This is information on a product in full production.
October 2014 DocID023043 Rev 7 1/26
STPA001
4 x 50 W MOSFET quad bridge power amplifier
Datasheet - production data
Features
Multipower BCD technology
High output power capability:
4 x 50 W/4 Ω Max.
4 x 28 W/4 Ω @ 14.4 V, 1 kHz, 10 %
4 x 72 W/2 Ω Max.
MOSFET output power stage
2 Ω driving capability
Hi-Fi class distortion
Low output noise
High immunity to RF noise injection
Standby function
Mute function
Automute at min. supply voltage detection
Low external component count
Internally fixed gain (26 dB)
Protections:
Output short circuit to GND, to Vs, across
the load
Very inductive loads
Overrating chip temperature with soft
thermal limiter
Output DC offset detection
Load dump
Fortuitous open GND
Reversed battery
ESD
Capable to operate down to 6 V (e.g.
“Startstop”)
Description
The STPA001 is a breakthrough MOSFET
technology class AB audio power amplifier
designed for high power car radio. The fully
complementary P-Channel/N-Channel output
structure allows a rail to rail output voltage swing
which, combined with high output current and
minimized saturation losses sets new power
references in the car-radio field, with unparalleled
distortion performances.
The STPA001 can operate down to 6 V and this
makes the IC compliant to the most recent OEM
specifications for low voltage operation (so called
'start-stop' battery profile during engine stop),
helping car manufacturers to reduce the overall
emissions and thus contributing to environment
protection.
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Flexiwatt27 (Vertical)
Flexiwatt25 (Vertical) Flexiwatt25 (Horizontal)
Flexiwatt27 (Horizontal)
Table 1. Device summary
Order code Package Packing
STPA001 Flexiwatt25 (Vertical) Tube
STPA001H Flexiwatt25 (Horizontal) Tube
STPA001A Flexiwatt27 (Vertical) Tube
STPA001AH Flexiwatt27 (Horizontal) Tube
www.st.com
Contents STPA001
2/26 DocID023043 Rev 7
Contents
1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1 Block diagram and application circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1 Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Pin functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3 Electrical specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Electrical characteristics curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.2 Battery variations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.2.1 Low voltage operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.2.2 Cranks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.2.3 Advanced battery management (hybrid vehicles) . . . . . . . . . . . . . . . . . 17
4.3 Protections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.1 Short circuits and open circuit operation . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.2 Over-voltage and load dump protection . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.3.3 Thermal protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.4 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.4.1 DC offset detection (OD pin) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.4.2 Clipping detection and diagnostics (CD-DIAG pin) . . . . . . . . . . . . . . . . 19
4.5 Heat sink definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5 Package information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
DocID023043 Rev 7 3/26
STPA001 List of tables
3
List of tables
Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table 2. Pin functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 3. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 4. Thermal data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 5. Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 6. Document revision history. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
List of figures STPA001
4/26 DocID023043 Rev 7
List of figures
Figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 2. Application circuit (STPA001) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 3. Application circuit (STPA001A & STPA001H) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 4. Pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 5. Quiescent current vs. supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 6. Output power vs. supply voltage (4 Ω) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 7. Output power vs. supply voltage (2 Ω) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 8. Distortion vs. output power (4 Ω) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 9. Distortion vs. frequency (4 Ω) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 10. Distortion vs. output power (4 Ω, Vs = 6 V). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 11. Distortion vs. output power (2 Ω) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 12. Distortion vs. frequency (2 Ω) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 13. Distortion vs. output power (2 Ω, Vs = 6 V). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 14. Supply voltage rejection vs. frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 15. Crosstalk vs. frequency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 16. Total power dissipation & efficiency vs. Po (4 Ω, Sine) . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 17. Power dissipation vs. average output power (4 Ω, audio program simulation). . . . . . . . . . 14
Figure 18. Power dissipation vs. average output power (2 Ω, audio program simulation). . . . . . . . . . 14
Figure 19. ITU R-ARM frequency response, weighting filter for transient pop. . . . . . . . . . . . . . . . . . . 14
Figure 20. SVR charge diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 21. Battery cranking curve example 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Figure 22. Battery cranking curve example 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Figure 23. Upwards fast battery transitions diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 24. Load dump protection diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Figure 25. Thermal protection diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 26. Audio section waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 27. Flexiwatt27 (vertical) mechanical data and package dimensions. . . . . . . . . . . . . . . . . . . . 21
Figure 28. Flexiwatt27 (horizontal) mechanical data and package dimensions. . . . . . . . . . . . . . . . . . 22
Figure 29. Flexiwatt25 vertical mechanical data and package dimensions . . . . . . . . . . . . . . . . . . . . . 23
Figure 30. Flexiwatt25 (horizontal) mechanical data and package dimensions. . . . . . . . . . . . . . . . . . 24
DocID023043 Rev 7 5/26
STPA001 Overview
25
1 Overview
The STPA001 is a complementary quad audio power amplifier. It is available in three
different packages, Flexiwatt25 (vertical), Flexiwatt25 (horizontal) and Flexiwatt27. It
embeds four independent amplifiers working in class AB, a standby and a mute pin, a
clipping detector and diagnostics output and, only for the Flexiwatt27 package, an offset
detector pin. The amplifier is fully operational down to a battery voltage of 6 V, without
producing pop noise and continuing to play during battery transitions.
