AK4385ET - Asahi Kasei Corporation

[AK4385]

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GENERAL DESCRIPTION

The AK4385 offers the perfect mix for cost and performance based audio systems. Using AKM's multi bit

architecture for its modulator the AK4385 delivers a wide dynamic range while preserving linearity for

improved THD+N performance. The AK4385 has full differential SCF outputs, removing the need for AC

coupling capacitors and increasing performance for systems with excessive clock jitter. The 24 Bit word

length and 192kHz sampling rate make this part ideal for a wide range of applications including

DVD-Audio. The AK4385 is offered in a space saving 16pin TSSOP package.

FEATURES

 Sampling Rate Ranging from 8kHz to 192kHz

 128 times Oversampling (Normal Speed Mode)

 64 times Oversampling (Double Speed Mode)

 32 times Oversampling (Quad Speed Mode)

 24-Bit 8 times FIR Digital Filter

 On chip SCF

 Digital de-emphasis for 32k, 44.1k and 48kHz sampling

 Soft mute

 Digital Attenuator (Linear 256 steps)

 I/F format: 24-Bit MSB justified, 24/20/16-Bit LSB justified or I2S

 Master clock: 256fs, 384fs, 512fs, 768fs or 1152fs (Normal Speed Mode)

128fs, 192fs, 256fs or 384fs (Double Speed Mode)

128fs, 192fs (Quad Speed Mode)

 THD+N: -94dB

 Dynamic Range: 108dB

 High Tolerance to Clock Jitter

 Power supply: 4.75 to 5.25V

 Very Small Package: 16pin TSSOP (6.4mm x 5.0mm)

 AK4381 Pin Compatible

LRCK

BICK

SDTI

A

udio

Data

Interface

MCLK

PDN

ΔΣ

Modulator AOUTL+

8X

Interpolator SCF

AOUTR+

SCF

V

DD

V

SS

De-emphasis

Control

µP

Interface

Clock

Divider

CSN

CCLK

CDTI

DZF

R

ΔΣ

Modulator

8X

Interpolator

AOUTL-

AOUTR-

DZFL

108dB 192kHz 24-Bit 2ch ΔΣ DAC

AK4385

[AK4385]

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■ Ordering Guide

AK4385ET -20 ∼ +85°C 16pin TSSOP (0.65mm pitch)

AK4385VT -40 ∼ +85°C 16pin TSSOP (0.65mm pitch)

AKD4385 Evaluation Board for AK4385

■ Pin Layout

1

MCLK

LRCK

BICK

CSN

CCLK

CDTI

Top

View

2

3

4

5

6

7

8

DZFL

DZFR

VSS

VDD

A

OUTL+

A

OUTL-

A

OUTR+

A

OUTR-

16

15

14

13

12

11

10

9

PDN

SDTI

PIN/FUNCTION

No. Pin Name I/O Function

1 MCLK I Master Clock Input Pin

An external TTL clock should be input on this pin.

2 BICK I Audio Serial Data Clock Pin

3 SDTI I Audio Serial Data Input Pin

4 LRCK I L/R Clock Pin

5 PDN I Power-Down Mode Pin

When at “L”, the AK4385 is in the power-down mode and is held in reset.

The AK4385 must be reset once upon power-up.

6 CSN I Chip Select Pin

7 CCLK I Control Data Input Pin

8 CDTI I Control Data Input Pin in serial mode

9 AOUTR- O Rch Negative Analog Output Pin

10 AOUTR+ O Rch Positive Analog Output Pin

11 AOUTL- O Lch Negative Analog Output Pin

12 AOUTL+ O Lch Positive Analog Output Pin

13 VSS - Ground Pin

14 VDD - Power Supply Pin

15 DZFR O Rch Data Zero Input Detect Pin

16 DZFL O Lch Data Zero Input Detect Pin

Note: All input pins should not be left floating.

[AK4385]

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ABSOLUTE MAXIMUM RATINGS

(VSS=0V; Note 1)

Parameter Symbol min max Units

Power Supply VDD -0.3 6.0 V

Input Current (any pins except for supplies) IIN - ±10 mA

Input Voltage VIND -0.3 VDD+0.3 V

AK4385ET Ta -20 85

°C

Ambient Operating Temperature

(Powered applied) AK4385VT Ta -40 85

°C

Storage Temperature Tstg -65 150 °C

Note: 1. All voltages with respect to ground.

WARNING: Operation at or beyond these limits may results in permanent damage to the device.

Normal operation is not guaranteed at these extremes.

