data of an absolute value.
The interval holding a peak value can be selected from six steps (50ms step) from 50ms to 300ms.
A peak hold result can be selected from L channel, R channel, and a monophonic channel {(Lch+Rch) /2}.
Audio Output Level Meter block diagram
Setting of the peak level hold time interval of Audio Output Level Meter
Default = 0x0 *Blue square means initial value.
Select Address
Explanation of operation
0x74 [ 2:0 ]
Figure 62.
Selector
Level Output Register
DSP I2s
0x76, 0x77
0x75 METER_LOAD [1:0]
OUT_LEVEL [15:0]
Peak Hold
(Lch)
Peak Hold
(Rch)
0.5
0x050ms
150ms
200ms
Value Hold time
0x1100ms
0x2
0x3250ms
300ms
0x4
0x5
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TSZ02201-0C1C0E900060-1-2
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TSZ22111 • 15 • 001
The signal of Audio Level Meter read-back is selected.
A value will be taken into a read-only register if a setting value is written in.
In order to update this register value, it is necessary to write in a setting value again.
Write only
Select Address
Value
Explanation of operation
0x75 [ 1:0 ]
0x0
The peak level of L channel
0x1
The peak level of R channel
0x2
The peak level of monophonic channel {(Lch+Rch) /2}
Read-back of Audio Output Level
0x76 (upper 8 bits) and a 0x77 (lower 8 bits) commands are read for the maximum within the period appointed by the
command 0x74 using the 2-wire interface.
(Example)
When 0xFFFF is read, mean 1.0 (0dBFs).
When 0x8000 is read, mean 0.5 (-6dBFs).
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TSZ22111 • 15 • 001
2．Setting and reading method of BQ
It explains a detailed sequence of the setting method and the reading method of the parametric equalizer separately for
usage.
2-1 BQ coefficient setting
The parametric equalizer consists of biquad filter as follows. Each coefficient of biquad filter can be written directly. It is
S2.21 format, and setting range is -4≦x＜+4.
Moreover, the coefficient address is shown in Table 1.
2-1-1 Writing sequence (It sets up in number order)
1. Address setting (0x61) (*1)Table 1 is referred to.
2. 24bit coefficient upper [23:16] bit setting (0x62[7:0])
3. 24bit coefficient middle [15:8] bit setting (0x63[7:0])
4. 24bit coefficient lower [7:0] bit setting (0x64[7:0])
5. The writing of coefficients is performed. (0x65[0] = 0x1) *
* After completion of writing coefficients this register is cleared automatically. It is not necessary to transmit 0x65[0] = 0x0.
Coefficient writing takes about 100μs.100μs should not change an address setup and several 24-bit setup after coefficient
write-in execution.
(ex) When 0x3DEDE7 is written, same L/Rch, 12band BQ1 b0
1. 0x61 = 0x00 (12band BQ1 b0 is appointed)
2. 0x62 = 0x3D (Upper [23:16] is setting)
3. 0x63 = 0xED (Middle [15:8] is setting)
4. 0x64 = 0xE7 (Lower [7:0] is setting)
5. 0x65 = 0x01 (Coefficient transfer)*
*After completion of writing coefficients this register is cleared automatically.
6. 100μs or more wait
2-1-2 Read-back sequence (It sets up in number order)
1. Address setting (0x61) . Please refer to Table 1.
2. Setting of a read-back register address (0xD0)
3. Read-back of the 24bit coefficient upper[23:16]bit (0x66[7:0])
4. Read-back of the 24bit coefficient middle[15:8]bit (0x67[7:0])
5. Read-back of the 24bit coefficient lower[7:0]bit (0x68[7:0])
2-1-3 When the coefficient of PEQ is set up directly and a soft transition is performed
1. Set PEQ coefficient to soft transition address whose address is 0x50-0x54. Please refer to Table1.
Since in the case of 0x60[4] = 0x1(Enable L/R independent setting) and 0x53 [5:4] = 0x0 a soft transition is carried out
and it is set to LR simultaneously, please write a coefficient in both LR address.
In the case of 0x53[5:4] = 0x1, coefficient is set to only Lch address.
In the case of 0x53[5:4] = 0x2, coefficient is set to only Rch address.
2. Select PEQ Band that is performed soft transition by setting 0x51[4:0] address.(Refer to chapter 1-4)
3. 0x58[0] = 0x1：Start soft transition (After the completion of soft transition this register is automatically cleared.)
4. Wait soft transition completion (It depend on soft transition time setting), or read command 0x59 [0], and stand by until it
is cleared.
Figure 63.
Z-1
Z-1
b0
b1
b2
Z-1
Z-1
a1
a2
Direct form 1
X[n]
X[n-1]
X[n-2]
Y[n]
Y[n-1]
Y[n-2]
The output of multipliers and the adding machine might exceed
+48dB by the coefficient of a1, a2, b0, b1, and b2. In that case,
data becomes saturation power. Therefore, the output of the filter
cannot obtain the aimed characteristic.
-1 is multiplied by the coefficient of a1 and a2.
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TSZ22111 • 15 • 001
Table1. Specified coefficient
0x61[6:0]
Destination
0x61[6:0]
Destination
0x61[6:0]
Destination
0x00
12BandBQ1 b0
0x23
12BandBQ8 b0
0x46
DRC2_1 b0
0x01
12BandBQ1 b1
0x24
12BandBQ8 b1
0x47
DRC2_1 b1
0x02
12BandBQ1 b2
0x25
12BandBQ8 b2
0x48
DRC2_1 b2
0x03
12BandBQ1 a1
0x26
12BandBQ8 a1
0x49
DRC2_1 a1
0x04
12BandBQ1 a2
0x27
12BandBQ8 a2
0x4A
DRC2_1 a2
0x05
12BandBQ2 b0
0x28
12BandBQ9 b0
0x4B
DRC2_2 b0
0x06
12BandBQ2 b1
0x29
12BandBQ9 b1
0x4C
DRC2_2 b1
0x07
12BandBQ2 b2
0x2A
12BandBQ9 b2
0x4D
DRC2_2 b2
0x08
12BandBQ2 a1
0x2B
12BandBQ9 a1
0x4E
DRC2_2 a1
0x09
12BandBQ2 a2
0x2C
12BandBQ9 a2
0x4F
DRC2_2 a2
0x0A
12BandBQ3 b0
0x2D
12BandBQ10 b0
0x50
Smooth BQ b0
0x0B
12BandBQ3 b1
0x2E
12BandBQ10 b1
0x51
Smooth BQ b1
0x0C
12BandBQ3 b2
0x2F
12BandBQ10 b2
0x52
Smooth BQ b2
0x0D
12BandBQ3 a1
0x30
12BandBQ10 a1
0x53
Smooth BQ a1
0x0E
12BandBQ3 a2
0x31
12BandBQ10 a2
0x54
Smooth BQ a2
0x0F
12BandBQ4 b0
0x32
12BandBQ11 b0
0x55
DRC3_1 b0
0x10
12BandBQ4 b1
0x33
12BandBQ11 b1
0x56
DRC3_1 b1
0x11
12BandBQ4 b2
0x34
12BandBQ11 b2
0x57
DRC3_1 b2
0x12
12BandBQ4 a1
0x35
12BandBQ11 a1
0x58
DRC3_1 a1
0x13
12BandBQ4 a2
0x36
12BandBQ11 a2
0x59
DRC3_1 a2
0x14
12BandBQ5 b0
0x37
12BandBQ12 b0
0x5A
DRC3_2 b0
0x15
12BandBQ5 b1
0x38
12BandBQ12 b1
0x5B
DRC3_2 b1
0x16
12BandBQ5 b2
0x39
12BandBQ12 b2
0x5C
DRC3_2 b2
0x17
12BandBQ5 a1
0x3A
12BandBQ12 a1
0x5D
DRC3_2 a1
0x18
12BandBQ5 a2
0x3B
12BandBQ12 a2
0x5E
DRC3_2 a2
0x19
12BandBQ6 b0
0x3C
DRC1_1 b0
0x1A
12BandBQ6 b1
0x3D
DRC1_1 b1
0x1B
12BandBQ6 b2
0x3E
DRC1_1 b2
0x1C
12BandBQ6 a1
0x3F
DRC1_1 a1
0x1D
12BandBQ6 a2
0x40
DRC1_1 a2
0x1E
12BandBQ7 b0
0x41
DRC1_2 b0
0x1F
12BandBQ7 b1
0x42
DRC1_2 b1
0x20
12BandBQ7 b2
0x43
DRC1_2 b2
0x21
12BandBQ7 a1
0x44
DRC1_2 a1
0x22
12BandBQ7 a2
0x45
DRC1_2 a2
When L/R independent, Lch:0x61[7]=0x0, Rch:0x61[7]=0x1.