The STPA001 can drive 2 Ω loads and has a very high immunity to disturbs without need of
external components or compensation. It is protected against any kind of short or open
circuit, over-voltage and over-temperature.
1.1 Block diagram and application circuit
Figure 1. Block diagram
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Overview STPA001
6/26 DocID023043 Rev 7
Figure 2. Application circuit (STPA001)
Figure 3. Application circuit (STPA001A & STPA001H)
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DocID023043 Rev 7 7/26
STPA001 Pin description
25
2 Pin description
2.1 Pin connection
Figure 4. Pin connection (top view)
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Pin description STPA001
8/26 DocID023043 Rev 7
2.2 Pin functions
Table 2. Pin functions
Pin number
FW27
Pin number
FW25 Pin name Description
11 TAB-
2 25 OD Offset detector output
3 2 PW-GND2 Channel 2, output power ground
4 3 OUT2- Channel 2, negative output
5 4 ST-BY Stand-by
6 5 OUT2+ Channel 2, positive output
7 6 VCC Supply voltage
8 7 OUT1- Channel 1, negative output
9 8 PW-GND1 Channel 1, output power ground
10 9 OUT1+ Channel 1, positive output
11 10 SVR Supply voltage rejection pin
12 11 IN1 Channel 1, input
13 12 IN2 Channel 2, input
14 13 S-GND Signal ground
15 14 IN4 Channel 4, input
16 15 IN3 Channel 3, input
17 16 AC-GND AC ground
18 17 OUT3+ Channel 3, positive output
19 18 PW-GND3 Channel 3, output power ground
20 19 OUT3- Channel 3, negative output
21 20 VCC Supply voltage
22 21 OUT4+ Channel 4, positive output
23 22 MUTE Mute pin
24 23 OUT4- Channel 4, negative output
25 24 PW-GND4 Channel 4, output power ground
26 n.a CD-DIAG Clipping detector and diagnostics output
27 n.a TAB -
DocID023043 Rev 7 9/26
STPA001 Electrical specifications
25
3 Electrical specifications
3.1 Absolute maximum ratings
3.2 Thermal data
Table 3. Absolute maximum ratings
Symbol Parameter Value Unit
VSOperating supply voltage 18 V
VS (DC) DC supply voltage 28 V
VS (pk) Peak supply voltage (for t = 50 ms) 50 V
IO
Output peak current
Non repetitive (t = 100 μs)
Repetitive (duty cycle 10 % at f = 10 Hz)
10
9
A
A
Ptot Power dissipation Tcase = 70 °C 85 W
TjJunction temperature 150 °C
Tstg Storage temperature -55 to 150 °C
GNDmax Ground pin voltage -0.3 to 0.3 V
Vin max Input pin max voltage -0.3 to 8 V
VSB max ST-BY pin max voltage -0.3 to Vs (pk) V
Vmute max Mute pin max voltage -0.3 to 6 V
Table 4. Thermal data
Symbol Parameter Value Unit
Rth j-case Thermal resistance junction-to-case Max 1 °C/W
Electrical specifications STPA001
10/26 DocID023043 Rev 7
3.3 Electrical characteristics
Refer to the test and application diagram, VS = 14.4 V; RL = 4 Ω; R
g
= 600 Ω; f = 1 kHz;
Tamb = 25 °C; unless otherwise specified.