RECOMMENDED OPERATING CONDITIONS

(VSS=0V; Note 1)

Parameter Symbol min typ max Units

Power Supply VDD 4.75 5.0 5.25 V

*AKM assumes no responsibility for the usage beyond the conditions in this datasheet.

[AK4385]

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ANALOG CHARACTERISTICS

(Ta=25°C; VDD=5.0V; fs=44.1kHz; BICK=64fs; Signal Frequency=1kHz; 24bit Input Data;

Measurement frequency=20Hz ∼ 20kHz; RL ≥4kΩ; unless otherwise specified)

Parameter min typ max Units

Resolution 24 Bits

Dynamic Characteristics (Note 3)

fs=44.1kHz

BW=20kHz 0dBFS

-60dBFS -94

-44 -84

- dB

dB

fs=96kHz

BW=40kHz 0dBFS

-60dBFS -92

-41 -

- dB

dB

THD+N

fs=192kHz

BW=40kHz 0dBFS

-60dBFS -92

-41 -

- dB

dB

Dynamic Range (-60dBFS with A-weighted) (Note 4) 100 108 dB

S/N (A-weighted) (Note 5) 100 108 dB

Interchannel Isolation (1kHz) 90 110 dB

Interchannel Gain Mismatch 0.2 0.5 dB

DC Accuracy

Gain Drift 100 - ppm/°C

Output Voltage (Note 6) ±2.55 ±2.75 ±2.95 Vpp

Load Resistance (Note 7) 4 kΩ

Power Supplies

Power Supply Current (VDD)

Normal Operation (PDN = “H”, fs≤96kHz)

Normal Operation (PDN = “H”, fs=192kHz)

Power-Down Mode (PDN = “L”) (Note 8)

17

20

10

27

32

100

mA

μA

Notes: 3. Measured by Audio Precision (System Two). Refer to the evaluation board manual.

4. 100dB at 16bit data.

5. S/N does not depend on input bit length.

6. Full-scale voltage (0dB). Output voltage scales with the voltage of VREF,

AOUT (typ.@0dB)=(AOUT+)-(AOUT-)=±2.75Vpp × VREF/5.

7. For AC-load. 4kΩ for DC-load.

8. All digital inputs including clock pins (MCLK, BICK and LRCK) are held VDD or VSS.

[AK4385]

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SHARP ROLL-OFF FILTER CHARACTERISTICS

(Ta = 25°C; VDD = 4.75 ∼ 5.25V; fs = 44.1kHz; DEM = OFF; SLOW = “0”)

Parameter Symbol min typ max Units

Digital filter

Passband ±0.05dB (Note 9)

-6.0dB PB 0

-

22.05 20.0

- kHz

kHz

Stopband (Note 9) SB 24.1 kHz

Passband Ripple PR ± 0.02 dB

Stopband Attenuation SA 54 dB

Group Delay (Note 10) GD - 19.3 - 1/fs

Digital Filter + SCF

Frequency Response

20.0kHz

40.0kHz

80.0kHz

fs=44.1kHz

fs=96kHz

fs=192kHz

FR

-

± 0.2

± 0.3

+0.1/-0.6

-

dB

Notes: 9. The passband and stopband frequencies scale with fs(system sampling rate).

For example, PB=0.4535×fs (@±0.05dB), SB=0.546×fs.

10. The calculating delay time which occurred by digital filtering. This time is from setting the 16/24bit data

of both channels to input register to the output of analog signal.

SLOW ROLL-OFF FILTER CHARACTERISTICS

(Ta = 25°C; AVDD, DVDD = 4.75~5.25V; fs = 44.1kHz; DEM = OFF; SLOW = “1”)

Parameter Symbol min typ max Units

Digital Filter

Passband ±0.04dB (Note 11)

-3.0dB PB

0

-

18.2 8.1

- kHz

kHz

Stopband (Note 11) SB 39.2 kHz

Passband Ripple PR ± 0.005 dB

Stopband Attenuation SA 72 dB

Group Delay (Note 10) GD - 19.3 - 1/fs

Digital Filter + SCF

Frequency Response

20.0kHz

40.0kHz

80.0kHz

fs=44.kHz

fs=96kHz

fs=192kHz

FR

-

+0/-5

+0/-4

+0.1/-5

-

dB

Note: 11. The passband and stopband frequencies scale with fs.

For example, PB = 0.185×fs (@±0.04dB), SB = 0.888×fs.