When L/R is same, 0x61[7] is not effective.
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TSZ22111 • 15 • 001
3．The mute function by a terminal
BM28720MUV has a mute function of audio DSP by a terminal.
It is possible to perform mute of the output from Audio DSP by setting a MUTEX terminal to low.
Transition time setting at the time of mute is as follows.
Smooth transition mute time setting
The transition time when changing to a mute state is selected.
The soft transition time at the time of mute release is 10.7ms fixed.
Default = 0x3 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x15 [ 1:0 ]
0x0
10.7ms
0x1
21.4ms
0x2
42.7ms
0x3
85.4ms
0x15[1:0] Mute time setting
Audio output data
TATB
0x0 10.7ms
42.7ms
85.4ms
Command TA
0x1 21.4ms
0x2
0x3
10.7ms
10.7ms
10.7ms
0x15[1:0] setting
10.7ms
TB
It is only operated by mute terminal.
XdB Mute state
Figure 64.
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TSZ22111 • 15 • 001
Smooth transition mute release time setting
Time after detecting mute release until it actually begins mute release operation is set up.
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x15 [ 5:4 ]
0x0
0ms
0x1
100ms
0x2
200ms
0x3
300ms
Operation of mute delay 0x15[5:4]
MUTEX
Audio output data
TM300ms
TM
0x3 200ms
100ms0x1
0 0ms
0x2
0x0 0ms
Command
Figure 65.
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TSZ22111 • 15 • 001
4．Small signal input detection function
There is a function which detects the audio data input of a non-signal or a small signal. This function is used in order to
reduce the standby power consumption of an audio set. Setting of a detection level and detection time can be performed.
If the signal below a setting detection level continues in both low channel and R channel, a small signal detection flag will
become "high". A detection result can be read from command 0x72 [0].
The point which acts as a monitor of the small signal becomes input data of audio DSP block.
Block diagram
Detection level setting
Default = 0x00 *Blue square means initial value.
Select Address
Explanation of operation
0x70 [ 4:0 ]
Detection time setting
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x71 [ 1:0 ]
0x0
42.7ms
0x1
85.4ms
0x2
170.7ms
0x3
341.4ms
* Sampling frequency is value of Fs = 48kHz. In the case of Fs = 44.1kHz, it will be about 1.09 times the setting value.
Detection flag read-back
Read Only
Select Address
Value
Explanation of operation
0x72 [ 0 ]
0x0
Undetected
0x1
Detecting
DSP
I2S
Peak Detector
(Lch)
Counter
Flag
0x72 [0] NOSIG_DET_FLAG
Peak Detector
(Rch)
Figure 66.
-70dB0x0F
0x00 -103dB
-91dB
-84dB
Value Level
0x01 -93dB
0x02
0x03
-60dB
Value
0x08
0x09
0x0A
0x0B
Level
-62dB
-64dB
-65dB
-66dB
-67dB
-68dB
-69dB
-71dB
-72dB
-73dB
-74dB
-75dB
-76dB
-77dB
-78dB
-79dB
-80dB
-87dB
Value Level
0x04
0x05
0x06
0x07
0x0C
0x0D
0x0E
0x10
0x11
0x12
0x13
0x14
0x15
0x16
0x17
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TSZ22111 • 15 • 001
5．Clock stop detection and detection of BCLK frequency begin too low or too high or asynchronous state
detection
5-1. Clock stops detection
BM28720MUV needs some clock source for generating proper clock to process Audio data.
By stopping these cock sources, these clocks to process Audio data also stop.
To prevent noise sounds, we need to detect BCLK or LRCLK stop condition.
As we detect stop flag that is to be valid, output is gone to mute state (mute instantly).
Each detect condition is set by below command. We can check detected result by reading back flag register.
These flags are cleared only by sending specified commands.
LRCLK stop detection time
Default = 0x2 *Blue square means initial value.
Select Address
Value
Operation
LRCLK 0x07 [ 2:0 ]
0x0
10μs to 20μs
0x1
20μs to 40μs
0x2
50μs to 100μs
0x3
100μs to 200μs
0x4
200μs to 400μs
0x5
300μs to 600μs
0x6
400μs to 800μs
0x7
500μs to 1000μs
※Detection time has the above-mentioned variation within the limits.
BCLK stop detection time
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
BCLK 0x08 [ 6:4 ]
0x0
10μs to 20μs
0x1
20μs to 40μs
0x2
50μs to 100μs
0x3
100μs to 200μs
0x4
200μs to 400μs
0x5
300μs to 600μs
0x6
400μs to 800μs
0x7
500μs to 1000μs
※Detection time has the above-mentioned variation within the limits.
Internal
frequency
generator
Clock stop
detecion
circuit
BCLK
LRCLK
Judge
OK/NG
Figure 67.
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TSZ22111 • 15 • 001
Stop detection flag read back register
Read Only
Select Address
Value
Operation
0x09 [ 5 ]
0x0
Normal
0x1
Detection of LRCLK stop flag
0x09 [ 4 ]
0x0
Normal
0x1
Detection of BCLK stop flag
Stop detection flag clear register
Write Only
Select Address
Operation
0x09 [ 1 ]
LRCLK stop detection flag is cleared by writing 1.
0x09 [ 0 ]
BCLK stop detection flag is cleared by writing 1.
※When using a clock error auto return function (P.59), this flag is cleared automatically.
LRCLK stop flag valid or invalid selection
Default = 0x1 *Blue square means initial value.
Select Address
Value
Operation
0x07 [ 3 ]
0x0
Valid
0x1
Invalid
BCLK stop flag valid or invalid selection
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
0x08 [ 7 ]
0x0
Valid
0x1
Invalid
5-2. Synchronous blank detection
As for synchronous blank detecting function, it detects as synchronous blank error when it counts between the rising edges
of LRCK with internal clock (49.152MHz), and it shifts more than the definite value, and whether PLL is normally locked is
judged.