Table 5. Electrical characteristics
Symbol Parameter Test condition Min. Typ. Max. Unit
General characteristics
VSSupply voltage range - 6 - 18 V
I
q1
Quiescent current R
L
= 100 200 300 mA
V
OS
Output offset voltage Play mode / Mute mode -90 - +90 mV
dV
OS
During mute ON/OFF output offset
voltage
ITU R-ARM weighted
-10 - +10 mV
During standby ON/OFF output
offset voltage -15 - +15 mV
R
i
Input impedance - 40 55 70 kΩ
I
SB
Standby current consumption
V
St-b
y = 1.2 V - - 20 μA
V
St-b
y = 0 - - 10 μA
Audio performances
P
o
Output power
THD = 10 %
THD = 1 %
26
20
28
22
-
-
W
W
THD = 10 %, 2 Ω
THD = 1 %, 2 Ω
43
34
48
38
-
-
W
W
P
o max.
Max. output power
Square wave input (2 Vrms)
R
L
= 4 Ω
R
L
= 2 Ω
V
S
= 15.2 V; R
L
= 4 Ω
41
68
46
45
75
50
-
-
-
W
W
W
THD Distortion P
o
= 4 W - 0.007 0.05 %
G
v
Voltage gain - 25 26 27 dB
dG
v
Channel gain unbalance - -1 - +1 dB
e
No
Output Noise "A" Weighted
Bw = 20 Hz to 20 kHz
-
-
35
50
-
100
μV
μV
SVR Supply voltage rejection f = 100 Hz; V
r
= 1 Vrms 50 70 - dB
f
ch
High cut-off frequency P
O
= 0.5 W 100 300 - kHz
C
T
Cross talk f = 1 kHz P
O
= 4 W
f = 10 kHz P
O
= 4 W
60
-
75
60
-
-
dB
dB
AMMute attenuation P
Oref
= 4 W 80 90 - dB
Control pin characteristics
I
pin5
Standby pin current V
St-b
y = 1.2 V to 2.6 V - - 1 μA
V
SB out
Standby out threshold voltage (Amp: ON) 2.6 - - V
DocID023043 Rev 7 11/26
STPA001 Electrical specifications
25
V
SB in
Standby in threshold voltage (Amp: OFF) - - 1.2 V
V
M out
Mute out threshold voltage (Amp: Play) 2.6 - - V
V
M in
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V
AM in
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Att 80 dB; P
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(Sourced current) 5812μA
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V
OFF
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V
OFF_SAT
Off detector saturation voltage Vo > ±3 V, I
off Det
= 1 mA
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V
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Clipping detector
CD
LK
Clip detector high leakage current Cd off - 0 1 μA
CD
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CD
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Clip detector THD level VCC > 6.5 V - 1 - %
Table 5. Electrical characteristics (continued)
Symbol Parameter Test condition Min. Typ. Max. Unit
Electrical specifications STPA001
12/26 DocID023043 Rev 7
3.4 Electrical characteristics curves
Figure 5. Quiescent current vs. supply voltage Figure 6. Output power vs. supply voltage (4 Ω)
Figure 7. Output power vs. supply voltage (2 Ω) Figure 8. Distortion vs. output power (4 Ω)
Figure 9. Distortion vs. frequency (4 Ω) Figure 10. Distortion vs. output power
(4 Ω, Vs = 6 V)
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STPA001 Electrical specifications
25
Figure 11. Distortion vs. output power (2 Ω) Figure 12. Distortion vs. frequency (2 Ω)
Figure 13. Distortion vs. output power (2 Ω,
Vs = 6 V)
Figure 14. Supply voltage rejection vs.
frequency
Figure 15. Crosstalk vs. frequency Figure 16. Total power dissipation & efficiency
vs. Po (4 Ω, Sine)
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Electrical specifications STPA001
14/26 DocID023043 Rev 7
Figure 17. Power dissipation vs. average output
power (4 Ω, audio program simulation)
Figure 18. Power dissipation vs. average output
power (2 Ω, audio program simulation)
Figure 19. ITU R-ARM frequency response,
weighting filter for transient pop
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DocID023043 Rev 7 15/26
STPA001 General information
25
4 General information
4.1 Operation
The STPA001's inputs are ground-compatible. If the standard value for the input capacitors
(0.22 μF) is adopted, the low frequency cut-off will amount to 16 Hz. The input capacitors
should be 1/4 of the capacitor connected to AC-GND pin for optimum pop performances
(see Figure 2: Application circuit (STPA001)).
Standby and mute pins are both CMOS compatible.