DC CHARACTERISTICS

(Ta=25°C; VDD=4.75 ∼ 5.25V)

Parameter Symbol min typ max Units

High-Level Input Voltage

Low-Level Input Voltage VIH

VIL 2.2

- -

0.8 V

V

High-Level Output Voltage (Iout=-80µA)

Low-Level Output Voltage (Iout=80µA) VOH

VOL VDD-0.4

- - -

0.4 V

V

Input Leakage Current Iin - - ± 10 µA

[AK4385]

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SWITCHING CHARACTERISTICS

(Ta=25°C; VDD=4.75 ∼ 5.25V)

Parameter Symbol min typ max Units

Master Clock Frequency

Duty Cycle fCLK

dCLK 2.048

40 11.2896

36.864

60 MHz

%

LRCK Frequency

Normal Speed Mode

Double Speed Mode

Quad Speed Mode

Duty Cycle

fsn

fsd

fsq

Duty

8

60

120

45

48

96

192

55

kHz

%

Audio Interface Timing

BICK Period

Normal Speed Mode

Double/Quad Speed Mode

BICK Pulse Width Low

Pulse Width High

BICK rising to LRCK Edge (Note 12)

LRCK Edge to BICK rising (Note 12)

SDTI Hold Time

SDTI Setup Time

tBCK

tBCKL

tBCKH

tBLR

tLRB

tSDH

tSDS

1/128fs

1/64fs

30

20

ns

Control Interface Timing

CCLK Period

CCLK Pulse Width Low

Pulse Width High

CDTI Setup Time

CDTI Hold Time

CSN “H” Time

CSN “↓” to CCLK “↑”

CCLK “↑” to CSN “↑”

tCCK

tCCKL

tCCKH

tCDS

tCDH

tCSW

tCSS

tCSH

200

80

40

150

50

ns

Reset Timing

PDN Pulse Width (Note 13)

tPD

150

ns

Notes: 12. BICK rising edge must not occur at the same time as LRCK edge.

13. The AK4385 can be reset by bringing PDN= “L”.

[AK4385]

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■ Timing Diagram

1/fCLK

tCLKL

VIH

tCLKH

MCLK VIL

dCLK=tCLKH x fCLK, tCLKL x fCLK

1/fs

VIH

LRCK VIL

tBCK

tBCKL

VIH

tBCKH

BICK VIL

Clock Timing

tLRB

LRCK

VIH

BICK VIL

tSDS

VIH

SDTI VIL

tSDH

VIH

VIL

tBLR

Serial Interface Timing

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tCSS

CSN

VIH

CCLK VIL

VIH

CDTI VIL

VIH

VIL

C1 C0 R/W A4

tCCKL tCCKH

tCDS tCDH

WRITE Command Input Timing

CSN

VIH

CCLK VIL

VIH

CDTI VIL

VIH

VIL

D3 D2 D1 D0

tCSW

tCSH

WRITE Data Input Timing

tPD

VIL

PDN

Power-down Timing

[AK4385]

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OPERATION OVERVIEW

■ System Clock

The external clocks, which are required t o operate the AK4385, are MCLK, LRCK and BICK. The mast er clock (MCLK)

should be synchronized with LRCK but the phase is not critical. The MCLK is used to operate the digital interpolation

filter and the delta-sigma m odulator. There are two methods to set MCLK frequency. In Manual Setting Mode (ACKS =

“0”: Register 00H), the sampling speed is set by DFS0/1(Table 1). The frequency of MCLK at each sampling speed is set

automatically. (Table 2~4).After exiting reset (PDN = “↑”), the AK4385 is in Auto Setting Mode. In Auto Setting Mode

(ACKS = “1”: Default), as MCLK frequency is detected automatically (Table 5), and the internal master clock becomes

the appropriate frequency (Table 6), it is not necessary to set DFS0 /1.

All external clocks (M CLK,BICK and LRCK) should always be present whenever t he AK4385 is in the normal operation

mode (PDN= ”H”). If these clocks are not provided, the AK4385 may draw excess current and m ay fall into unpredictable

operation. This is because the device utilizes dynamic refreshed logic internally. The AK4385 should be reset by PDN=

“L” after threse clocks are provided. If the external clocks are not present, the AK4385 should be in the power-down

mode (PDN= “L”). After exiting reset at power-up etc., the AK4385 is in the power-down mode until MCLK and LRCK

are input.