Input sampling frequency
32kHz,44.1kHz,48kHz
Count value
(Start of counting from 0)
1023
As for the detection result, reading from the register is possible. Register value is not cleared until a clear command is
transmitted even if the state of the clock returns normally. Moreover, the setting of the detection approval frequency is also
possible, and if the error counts more than the predetermined number is detected, the flag (0x06[1]) becomes 1.
Synchronous blank flag reading register
Read Only
Select Address
Value
Explanation of operation
0x06 [ 1 ]
0x0
Normal
0x1
Detect synchronous error
Synchronous blank flag clear register
Write Only
Select Address
Explanation of operation
0x06 [ 0 ]
When 1 is written, the synchronous blank flag is cleared.
* When using a clock error auto return function (P.59), this flag is cleared automatically.
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BM28720MUV
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www.rohm.com
TSZ22111 • 15 • 001
Synchronous blank count setting
Default = 0x2 *Blue square means initial value.
Select Address
Explanation of operation
0x06 [ 6:4 ]
Please set more than 1.
5-3. BCLK high or low speed detection
BCLK high or low speed detection function is to judge BCLK speed being too high or low by measuring by using internal
clock (12MHz to 25MHz).
When using BCLK speed detection, speed failure detection can be more correctly performed by setting a command
according to inputted sample rate.
When you use error detection function, please set up the sample rate by setting address 0x0C[1:0]. A high speed and the
low-speed detection flag can be set up valid or invalid respectively, and if the error is detected, mute (mute instantly) will be
carried out.
Valid or invalid frequency value setting up by 0x0C[1:0] command.
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
0x0A [ 3 ]
0x0
Valid
0x1
Invalid
Setting of sampling rate
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
0x0C [ 1:0 ]
0x0
48kHz
0x1
44.1kHz
0x2
32kHz
The constraints of a high speed or a low-speed condition
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
0x0A [ 2 ]
0x0
±10%
We can check detection result by reading back.
The result judged that is once unusual is not cleared until it transmits a clear command, even if the condition of a clock
returns to normal. We can set up
We can set up the constraints of the count of formation, and it does not set a flag until it detects it by count continuation.
BCLK high speed flag
Read Only
Select Address
Value
Operation
0x0A [ 1 ]
0x0
Normal
0x1
High speed detection flag
BCLK low speed flag
Read Only
Select Address
Value
Operation
0x0B [ 1 ]
0x0
Normal
0x1
Low speed detection flag
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BM28720MUV
TSZ02201-0C1C0E900060-1-2
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© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
High speed detection clear register
Write Only
Select Address
Operation
0x0A [ 0 ]
If 1 is written in, a high speed detection flag will be cleared.
※When using a clock error auto return function (P.59), this flag is cleared automatically.
Low speed detection clear register
Write Only
Select Address
Operation
0x0B [ 0 ]
If 1 is written in, a high speed detection flag will be cleared.
※When using a clock error auto return function (P.59), this flag is cleared automatically.
A constraint of the count of judging with high speed flag detection
Default = 0x2 *Blue square means initial value.
Select Address
Operation
0x0A [ 6:4 ]
Please set more than 1.
A constraint of the count of judging with low speed flag detection
Default = 0x2 *Blue square means initial value.
Select Address
Operation
0x0B [ 6:4 ]
Please set more than 1.
High speed detection flag valid or invalid
Default = 0x0 *Blue square means initial value.0x0h
Select Address
Value
Operation
0x0A [ 7 ]
0x0
Valid
0x1
Invalid
Low speed detection flag valid or invalid
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
0x0B [ 7 ]
0x0
Valid
0x1
Invalid
The frequency range of BCLK by which high speed detection or low speed detection is carried out becomes below.
Setting1
Settin2
Low detection
lowest frequency
(MHz)
High detection
highest frequency
(MHz)
64fs BCLK(0x03[ 5:4 ]=0x0)
48kHz(0x0C[1:0]=0x0)
1.28
7.13
44.1kHz(0x0C[1:0]=0x1)
1.21
6.55
32kHz(0x0C[1:0]=0x2)
0.88
4.76
48fs BCLK(0x03[ 5:4 ]=0x1)
48kHz(0x0C[1:0]=0x0)
0.96
5.35
44.1kHz(0x0C[1:0]=0x1)
0.91
4.92
32kHz(0x0C[1:0]=0x2)
0.66
3.57
32fs BCLK(0x03[ 5:4 ]=0x2)
48kHz(0x0C[1:0]=0x0)
0.64
3.56
44.1kHz(0x0C[1:0]=0x1)
0.60
3.28
32kHz(0x0C[1:0]=0x2)
0.44
2.38
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© 2013 ROHM Co., Ltd. All rights reserved.
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TSZ22111 • 15 • 001
6．Auto recovery from clock error function
If clock error is detected, immediately output is muted.
In that case, if the clock error auto return function is enabled, when it returns to a normal input, a mute condition will be
canceled automatically.
If the clock error auto return function is OFF, it is necessary to clear these error flag manually.
Since it is invalid at initial state, we recommend to send 0x0D[6] = 0x1 and to enable auto recovery function.
Valid or invalid auto recover from clock error
Default = 0x0 *Blue square means initial value.
Select Address
Value
Operation
0x0D [ 6 ]
0x0
Invalid
0x1
Valid
Each error flag can be read from the following addresses. When 1 is read from a read address, the error flag stands. Error
flag is not cleared automatically until this register is cleared manually.
Error flag read register
Select Address
Operation
0x0E [ 6 ]
Asynchronous flag
0x0E [ 4 ]
LRCLK stop flag
0x0E [ 3 ]
BCLK stop flag
0x0E [ 2 ]
BCLK high speed detection flag
0x0E [ 1 ]
BCLK low speed detection flag
7．The wake-up Procedure of power-up
It recommends starting power-up in the following Procedures.
1. Power up
Wait over 10ms
2. Release reset(RSTX=H)
Wait over 1ms
3. 0x0C[1:0]=0x* ： Sampling rate(Please set up 0x0 in the case of 48kHz, set up 0x1 in the case of
44.1kHz and 0x02 in 32kHz.)
Please input BCLK and LRCLK
4. 0xE9=0x10 ： changing clock to normal state
Wait over 100ms
5. 0x01=0x00 ： Set RAM clear OFF
6. 0x0D=0x40 ： Valid auto recover from clock error
7. 0x0E=0x00 ： Clear error flag
8. 0x92=0x11 ： PWM setting1
9. 0x93=0x1C ： PWM setting2
10. 0x94=0x15 ： PWM setting3
11. 0x95=0x04 ： PWM setting4
12. Please set up DSP function such as volume, PEQ, DRC, and Scaler etc.
13. MUTEX=high ： Release mute
* The wait time, Twait, is necessary between 2 and 13.(Please refer to P15 for Twait)
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10.Jun.2016 Rev.003
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TSZ22111 • 15 • 001
8．The operating procedure in a status with an unstable clock
In the period which I2S input may become unstable, please set to MUTEX=low and carry out mute.
1. Set MUTEX=low
2. Please wait over 20ms after stabilizing I2S input.
2. Set MUTEX=high
(Note 1)When clock stop was detected, mute release procedure world follow clock stop error release condition.
BCLK
LRCLK
SDATA
MUTEX
Speaker
BTL output
(After LC filter)
PWM stop time
Soft mute
transition
time
Over 20ms
Stable Unstable Stable
Figure 68.