DFS1 DFS0 Sampling Rate (fs)

0 0 Normal Speed Mode 8kHz~48kHz Default

0 1 Double Speed Mode 60kHz~96kHz

1 0 Quad Speed Mode 120kHz~192kHz

Table 1. Sampling Speed (Manual Setting Mode)

LRCK MCLK BICK

fs 256fs 384fs 512fs 768fs 1152fs 64fs

32.0kHz 8.1920MHz 12.2880MHz 16.3840MHz 24.5760MHz 36.8640MHz 2.0480MHz

44.1kHz 11.2896MHz 16.9344MHz 22.5792MHz 33.8688MHz N/A 2.8224MHz

48.0kHz 12.2880MHz 18.4320MHz 24.5760MHz 36.8640MHz N/A 3.0720MHz

Table 2. System Clock Example (Normal Speed Mode @Manual Setting Mode)

LRCK MCLK BICK

fs 128fs 192fs 256fs 384fs 64fs

88.2kHz 11.2896MHz 16.9344MHz 22.5792MHz 33.8688MHz 5.6448MHz

96.0kHz 12.2880MHz 18.4320MHz 24.5760MHz 36.8640MHz 6.1440MHz

Table 3. System Clock Example (Double Speed Mode @Manual Setting Mode)

LRCK MCLK BICK

fs 128fs 192fs 64fs

176.4kHz 22.5792MHz 33.8688MHz 11.2896MHz

192.0kHz 24.5760MHz 36.8640MHz 12.2880MHz

Table 4. System Clock Example (Quad Speed Mode @Manual Setting Mode)

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MCLK Sampling Speed

512fs 768fs Normal

256fs 384fs Double

128fs 192fs Quad

Table 5. Sampling Speed (Auto Setting Mode: Default)

LRCK MCLK (MHz)

fs 128fs 192fs 256fs 384fs 512fs 768fs

Sampling Speed

32.0kHz - - - - 16.3840 24.5760

44.1kHz - - - - 22.5792 33.8688

48.0kHz - - - - 24.5760 36.8640

Normal

88.2kHz - - 22.5792 33.8688 - -

96.0kHz - - 24.5760 36.8640 - - Double

176.4kHz 22.5792 33.8688 - - - -

192.0kHz 24.5760 36.8640 - - - - Quad

Table 6. System Clock Example (Auto Setting Mode)

■ Audio Serial Interface Format

Data is shifted in via the SDTI pin using BICK and LRCK inputs. The DIF0-2 as shown in Table 7 can select five serial

data modes. In all modes the serial data is MSB-first, 2’s compliment format and is latched on the rising edge of BICK.

Mode 2 can be used for 16/20 MSB justified formats by zeroing the unused LSBs.

Mode DIF2 DIF1 DIF0 SDTI Format BICK Figure

0 0 0 0 16bit LSB Justified ≥32fs Figure 1

1 0 0 1 20bit LSB Justified ≥40fs Figure 2

2 0 1 0 24bit MSB Justified ≥48fs Figure 3 Default

3 0 1 1 24bit I2S Compatible ≥48fs Figure 4

4 1 0 0 24bit LSB Justified ≥48fs Figure 2

Table 7. Audio Data Formats

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SDTI

BICK

LRCK

SDTI 15 14 6 5 4

BICK

0 1 10 11 12 13 14 15 0 1 10 11 12 13 14 15 0 1

3 2 1 0 15 14

(

32fs

)

(

64fs

)

014

115 16 17 31 0 1 14 15 16 17 31 0 1

15 14 0 15 14 0

Mode 0 Don’t care Don’t care

15:MSB, 0:LSB

Mode 0 15 14 6 5 4 3 2 1 0

Lch Data Rch Data

Figure 1. Mode 0 Timing

SDTI

LRCK

BICK

(

64fs

)

091 10 11 12 31 0 1 9 10 11 12 31 0 1

19 0 19 0

Mode 1 Don’t care Don’t care

19:MSB, 0:LSB

SDTI

Mode 4 23:MSB, 0:LSB

20 19 0 20 19 0

Don’t care Don’t care

22 21 22 21

Lch Data Rch Data

8

23 23

8

Figure 2. Mode 1,4 Timing

LRCK

BICK

(

64fs

)

SDTI

0221 2 24 31 0 1 31 0 1

23:MSB, 0:LSB

22 1 0 Don’t care23

Lch Data Rch Data

23 30 2222423 30

22 1 0 Don’t care

23 2223

Figure 3. Mode 2 Timing

[AK4385]

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LRCK

BICK

(

64fs

)

SDTI

031 2 24 31 0 1 31 0 1

23:MSB, 0:LSB

22 10Don’t care

23

Lch Data Rch Data

23 25 322423 25

22 1 0Don’t care23 23

Figure 4. Mode 3 Timing

■ De-emphasis Filter

A digital de-emphasis filter is available for 32, 44.1 or 48kHz sampling rates (tc = 50/15µs) and is enabled or disabled

with DEM0 and DEM1. In case of double speed and quad speed mode, the digital de-emphasis filter is always off.

DEM1 DEM0 Mode

0 0 44.1kHz

0 1 OFF

Default

1 0 48kHz

1 1 32kHz

Table 8. De-emphasis Filter Control (Normal Speed Mode)

■ Output Volume

The AK4385 includes channel independent digital output volumes (ATT) wi th 256 levels at li near step including MUTE.

These volumes are in front of the DAC and can attenuate the input data from 0dB to –48dB and mute. When changing

levels, transitions are executed via soft changes; thus no switching noise occurs during these transitions. The transition

time of 1 level and all 256 levels is shown in Table 9.

Transition Time

Sampling Speed 1 Level 255 to 0

Normal Speed Mode 4LRCK 1020LRCK

Double Speed Mode 8LRCK 2040LRCK

Quad Speed Mode 16LRCK 4080LRCK

Table 9. ATT Transition Time

[AK4385]

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■ Zero Detection

The AK4385 has channel-independent zeros detect function. When the input data at each channel is continuously zeros

for 8192 LRCK cycles, DZF pin of each channel goes to “H”. DZF pin of each channel imme di ately goes to “L” if input

data of each channel is not zero after going DZF “H”. If RSTN bit is “0”, DZF pins of both channels go to “H”. DZF pin

of both channels go to “L” at 2~3/ fs after RSTN bit returns to “1”. If DZFM bit is set to “1”, DZF pins of both channel s go

to “H” only when the input data at both channels are cont inuously zeros for 8192 LR CK cycles. Zero detect function can

be disabled by DZFE bit. In this case, DZF pins of both channels are always “L”. DZFB bit can invert the polarity of DZF

pin.

■ Soft Mute Operation

Soft mute operation is performed at digital domain. When the SMUTE bit goes to “1”, the output signal is attenuated by

-∞ during ATT_DATA×ATT transition time (Table 9) from the current ATT level. When the SMUTE bit is return ed to

“0”, the mute is cancelled and the output attenuation gradually changes to the ATT level during ATT_DATA×ATT

transition time. If the soft mute is cancelled before attenuating to -∞ after starting the operation, the attenuation is

discontinued and returned to ATT level by the same cycle. The soft mute is effective for changing the signal source

without stopping the signal transmission.

SMUTE bit

A

ttenuation

DZF pin

ATT Level

-∞

A

OUT

8192/fs

GD GD

(1)

(2)

(3)

(4)

(1)

Notes:

(1) ATT_DATA×ATT transition tim e (Tabl e 9). For exam pl e, in Norm al Speed M ode, this time is 1020LRCK cycl es

(1020/fs) at ATT_DATA=255.

(2) The analog output corresponding to the digital input has a group delay, GD.

(3) If the soft mute is cancelled before attenuating to -∞ after starting the operation, the att enuation is discontinued and

returned to ATT level by the same cycle.

(4) When the input data at each channel is continuously zeros for 8192 LRCK cycles, DZF pin of each channel goes to

“H”. DZF pin immediately goes to “L” if input data are not zero after going DZF “H”.

Figure 5. Soft Mute and Zero Detection

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■ System Reset

The AK4385 should be reset once by bringing PDN= ”L” upon power-up. The AK4385 is powered up and the internal

timing starts clocking by LRCK “↑” after exiting reset and power down state by MCLK. The AK4385 is in the

power-down mode until MCLK and LRCK are input.

■ Power-down

The AK4385 is placed in the power-down mode by bringing PDN pin “L” and the anlog outputs are floating (Hi-Z).

Figure 6 shows an example of the system timing at the power-down and power-up.

Normal Op eration

Internal

State

PDN

Power-down Normal Operation

GD GD

“0” data

D/A Out

(Analog)

D/A In

(Digital)

Clock In

MCLK, LRCK, BICK

(1) (3)

(6)

DZFL/DZFR

External

MUTE (5)

(3) (1)

Mute ON

(2)

(4)

Don’t care

Notes:

(1) The analog output corresponding to digital input has the group delay (GD).

(2) Analog outputs are floating (Hi -Z) at the power-down mode.

(3) Click noise occurs at the edge of PDN signal. This noise is output even if “0” data is input.

(4) The external clocks (MCLK, BICK and LRCK) can be stopped in the power-down mode (PDN = “L”).