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TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
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TSZ22111 • 15 • 001
9．I2S Data output select
Output I2S data signal From SDATAO (pin12). That SDATAO synchronize to inputted LRCK and BCK signal.
And enable to select output SDATA signal as shown below.
Whatever output is selected, hard clip is processed.
SDATAO output select
Default = 0x0 *Blue square means initial value.
Select Address
Value
Explanation of operation
0x78 [ 6:4 ]
0x0
DSP output (point1)
0x1
DSP input (pont2)
0x2
Pre Scaler output (point3)
0x3
Mixer output (point4)
0x4
12 Band PEQ output (point5)
0x5
Fine Master Volume output (point6)
0x6
No use
0x7
Fine Post Scaler output (point7)
Figure 69.
Input1 Main
Pre
Scaler
Fine
Master
Volum
e/ch
Fine
Post
Scaler/
ch
DC Cut
HPF Hard
Clipper
I2S
LJ
RJ
3Band
DRC
Chanel
Mixer Post
Scaler
12Band
/ch BQ
Point1
Point2
Point3
Point4
Point5
Point6
Point7
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10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Parts Qty Parts No. Description Company Product No.
Inductor 4 L16, L20, L21, L25 10μH / (±20%) / 7.6mm×7.6mm TOKO B1047AS-100M
4
R16, R20
R21, R25 5.6Ω / 1/10W / J(±5%) / 1.6mm×0.8mm MCR03EZPJ5R6
1
R6 1.5kΩ / 1/16W / F(±1%) / 1.0mm×0.5mm MCR01MZPF1501
2
R31, R32 10kΩ / 1/16W / J(±5%) / 1.0mm×0.5mm MCR01MZPJ103
4
R2, R3, R4, R12 0Ω / 1/10W / J(±5%) / 1.6mm×0.8mm MCR03EZPJ000
1 R13 100kΩ / 1/16W / J(±5%) / 1.0mm×0.5mm MCR01MZPJ104
4
C16B, C20B
C21B, C25B
680pF / 50V / B(±10%） / 1.6mm×0.8mm GRM188B11H681KA01
1
C6A 2700pF / 6.3V / B(±10%） / 0.6mm×0.3mm GRM033B10J272KA01
1
C6B 0.027μF / 6.3V / B(±10%） / 0.6mm×0.3mm GRM033B10J273KE01
4
C16A, C20A,
C21A, C25A,
0.33μF / 50V / B(±10%） / 2.0mm×1.25mm GRM219B31H334KA87
2
C17A, C24A (Note 1) 1μF / 50V / B(±10%） / 2.0mm×1.25mm GRM21BB31H105KA12
4
C15, C19,
C22, C26 3.3μF / 16V / B(±10%） / 1.6mm×0.8mm GRM188B31A335KE15
2
C7, C10 1μF / 10V / B(±10%） / 1.6mm×0.8mm GRM185B31A105KE25
1
C27 10μF / 10V / B(±10%) / 1.6mm×0.8mm GRM188B31A106KE69
2
C17B, C24B 100μF / 35V / (±20%) / φ6.3mm×11.2mm PANASONIC ECA1VMH101
Capacitor
MURATA
Resistor
ROHM
Application Circuit Example1 (Stereo BTL output, RL=8Ω, Vcc=10V to 18V)
・When using at Vcc>18V, fc of the LC filter should be lowered to about 60kHz and decrease the influence of LCR resonance
using application circuit. Please refer 5) Output LC Filter Circuit (Vcc>18V)
BOM list1(Stereo BTL output, RL=8Ω, Vcc=10V to 18V)
(Note 1) Please put the C17A and C24A near the VCCP1 and VCCP2 pins on the board.
Figure 70.
Slave
Address
Select
DVDD
VSS
SCL
SDA
SDATA
LRCLK
RSTX
BCLK
Digital
Audio
Source
MCU
MUTEＸ
DVDD DVDD
VSS
VSS
R31R32
C6A
C6B R6
C10
C7
VCCP2
GNDP2
DVDD
ERROR
GNDP1
C27
GNDP2
SP ch2
(Rch)
VSS
C17B
100μF
C17A
R3 0
R4 0
R12
0Ω
1.5kΩ
0.027μF
2700pF
1μF
10μF
R13
100kΩ
C16A
0.33μF
C20A
0.33μF
C16B
680pF
C20B
680pF
R16
5.6Ω
R20
5.6Ω
L16
10μH
L20
10μH
1μF
10kΩ
10kΩ
R2 0
DVDD(3.3V)
C19
C15
3.3μF
3.3μF
1514131211109
1
2
3
4
5
6
7
8
32 31 30 29 28 27 26 25
24
23
22
21
20
19
18
17
16
BSP1P
GNDP1
REG_G
Driver
FET 2N
VCCP2
GNDP2
Driver
FET 2P
PWM
Modulator
Control
I/F
Protection
2 wire I/F
SDATAO
Audio
DSP
I2S/LJ/RJ
I/F
DGND
8 Times
Over-
Sampling
Digital
Filter
REG15
DVDD
PLL
SCL
SDA
ADDR
SDATA
LRCLK
PLL
ERROR OUT2N
OUT2P
BSP1N
OUT1P
MUTEX
RSTX
NC
BSP2N
BSP2P
NC
OUT1N
VCCP1
BCLK
TEST3TEST2
TEST1
VSSVSS
VSS
VSS
MCU SDATAO
LRCLK
BCLK
1μF
VCCP1
GNDP1
GNDP1
SP ch1
(Lch)
C24B
100μF
C24A
C25A
0.33μF
C21A
0.33μF
C25B
680pF
C21B
680pF
R25
5.6Ω
R21
5.6Ω
L25
10μH
L21
10μH
C22
C26
3.3μF
3.3μF
1μF
Driver
FET 1P
Driver
FET 1N
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TSZ02201-0C1C0E900060-1-2
10.Jun.2016 Rev.003
© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Parts Qty Parts No. Description Company Product No.
Inductor 2 L21, L25 10μH / (±20%) / 7.6mm×7.6mm TOKO B1047AS-100M
2
R21, R25 5.6Ω / 1/10W / J(±5%) / 1.6mm×0.8mm MCR03EZPJ5R6
1
R6 1.5kΩ / 1/16W / F(±1%) / 1.0mm×0.5mm MCR01MZPF1501
2
R31, R32 10kΩ / 1/16W / J(±5%) / 1.0mm×0.5mm MCR01MZPJ103
4
R2, R3, R4, R12 0Ω / 1/10W / J(±5%) / 1.6mm×0.8mm MCR03EZPJ000
1 R13 100kΩ / 1/16W / J(±5%) / 1.0mm×0.5mm MCR01MZPJ104
2
C21B, C25B 680pF / 50V / B(±10%） / 1.6mm×0.8mm GRM188B11H681KA01
1
C6A 2700pF / 6.3V / B(±10%） / 0.6mm×0.3mm GRM033B10J272KA01
1
C6B 0.027μF / 6.3V / B(±10%） / 0.6mm×0.3mm GRM033B10J273KE01
2
C21A, C25A 0.33μF / 50V / B(±10%） / 2.0mm×1.25mm GRM219B31H334KA87
1
C24A (Note 1) 1μF / 50V / B(±10%） / 2.0mm×1.25mm GRM21BB31H105KA12
2
C22, C26 3.3μF / 16V / B(±10%） / 1.6mm×0.8mm GRM188B31A335KE15
2
C7, C10 1μF / 10V / B(±10%） / 1.6mm×0.8mm GRM185B31A105KE25
1
C27 10μF / 10V / B(±10%) / 1.6mm×0.8mm GRM188B31A106KE69
1
C24B 100μF / 35V / ±20% / φ6.3mm×11.2mm PANASONIC ECA1VMH101
Capacitor
MURATA
Resister
ROHM
Application Circuit Example2 (Monaural BTL output, RL=8Ω, Vcc=10V to 18V)
・When using at Vcc>18V, fc of the LC filter should be lowered to about 60kHz and decrease the influence of LCR resonance
using application circuit. Please refer 5) Output LC Filter Circuit (Vcc>18V)
BOM list2(Monaural BTL output, RL=8Ω, Vcc=10V to 18V)
(Note 1) Please put the C24A near the VCCP1 pins on the board.
Figure 71.
Slave
Address
Select
DVDD
VSS
SCL
SDA
SDATA
LRCLK
RSTX
BCLK
Digital
Audio
Source
MCU
MUTEＸ
DVDD DVDD
VSS
VSS
R31R32
C6A
C6B R6
C10
C7
GNDP2
DVDD
ERROR
GNDP1
C27
VSS
R3 0
R4 0
R12
0Ω
1.5kΩ
0.027μF
2700pF
1μF
10μF
R13
100kΩ
1μF
10kΩ
10kΩ
R2 0
DVDD(3.3V)
1514131211109
1
2
3
4
5
6
7
8
32 31 30 29 28 27 26 25
24
23
22
21
20
19
18
17
16
BSP1P
GNDP1
REG_G
Driver
FET 2N
VCCP2
GNDP2
Driver
FET 2P
PWM
Modulator
Control
I/F
Protection
2 wire I/F
SDATAO
Audio
DSP
I2S/LJ/RJ
I/F
DGND
8 Times
Over-
Sampling
Digital
Filter
REG15
DVDD
PLL
SCL
SDA
ADDR
SDATA
LRCLK
PLL
ERROR OUT2N
OUT2P
BSP1N
OUT1P
MUTEX
RSTX
NC
BSP2N
BSP2P
NC
OUT1N
VCCP1
BCLK
TEST3TEST2
TEST1
VSSVSS
VSS
VSS
MCU SDATAO
LRCLK
BCLK
VCCP1
GNDP1
GNDP1
SP ch1
(Lch)
C24B
100μF
C24A
C25A
0.33μF
C21A
0.33μF
C25B
680pF
C21B
680pF
R25
5.6Ω
R21
5.6Ω
L25
10μH
L21
10μH
C22
C26
3.3μF
3.3μF
1μF
Driver
FET 1P
Driver
FET 1N
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TSZ02201-0C1C0E900060-1-2
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© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
Selection of Components Externally Connected (Vcc=10V to 18V)
1) Output LC Filter Circuit
An output filter is required to eliminate radio-frequency components exceeding the audio-frequency region supplied to a
load (speaker). Because this IC uses sampling clock frequency 384kHz(fs=48kHz) in the output PWM signals, the
high-frequency components must be appropriately removed.
This section takes an example of an LC type LPF shown below, in which coil L and capacitor C compose a differential
filter with an attenuation property of -12dB/oct. A large part of switching currents flow to capacitor C, and only a small part
of the currents flow to speaker RL1. This filter reduces unwanted emission this way. In addition, coil L and capacitor Cg
composes a filter against in-phase components, reducing unwanted emission further.
Figure 72.
Following presents output LC filter constants with typical load impedances.
RL
L
Cg
4Ω
10μH
1μF
6Ω
10μH
0.47μF
8Ω
10μH
0.33μF
Use coils with a low direct-current resistance and with a sufficient margin of allowable currents. A high direct-current
resistance causes power losses. In addition, select a closed magnetic circuit type product in normal cases to prevent
unwanted emission.
Use capacitors with a low equivalent series resistance, and good impedance characteristics at high frequency ranges
(100kHz or higher). Also, select an item with sufficient withstand voltage because flowing massive amount of
high-frequency currents is expected.
2) The value of the LC filter circuit computed equation
The output LC filter circuit of BM28720MUV is as it is shown in Figure 73. The LC filter circuit of Figure 73 is
thought to substitute it like Figure 74 on the occasion of the computation of the value of the LC filter circuit.
Figure 73. Output LC filter 1 Figure 74. Output LC filter 2
RL
Cg
L
Cg
L
OUTN
OUTP
R
L
Cg
L
Cg
L
OUT
+
OUT
-
Cg
L
OUT
+
OUT
-
or
R
L
R
=
2
1
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© 2013 ROHM Co., Ltd. All rights reserved.
www.rohm.com
TSZ22111 • 15 • 001
The transfer function H(s) of the LC filter circuit of Figure 74 becomes the following.
The ω and Q become the followings here.
Therefore, L and Cg become the followings.
The RL and L should be made known, and fc is set up, and Cg is decided.
3) The settlement of the L value of the coil
For selection of the L value of a coil, please consider side effect as shown below.
①When L value was made small.
(1) Circuit electric currents increase without a signal. And, efficiency in the low output gets bad.
(2) Direct current resistance value is restrained small when the coil of other L value and size are made the same.
Therefore, maximum output is easy to take out. And, it can be used in the low power supply voltage because DC
electric current (allowable electric current) value can be taken greatly.
②When L value was made large.
(1) Circuit electric current is restrained low without a signal. Efficiency in the low output improves.
(2) Direct current resistance value grows big when the coil of other L value and size are made the same. Therefore,
maximum output is hard to take out. And, because it becomes small, use becomes difficult 【 the DC electric
current (allowable electric current) value 】 in the low power supply voltage, too.
4) The settlement of the fC
As for the settlement of the fixed number of the LC filter circuit, it is taken into consideration about two points of the
following, and set up.
①The PWM sampling frequency fPWM (=8fS) of BM28720MUV is set up in 384kHz (@fS=48kHz).
It is set up with fC < fPWM to restrain career frequency omission after the LC filter circuit.
②When fc is lowered too much, the voltage profit of the voice obi stage (especially, the neighborhood of 20kHz)
declines in the speaker output frequency character of the difference movement mode.
And, the speaker output frequency character of the difference movement mode becomes the following.