(5) Please mute the analog output externally if the click noise (3) influences system application.

The timing example is shown in this figure.

(6) DZF pins are “L” in the power-down mode (PDN = “L”).

Figure 6. Power-down/up Sequence Example

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■ Reset Function

When RSTN=0, DAC is powered down but the in ternal register values are not initialized. The analog outputs go to

VCOM voltage and DZF pin goes to “H”. Figure 7 shows the example of reset by RSTN bit.

Internal

State

RSTN bit

Digital Block Power-down Normal Op eration

GD GD

“0” data

D/A Out

(Analog)

D/A In

(Digital)

Clock In

MCLK,LRCK,BICK

(1) (3)

DZF

(3) (1)

(2)

Normal Operation

2/fs(5)

Internal

RSTN bit

2~3/fs (6)3~4/fs (6)

Don’t care

(4)

Notes:

(1) The analog output corresponding to digital input has the group delay (GD).

(2) Analog outputs go to VCOM voltage (VDD/2).

(3) Click noise occurs at t he edges(“↑ ↓”) of the internal timing of RSTN bit. This noise is output even if “0” data is

input.

(4) The external clocks (MCLK, BICK and LRCK) can be stopped in the reset mode (RSTN = “L”).

(5) DZF pins go to “H” when the RSTN bit becomes “0”, and go to “L” at 2/fs after RSTN bit becomes “1”.

(6) There is a delay, 3~4/fs from RSTN bit “0” to the internal RSTN bit “0 ”, and 2~3/fs from RSTN bit “1” to the

internal RSTN “1”.

Figure 7. Reset Sequence Example

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■ Mode Control Interface

Internal registers may be written by 3-wire µP interface pins, CSN, CCLK and CDTI. The data on this interface consists

of Chip Addr ess (2bits, C1/0; fixed to “01”), Read/Write (1bit; fixed to “1”, Write only), Register Addr ess (MSB first,

5bits) and Control Dat a (M SB fi rst , 8bi t s ). AK4385 l atches the data on the rising edge of CCLK, so data should clocked

in on the falling edge. The writing of data becomes valid by CSN “↑”. The clock speed of CCLK is 5MHz (max).

PDN = “L” resets the registers to their default values. The internal timing circuit is reset by RSTN bit, but the registers are

not initialized.

CDTI

CCLK

CSN

C1

012345678 9 10 11 12 13 14 15

D4D5D6D7A1A2A3A4R/WC0 A0 D0D1D2D3

C1-C0: Chip Address (Fixed to “01”)

R/W: READ/WRITE (Fixed to “1”, Write o nly)

A4-A0: Register Address

D7-D0: Control Data

Figure 8. Control I/F Timing

*AK4385 does not support the read command and chip address. C1/0 and R/W are fixed to “011”

*When the AK4385 is in the power down mode (PDN = “L”) or the MCLK is not provided, writing into the control

register is inhibited.

■ Register Map

Addr Register Name D7 D6 D5 D4 D3 D2 D1 D0

00H Control 1 ACKS 0 0 DIF2 DIF1 DIF0 PW RSTN

01H Control 2 DZFE DZFM SLOW DFS1 DFS0 DEM1 DEM0 SMUTE

02H Control 3 0 0 0 0 0 DZFB 0 0

03H Lch ATT ATT7 ATT6 ATT5 ATT4 ATT3 ATT2 ATT1 ATT0

04H Rch ATT ATT7 ATT6 ATT5 ATT4 ATT3 ATT2 ATT1 ATT0

Notes:

For addresses from 05H to 1FH, data must not be written.

When PDN pin go es “L”, the registers are initialized to their default valu es.

When RSTN bit g oes “0”, the only internal timing is reset and the registers are not initialized to their default

values.

All data can be written to the register even if PW or RSTN bit is “0”.

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■ Register Definitions

Addr Register Name D7 D6 D5 D4 D3 D2 D1 D0

00H Control 1 ACKS 0 0 DIF2 DIF1 DIF0 PW RSTN

default 1 0 0 0 1 0 1 1

RSTN: Internal timing reset control

0: Reset. All registers are not initialized.

1: Normal Operation

When MCLK frequency or DFS changes, the click noise can be reduced by RSTN bit.

PW: Power down control

0: Power down. All registers are no t initialized.

1: Normal Operation

DIF2-0: Audio data interface formats (see Table 7)

Initial: “010”, Mode 2

ACKS: Master Clock Frequency Auto Setting Mode Enable

0: Disable, Manual Setting Mode

1: Enable, Auto Setting Mode

Master clock frequency is detected automatically at ACKS bit “1”. In this case, the setting of DFS1-0

are ignored. When this bit is “0”, DFS1-0 set the sampling speed mode.

Addr Register Name D7 D6 D5 D4 D3 D2 D1 D0

01H Control 2 DZFE DZFM SLOW DFS1 DFS0 DEM1 DEM0 SMUTE

default 0 0 0 0 0 0 1 0

SMUTE: Soft Mute Enable

0: Normal operation

1: DAC outputs soft-muted

DEM1-0: De-emphasis Response (see Table 8)

Initial: “01”, OFF

DFS1-0: Sampling speed control

00: Normal speed

01: Double speed

10: Quad speed

When changing between Normal/Double Speed Mode and Quad Speed Mode, some click noise

occurs.

SLOW: Slow Roll-off Filter Enab le

0: Sharp Roll-off Filter

1: Slow Roll-off Filter

DZFE: Data Zero Detect Enable

0: Disable

1: Enable

Zero detect function can be disabled by DZFE bi t “0”. In this case, the DZF pins of both channels are

always “L”.

[AK4385]

MS0246-E-02 2010/09

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DZFM: Data Zero Detect Mode

0: Channel Separated Mode

1: Channel ANDed Mode

If the DZFM bit is set to “1”, the DZF pins of both channels go to “H” only when the input data at bot h

channels are continuously zeros for 8192 LRCK cycles.

Addr Register Name D7 D6 D5 D4 D3 D2 D1 D0

02H Control 3 0 0 0 0 0 DZFB 0 0

default 0 0 0 0 0 0 0 0

DZFB: Inverting Enable of DZF

0: DZF goes “H” at Zero Detection

1: DZF goes “L” at Zero Detection

Addr Register Name D7 D6 D5 D4 D3 D2 D1 D0

03H Lch ATT ATT7 ATT6 ATT5 ATT4 ATT3 ATT2 ATT1 ATT0

04H Rch ATT ATT7 ATT6 ATT5 ATT4 ATT3 ATT2 ATT1 ATT0

default 1 1 1 1 1 1 1 1

ATT = 20 log

10 (ATT_DATA / 255) [dB]

00H: Mute

SYSTEM DESIGN

Figure 9 shows the system connection diagram. An evaluation board (AKD4385) is available in order to allow an easy

study on the layout of a surrounding circuit.

MCLK

1

BICK

2

SDTI

3

LRCK

4

PDN

5

CSN

6

CCLK

7

CDTI 8

DZFL 16

DZFR 15

VDD 14

VSS 13

AOUTL+ 12

AOUTL- 11

AOUTR+ 10

AOUTR- 9

Master Clock

Micro-

controller

AK4385

fs

24bit Audio Data

Reset & Power down

64fs

10u

0.1u +

Lch

LPF

Rch

LPF Rch Out

Lch Out

Analog Ground Digital Ground

Lch

MUTE

Rch

MUTE

A

nalog

Supply 5V

Figure 9. Typical Connection Diagram

Notes:

- LRCK = fs, BICK = 64fs.

- When AOUT drives some capacitive load, some resistor should be added in series between AOUT and

capacitive load.

- All input pins should not be left floating.

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MS0246-E-02 2010/09

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1. Grounding and Power Supply Decoupling

VDD and VSS are supplied from analog supply and should be separated from system digital supply. Decoupling

capacitor, especially 0.1μF ceramic capacitor for high frequency should be placed as near to VDD as possible. The

differential Voltage between VDD and VSS pins set the analog output range.

2. Analog Outputs

The analog outputs are full-different ia l out put s and 0.55 x VDD Vpp (typ) centered around t he i nt ernal common vol t age

(about AVDD/2). The differential outputs are summed externally, VAOUT=(AOUT+)-(AOUT-) between AOUT+ and

AOUT-. If the summing gain is 1, the output range is 5.5Vpp (typ @VREFH=5V). The bias voltage of the external

summ ing circuit is suppli ed externally. The i nput data format is 2’s complem ent. The output vol tage (VAOUT) is a positive

full scale for 7FFFFF (@24bit) and a negative full scale for 800000H (@24bit). The ideal VAOUT is 0V for 000000H

(@24bit).

The internal switched-capacitor filter and external low pass filter attenuate the noise generated by the delta-sigma

modulator beyond the audio passband. DC offset on AOUT+/- is eliminated without AC coupling since the analog

outputs are differential . Fi gure 10 and 11 show t he example of external op-amp circuit summing the differentia l outputs.