RL=8Ω
RL=6Ω
RL=4Ω
L[μH]
Cg[μF]
fc[kHz]
L[μH]
Cg[μF]
fc[kHz]
L[μH]
Cg[μF]
fc[kHz]
L[μH]
Cg[μF]
fc[kHz]
10
0.1
75.32
0.40
10
0.1
51.01
0.30
10
0.1
32.19
0.20
0.15
80.85
0.49
0.15
54.76
0.37
0.15
33.35
0.24
0.22
86.79
0.59
0.22
56.73
0.44
0.22
34.55
0.30
0.33
89.92
0.73
0.33
63.1
0.54
0.33
35.8
0.36
0.47
86.79
0.87
0.47
66.68
0.65
0.47
38.37
0.43
1.0
69.01
1.26
1.0
62.29
0.95
1.0
44.1
0.63
15
0.1
46.99
0.33
15
0.1
33.11
0.24
15
0.1
21.68
0.16
0.15
49.66
0.40
0.15
34.36
0.30
0.15
22.08
0.20
0.22
53.46
0.48
0.22
35.65
0.36
0.22
22.49
0.24
0.33
57.54
0.59
0.33
38.37
0.44
0.33
22.91
0.30
0.47
59.7
0.71
0.47
41.3
0.53
0.47
23.77
0.35
1.0
52.75
1.03
1.0
44.67
0.77
1.0
27.47
0.52
22
0.1
30.76
0.27
22
0.1
22.49
0.20
22
0.1
14.72
0.13
0.15
31.92
0.33
0.15
22.91
0.25
0.15
14.72
0.17
0.22
33.73
0.40
0.22
23.77
0.30
0.22
15
0.20
0.33
36.31
0.49
0.33
24.66
0.37
0.33
15.28
0.24
0.47
39.08
0.58
0.47
26.06
0.44
0.47
15.56
0.29
1.0
39.30
0.85
1.0
30.05
0.64
1.0
17.33
0.43
5) Output LC Filter Circuit (Vcc>18V)
22
2
2Q
11
1
)(
ss
LC
s
RC
s
LC
sH
gg
g
g
LC
1
2
L
C
R
L
C
RQ g
L
g2
1
Qf
R
C
L
C
L
g
4
1
2
LC
gRfQ
R
Q
C
C
f
2
g
CLC
f
2
1
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TSZ22111 • 15 • 001
When using at Vcc>18V, fc of the LC filter should be lowered to about 60kHz or less and decrease the influence of
LCR resonance using application circuit.
RL1
L
C
4Ω
10μH
1μF
6Ω
15μH
0.47μF
8Ω
15μH
0.33μF
22μH
0.47μF
Use coils with a low direct current resistance and with a sufficient margin of allowable currents. A high direct current
resistance causes power losses. In addition, select a closed magnetic circuit type product in normal cases to prevent
unwanted emission.
Use capacitors with a low equivalent series resistance and good impedance characteristics at high frequency ranges
(100kHz or higher). Also, select an item with sufficient voltage rating because massive amount of high frequency
currents flow is expected.
In addition, please do not place the CBTL shown in Figure 75.
When considering only common mode signals, OUTP and OUTN are equal to each other and this circuit is equivalent
to the circuit shown in Figure 76.
Therefore, LC resonance may occur depending on the constant of a LC filter.
Figure 78. Figure 79.
RL
Cg
L
Cg
L
OUTN
OUTP
CBTL
Csnb
Rsnb
Csnb
Rsnb
RL
Cg
L
Cg
L
OUTN
OUTP
CBTL
Csnb
Rsnb
Rsnb
Csnb
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TSZ22111 • 15 • 001
6) The settlement of the snubber
The snubber circuit must be optimized for application circuit to reduce the overshoot and undershoot of output PWM.
① Measure the ringing resonance frequency f1 of the PWM output wave shape (When it stands up.) by using
FET probe in the OUT terminal. (Figure 77) The FET probe is to monitor very near pin and shorten ground lead
at the time of that.
② Measure resonance frequency f2 of the ringing as a snubber circuit fixed number R=0Ω. (Only with connecting the
capacitor C to GND) At this time, the value of the capacitor C is adjusted until it becomes half of the frequency
(2f2=f1) of the resonance frequency f1 of ①. The value of C which it could get here is three times of the parasitic
capacity Cp that a ringing is formed. (C=3Cp)
③ Parasitic inductance Lp is looked for at the next formula.
④ The character impedance Z of resonance is looked for from the parasitic capacity Cp and the parasitism
inductance Lp at the next formula.
⑤ A snubber circuit fixed number R is set up in the value which is the same as the character impedance Z.
A snubber circuit fixed number C is set up in the value of 4-10 times of the parasitic capacity Cp. (C=4Cp to 10Cp)
Decide it with trade-off with the character because switching electric currents increase when the value of C is
enlarged too much.
Following presents snubber filter constants with the recommendation value at ROHM 4 layer board.
RL
Csnb
Rsnb
4Ω
680pF ~ 1200pF, 50V B(±10%)
5.6Ω, 1/10W J(±5%)
6Ω
680pF ~ 1200pF, 50V B(±10%)
5.6Ω, 1/10W J(±5%)
8Ω
680pF ~ 1200pF, 50V B(±10%)
5.6Ω, 1/10W J(±5%)
7) Operating condition with the application component
Parameter
Parts No.
Limit
Unit
Min
Conditions
Min
Typ
Max
Capacitor for BSP
C15, C19,
C22, C26
2.0(Note 1)
3.3
4.5
(Note 2)
µF
Recommend characteristics,
16V ceramic type capacitor
2.0(Note 1)
4.7
6.3
(Note 2)
µF
(Note1) Capacitor value should not be less than a minimum in consideration of temperature characteristics and dc-bias characteristics.
(Note2) It is value in consideration of +/-10% of capacity unevenness, capacity rate of change 22%. Please use the capacitor within this limit.
Figure 78. Snubber schematic
p
Cf 2
1
p2
1
L
p
p
C
L
Z
Figure 77. PWM Output waveform
(Measure of ringing resonance frequency
Ringing resonance frequency
5ns/div
VCCP
Cg
Driver
GNDP
Csnb
Rsnb
Snubber LC filter
OUT端子
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TSZ22111 • 15 • 001
Level Diagram of Audio Signal
Level diagram of audio signal is shown the below figure. Speaker output level is depended on I2S digital audio input level,
DSP gain, PWM gain, BTL gain and Loss of power stage and low pass filter.
I2S input level is full-scale signal, the supply voltage of the block is DVDD, and therefore, 0dBFS is equal to DVDD voltage
[Vpp]. DSP gain is set by 2 wire control variably, and -0.3dB is set at PWM Modulator block usually. At the Power stage, the
PWM Modulator output is shifted PWM signal level from DVDD to VCC, and added loss of the output transistor resistance
rDS and DC resistance of coil rDC.
I2S-IF
LRCLK
BCLK
Sync.
SRC
24
24
x8 over
Sampling
DF
PWM
Modulator
Power
Stage
L+
L-
R+
R-
24
24
24
24 Audio
DSP
24
24
SDATA
(1) DSP Gain
(2) PWM Gain
(4) BTL Gain
I2S Input Level
3.3V PWM signal
(×2)
)
200.3-GD
(
10
)
20
VIN
(
10
22
VCC
Output
LPF
Output
LPF
LDCDS
L
Rrr
R
)(2
(3) Loss of
rDS and rDC
10～24V
PWM signal
Figure 79. Level Diagram of Audio Signal
RL
VCC
ON
OFF
rDS rDC rDC
rDS
VCC
ON
OFF
Cg Cg
Figure 80. Output LPF circuit
In Bridge-Tied-Load (BTL) connection, the following formula gives an approximate value of output power Po at non-clipping
output waveform:
VIN : I2S Input level [dBFS]
GD : DSP gain [dB]
VCC : Power supply voltage of Power stage [V]
DVDD : Power supply voltage of DSP block [V]
RL : Load impedance [Ω]
rDS : Turn-on resistance of output MOS Tr. [Ω]
(typ.=160m
Ω
)
rDC : DC resistance of output LPF coil [Ω]
If the circuit is driven further until an output waveform is clipped, an output power higher than that without distortion is
obtained. In general a clipped output is quantified where “THD+N = 1% and 10%,” and a maximum output power under that
status is calculated by the following formula:
][
)
)(2
2
VCC
10(2)203.0-(
%)1( W
RRrr R
PL
DCDS L
L
O
[W]25.1×=PP%)1O(%)10O(
I2S Input
Level
DSP Gain
PWM
Gain
BTL
Gain
Loss of rDS and rDC
LRRrr RVCC
PLDCDS
L
GD
VIN
O
2200.3
20 )
)(2
2
22
1010(
－
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TSZ22111 • 15 • 001
Power Dissipation
Measuring instrument：TH-156(Shibukawa Kuwano Electrical Instruments Co, Ltd.)