4.7k 4.7k

R1

4.7k R1

4.7k 470p

Vop

470p

Vop

1k

1k47u

0.1u

BIAS

AOUT-

AOUT+

3300p

When R1=200Ω

When R1=180Ω

fc=93.2kHz, Q=0.712, g=-0.1dB at 40kHz

fc=98.2kHz, Q=0.681, g=-0.2dB at 40kHz

Analog

Out

Figure 10. External 2nd order LPF Circuit Example (using op-amp with single power supply)

4.7k 4.7k

R1

4.7k R1

4.7k 470p

+Vop

470p

-Vop

AOUT-

AOUT+

3300p

When R1=200Ω

When R1=180Ω

fc=93.2kHz, Q=0.712, g=-0.1dB at 40kHz

fc=98.2kHz, Q=0.681, g=-0.2dB at 40kHz

Analog

Out

Figure 11. External 2nd order LPF Circuit Example (using op-amp with dual power supplies)

[AK4385]

MS0246-E-02 2010/09

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PACKAGE

0-10°

Detail A

Seating Plane 0.10

0.17±0.05

0.22±0.1 0.65

*5.0±0.1 1.1 (max)

A

1 8

9 16

16pin TSSOP (Unit: mm)

*4.4±0.1

6.4±0.2

0.5±0.2

0.1±0.1

NOTE: Dimension "*" does not include mold flash.

0.13 M

■ Package & Lead frame material

Package molding compound: Epoxy

Lead frame material: Cu

Lead frame surface treatment: Solder(Pb free) plate

[AK4385]

MS0246-E-02 2010/09

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MARKING (AK4385VT)

AKM

4385VT

XX YYY

1) Pin #1 indication

2) Date Code : XXYYY (5 digits)

XX: Lot#

YYY: Date Code

3) Marketing Code : 4385VT

4) Asahi Kasei Logo

[AK4385]

MS0246-E-02 2010/09

- 22 -

MARKING (AK4385ET)

AKM

4385ET

XX YYY

5) Pin #1 indication

6) Date Code : XXYYY (5 digits)

XX: Lot#

YYY: Date Code

7) Marketing Code : 4385ET

8) Asahi Kasei Logo

[AK4385]

MS0246-E-02 2010/09

- 23 -

REVISION HISTORY

Date (YY/MM/DD) Revision Reason Page Contents

03/07/02 00 First Edition

2 Ordering Guide

AK4385ET was added.

06/01/11 01 Spec Addition

22 MARKING

AK4385ET was added.

10/09/28 02 Specification

Change 20 PACKAGE

The package dimension was changed.

IMPORTANT NOTICE

z These products and their specifications are subject to change without notice.

When you consider any use or application of these products, please make inquiries the sales office of Asahi Kasei

Microdevices Corporation (AKM) or authorized distributors as to current status of the products.

z Descriptions of external circuits, application circuits, software and other related information contained in this

document are provided only to illustrate the operation and application exampl es of the sem iconductor products. You

are fully responsible for the incorporation of these external circuits, application circuits, software and other related

information in the design of your equipments. AKM assum es no responsibility for any losses incurred by you or third

parties arising from the use of these information herein. AKM assumes no liability for infringement of any p atent,

intellectual property, or other rights in the application or use of such information contained herein.

z Any export of these products, or devices or systems containing them, may require an export license or other official

approval under the law and regulati ons of the country of export pertaini ng to customs and tariffs, currency exchange,

or strategic materials.

z AKM products are neither intended nor authorized for use as critical componentsNote1) in any safety, life support, or

other hazard related device or systemNote2), and AKM assumes no responsibility for such use, except for the use

approved with the express written consent by Repr esentative Director of AKM. As used h ere:

Note1) A critical com ponent is one whose failure to function or perform m ay reasonably be expected to resul t,

whether directly or indirectly, i n the loss of the safety or effect iveness of the device or system containi ng it, and

which must therefore meet very high standards of performance and reliability.

Note2) A hazard related device or system is one designed or intended for life support or ma intenance of safety

or for applications in medicine, aerospace, nuclear energy, or other fields, in which its failure to function or

perform may reasonably be expected to result in loss of life or in significant injury or damage to person or

property.

z It is the responsibility of the buyer or distributor of AKM products, who distributes, disposes of, or otherwise places

the product with a third party, to notify such third party in advance of the above content and conditions, and the buyer

or distributor agrees to assume any and all responsibility and liability for and hold AKM harmless from any and all

claims arising from the use of said product in the absence of such notification.