Measuring conditions：Installation on ROHM’s board
Board size：74.2mm×74.2mm×1.6mm(with thermal via on board)
Material：FR4
・The board on exposed heat sink on the back of package are connected by soldering.
PCB1：4- layer board (Top and bottom layer back copper foil size: 20.2mm2, 2nd and 3rd layer
back copper foil size: 5505mm2) , θja = 38.3°C/W
PCB2：4-layer board(back copper foil size: 5505mm2), θja = 27.4°C/W
Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating conditions.
This IC exposes its frame of the backside of package. Note that this part is assumed to use after providing heat dissipation
treatment to improve heat dissipation efficiency. Try to occupy as wide as possible with heat dissipation pattern not only on
the board surface but also the backside.
Class D speaker amplifier is high efficiency and low heat generation by comparison with conventional Analog power
amplifier. However, In case it is operated continuously by maximum output power, Power dissipation (Pdiss) may exceed
package dissipation. Please consider about heat design that Power dissipation (Pdiss) does not exceed Package
dissipation (Pd) in average power (Poav). (Tjmax ：Maximum junction temperature=150°C, Ta ：Peripheral temperature[°C],
θja ：Thermal resistance of package[°C/W], Poav：Average power[W], η：Efficiency)
Package dissipation : Pd(W)=(Tjmax - Ta)／θja
Power dissipation : Pdiss(W)= Poav ×(1／η- 1)
PCB② 4.56W
PCB① 3.26W
VQFN032V5050
Figure 81. Allowable Power Dissipation
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
0
25
50
75
100
125
150
Ta [
℃
]
Pd [W]
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TSZ22111 • 15 • 001
I/O equivalence circuit (Provided pin voltages are typ. Values)
Pin
No.
Pin name
Pin voltage
Pin explanation
Internal equivalence circuit
29
30
RSTX
MUTEX
0V
0V
Reset pin for digital circuit
High : Reset OFF
Low : Reset ON
Speaker output mute control pin
High : Mute OFF
Low : Mute ON
29,30
10
8
8
DGND
0V
GND pin for Digital I/O
－
31
SCL
－
2 wire Bus control transmit clock input pin
・Please notice.
Absolute Maximum Voltage is 4.5V.
31
8
32
SDA
－
2 wire Bus control data input/output pin
・Please notice.
Absolute Maximum Voltage is 4.5V.
32
8
1
ADDR
0V
2 wire Bus control Slave address select pin
Select LSB data of slave address for 2 wire
Bus control.
1
10
8
2
BCLK
3.3V
Digital sound bit clock input pin
Input bit clock of digital audio signal.
2
8
10
4
3
SDATA
LRCLK
3.3V
Digital sound signal input pin
Input LR clock of digital audio signal to
LRCLK terminal.
Input data of digital audio signal to SDATA
terminal.
3,4
8
10
12
SDATAO
3.3V
Digital sound signal output pin
Output data of digital audio signal.
12
8
10
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TSZ22111 • 15 • 001
I/O equivalence circuit (Provided pin voltages are typ. Values)
Pin
No.
Pin name
Pin
voltage
Pin explanation
Internal equivalence circuit
6
PLL
1V
PLL’s filter pin
Connect filter circuit for PLL.
6
10
8
10
DVDD
3.3V
Power supply pin for Digital I/O.
－
5
9
11
TEST1
TEST2
TEST3
－
－
－
Test pin
Connect VSS.
10
5,9,11
8
7
REG15
1.5V
Internal power supply pin for Digital
circuit
Connect capacitor.
7
10
8
13
ERROR
3.3V
Error flag pin
H: Normal operation
L: Error
500
13
8
14
28
NC
－
No connection Pin
－
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TSZ22111 • 15 • 001
I/O equivalence circuit (Provided pin voltages are typ. Values)
Pin
No.
Pin name
Pin voltage
Pin explanation
Internal equivalence circuit
17
VCCP2
VCC
Power supply pin for ch2 PWM signal
17
18
15, 19
16, 20
20
OUT2P
VCC to 0V
Output pin of ch2 positive PWM
Connect output LPF.
19
BSP2P
－
Boot-strap pin of ch2 positive
Connect capacitor.
18
GNDP2
0V
GND pin for ch2 PWM signal
16
OUT2N
VCC to 0V
Output pin of ch2 negative PWM
Please connect to Output LPF.
15
BSP2N
－
Boot-strap pin of ch2 negative
Connect capacitor.
22
BSP1N
－
Boot-strap pin of ch1 negative
Connect capacitor.
24
23
22, 26
21, 25
21
OUT1N
VCC to 0V
Output pin of ch1 negative PWM
Connect output LPF.
23
GNDP1
0V
GND pin for ch1 PWM signal
26
BSP1P
－
Boot-strap pin of ch1 positive
Connect capacitor.
25
OUT1P
VCC to 0V
Output pin of ch1 positive PWM
Connect output LPF.
24
VCCP1
VCC
Power supply pin for ch1 PWM signal
27
REG_G
5.7V
Internal power supply pin for gate driver
Connect capacitor.
370K
24
27
23
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TSZ22111 • 15 • 001
Operational Notes
1 ) Absolute maximum ratings
Use of the IC in excess of absolute maximum ratings such as the applied voltage or operating temperature range may
result in IC damage. Assumptions should not be made regarding the state of the IC (short mode or open mode) when
such damage is suffered. A physical safety measure such as a fuse should be implemented when use of the IC in a
special mode where the absolute maximum ratings may be exceeded is anticipated.
2 ) Power supply lines
As return of current regenerated by back EMF of output coil happens, take steps such as putting capacitor between
power supply and GND as an electric pathway for the regenerated current. Be sure that there is no problem with each
property such as emptied capacity at lower temperature regarding electrolytic capacitor to decide capacity value. If the
connected power supply does not have sufficient current absorption capacity, regenerative current will cause the voltage
on the power supply line to rise, which combined with the product and its peripheral circuitry may exceed the absolute
maximum ratings. It is recommended to implement a physical safety measure such as the insertion of a voltage clamp
diode between the power supply and GND pins.
3 ) GND potential (Pin 8, 18, 23)
Any state must become the lowest voltage about DGND, GNDP1 and GNDP2 terminal.
4 ) Input terminal
The parasitic elements are formed in the IC because of the voltage relation. The parasitic element operating causes the
wrong operation and destruction. Therefore, please be careful so as not to operate the parasitic elements by impressing
to input terminals lower voltage than DGND and VSS. Please do not apply the voltage to the input terminal when the
power-supply voltage is not impressed.
5 ) Actions in strong magnetic field
Use caution when using the IC in the presence of a strong magnetic field as doing so may cause the IC to malfunction.
6 ) Thermal shutdown circuit
This product is provided with a built-in thermal shutdown circuit. When the thermal shutdown circuit operates, the output
transistors are placed under open status. The thermal shutdown circuit is primarily intended to shut down the IC avoiding
thermal runaway under abnormal conditions with a chip temperature exceeding Tjmax = 150℃.
7 ) Shorts between pins and miss-installation
When mounting the IC on a board, pay adequate attention to orientation and placement discrepancies of the IC. If it is
miss-installed and the power is turned on, the IC may be damaged. It also may be damaged if it is shorted by a foreign
substance coming between pins of the IC or between a pin and a power supply or a pin and a GND.
8 ) Power supply on/off (Pin 10, 17, 24)
In case power supply is started up, RSTX(Pin 29) and MUTEX(Pin 30) always should be set Low. And in case power
supply is shut down, it should be set Low likewise. Then it is possible to eliminate pop noise when power supply is turned
on/off. And also, all power supply terminals should start up and shut down together.
9 ) ERROR terminal (Pin 13)
An error flag is outputted when Output short protection or DC voltage protection. This flag is the function which the
condition of this product is shown in.
10 ) N.C. terminal (Pin 14, 28)
N.C. terminal (Non Connection Pin) does not connect to the inside circuit. Therefore, possible to use open.
11 ) TEST terminal (Pin 5, 9, 11)
TEST terminal connects with ground to prevent the malfunction by external noise.
12 ) Precautions for Speaker-setting
If the impedance characteristics of the speakers at high-frequency range while increase rapidly, the IC might not have
stable-operation in the resonance frequency range of the LC-filter. Therefore, consider adding damping-circuit, etc.,
depending on the impedance of the speaker.
13 ) External capacitor
In order to use a ceramic capacitor as the external capacitor, determine the constant with consideration given to
a degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature, etc.
14 ) About the rush current
For ICs with more than one power supply, it is possible that rush current may flow instantaneously due to the internal
powering sequence and delays. Therefore, give special consideration to power coupling capacitance, power wiring,
width of GND wiring, and routing of wiring.
Status of this document
The Japanese version of this document is formal specification. A customer may use this translation version
only for a reference to help reading the formal version.
If there are any differences in translation version of this document formal version takes priority
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TSZ22111 • 15 • 001
Ordering Information
BM28720MUV
-
E2
Package
MUV:
VQFN032V5050
Packaging and forming specification
E2: Embossed tape and reel
Physical Dimensions Tape and Reel Information
Marking Diagram
VQFN032V5050 (TOP VIEW)
M28720
Part Number Marking
LOT Number
1PIN MARK
Figure 82.
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TSZ22111 • 15 • 001
Revision History
Date
Revision
Changes
21.Oct.2013
001
First version
10.Dec.2013
002
Corrected (P.2)
Corrected performance curves (P.5-7)
Modified recommend constant (P.63-64, 67, 68)
Deleted application circuit (P.63-64)
10.Jun.2016
003
Modify electric characteristics, condition, explanation of command
Correction of errors
Modify power up sequence(P.22)
Modify procedure for power up(P.59)
Notice-PGA-E Rev.003
© 2015 ROHM Co., Ltd. All rights reserved.
Notice
Precaution on using ROHM Products
1. Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,
OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you
intend to use our Products in devices requiring extremely high reliability (such as medical equipment (Note 1), transport
equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car
accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or
serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.
Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any
damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific
Applications.
(Note1) Medical Equipment Classification of the Specific Applications
JAPAN
USA
EU
CHINA
CLASSⅢ
CLASSⅢ
CLASSⅡb
CLASSⅢ
CLASSⅣ
CLASSⅢ
2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor
products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate
safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which
a failure or malfunction of our Products may cause. The following are examples of safety measures:
[a] Installation of protection circuits or other protective devices to improve system safety
[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure
3. Our Products are designed and manufactured for use under standard conditions and not under any special or
extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way
responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any
special or extraordinary environments or conditions. If you intend to use our Products under any special or
extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of
product performance, reliability, etc, prior to use, must be necessary:
[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents
[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust
[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,
H2S, NH3, SO2, and NO2
[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves
[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items
[f] Sealing or coating our Products with resin or other coating materials
[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of
flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning
residue after soldering
[h] Use of the Products in places subject to dew condensation
4. The Products are not subject to radiation-proof design.
5. Please verify and confirm characteristics of the final or mounted products in using the Products.
6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,
confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power
exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect
product performance and reliability.
7. De-rate Power Dissipation depending on ambient temperature. When used in sealed area, confirm that it is the use in
the range that does not exceed the maximum junction temperature.
8. Confirm that operation temperature is within the specified range described in the product specification.
9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in
this document.
Precaution for Mounting / Circuit board design
1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product
performance and reliability.
2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must
be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products,
please consult with the ROHM representative in advance.
For details, please refer to ROHM Mounting specification
Notice-PGA-E Rev.003
© 2015 ROHM Co., Ltd. All rights reserved.
Precautions Regarding Application Examples and External Circuits
1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the
characteristics of the Products and external components, including transient characteristics, as well as static
characteristics.
2. You agree that application notes, reference designs, and associated data and information contained in this document
are presented only as guidance for Products use. Therefore, in case you use such information, you are solely
responsible for it and you must exercise your own independent verification and judgment in the use of such information
contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses
incurred by you or third parties arising from the use of such information.
Precaution for Electrostatic
This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper
caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be
applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,
isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).
Precaution for Storage / Transportation
1. Product performance and soldered connections may deteriorate if the Products are stored in the places where:
[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2
[b] the temperature or humidity exceeds those recommended by ROHM
[c] the Products are exposed to direct sunshine or condensation
[d] the Products are exposed to high Electrostatic
2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period
may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is
exceeding the recommended storage time period.
3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads
may occur due to excessive stress applied when dropping of a carton.
4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of
which storage time is exceeding the recommended storage time period.
Precaution for Product Label
A two-dimensional barcode printed on ROHM Products label is for ROHM’s internal use only.
Precaution for Disposition
When disposing Products please dispose them properly using an authorized industry waste company.
Precaution for Foreign Exchange and Foreign Trade act
Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign
trade act, please consult with ROHM in case of export.
Precaution Regarding Intellectual Property Rights
1. All information and data including but not limited to application example contained in this document is for reference
only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any
other rights of any third party regarding such information or data.
2. ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the
Products with other articles such as components, circuits, systems or external equipment (including software).
3. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any
third parties with respect to the Products or the information contained in this document. Provided, however, that ROHM
will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to
manufacture or sell products containing the Products, subject to the terms and conditions herein.
Other Precaution
1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.
2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written
consent of ROHM.
3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the
Products or this document for any military purposes, including but not limited to, the development of mass-destruction
weapons.
4. The proper names of companies or products described in this document are trademarks or registered trademarks of
ROHM, its affiliated companies or third parties.
DatasheetDatasheet
Notice – WE Rev.001
© 2015 ROHM Co., Ltd. All rights reserved.
General Precaution
1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.
ROHM shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny
ROHM’s Products against warning, caution or note contained in this document.
2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior
notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s
representative.
3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all
information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or
liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or
concerning such information.