RC cells at both mute and stand-by pins have always to be used in order to smooth the
transitions for preventing any audible transient noise.
In case muting and stand-by functions are not used, they could steadily be connected to VS,
but a 470 kΩ resistance should be present between the power supply and the pins.
The capacitance on SVR sets the start-up and shut-down times and helps to have pop-noise
free transitions. Its minimum recommended value is 10 μF. However, to have a fast start-up
time, the internal resistor on SVR pin, used to set the time constant, is reduced from 50 kΩ
to 3 kΩ till voltage on SVR reaches VCC/4 -2VBE and then released. In this way the
capacitor on SVR is charged very quickly to VCC/4, as shown in the following figure.
The time constant to be assigned to the standby pin in order to obtain a virtually pop-free
transition has to be slower than 2.5 V/ms.
Figure 20. SVR charge diagram
SVR pin accomplishes multiple functions:
it is used as a reference voltage for input pins (VCC/4)
the capacitor connected to SVR helps the supply voltage ripple rejection
it is used as a reference to generate the half supply voltage for the output
When the amplifier goes in standby mode or goes out from this condition, it is suggested to
put the amplifier in mute to ensure the absence of audible noise. Then the stand-by pin can
be set to the appropriate value (ground or > 2.6 V) and the capacitance on SVR pin is
discharged or charged consequently.
4.2 Battery variations
4.2.1 Low voltage operation
The most recent OEM specifications are require automatic stop of car engine at traffic lights,
in order to reduce emissions of polluting substances. The STPA001, thanks to its innovating
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General information STPA001
16/26 DocID023043 Rev 7
design, allows a continuous operation when battery falls down. At 6 V it is still fully
operational, only the maximum output power is reduced accordingly to the available voltage
supply.
If the battery voltage drops below the minimum operating voltage of 6V the amplifier is fast
muted, the capacitor on SVR is discharged and the amplifier restarts when the battery
voltage returns to the correct voltage.
4.2.2 Cranks
STPA001 can sustain worst case cranks from 16 V to 6 V, continuing to play and without
producing any pop noise.
Examples of battery cranking curves are shown below, indicating the shape and duration of
allowed battery transitions.
Figure 21. Battery cranking curve example 1
V1 = 16 V; V2 = 6 V; V3 = 7 V; V4 = 8 V
t1 = 2 ms; t2 = 50 ms; t3 = 5 ms; t4 = 300 ms; t5 =10 ms; t6 = 1 s; t7 = 2 ms
Figure 22. Battery cranking curve example 2
V1 = 16 V; V2 = 6 V; V3 = 7 V
t1 = 2 ms; t2 = 5 ms; t3 = 15 ms; t5 = 1 s; t6 = 50 ms
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STPA001 General information
25
4.2.3 Advanced battery management (hybrid vehicles)
In addition to compatibility with low Vbatt, the STPA001 is able to sustain upwards fast
battery transitions without causing unwanted audible effects, like pop noise, and without any
sound interruption thanks to the innovative circuit topology. In fact, in hybrid vehicles, the
engine ignition causes a fast increase of battery voltage which can reach 16 V in less than
10 ms.
Figure 23. Upwards fast battery transitions diagram
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General information STPA001
18/26 DocID023043 Rev 7
4.3 Protections
4.3.1 Short circuits and open circuit operation
When the IC detects a short circuit to ground, to Vs or across the load, the output of the
amplifier is put in three-state (high impedance condition). The power stage remains in this
condition until the short is removed.
In case of short circuit to ground or Vcc, the amplifier exits from the three-state condition
only when the output returns inside the limits imposed by an internal voltage comparator.
When a short across the load is present, the power stage sees an over-current and is
brought in protection mode for 100 μs. After this time, if the short circuit condition is removed
the amplifier returns to play, otherwise the high impedance state is maintained and the
check is repeated every 100 μs.
Disconnection of load (open load condition) doesn't damage the amplifier, which continues
to play.
4.3.2 Over-voltage and load dump protection
When the battery voltage is higher than 19 V, the amplifier is switched to a high impedance
state. It stops to playing till the supply voltage returns in the permitted range.
The amplifier is protected against load dump surges having amplitude as high as 50 V and a
rising time lower than 5 ms (see Figure 24).
Figure 24. Load dump protection diagram
4.3.3 Thermal protection
If the junction temperature of the IC reaches Tj = 150 °C, a smooth mute is applied to reduce
output power and limit power dissipation. If this is not enough and the junction temperature
continues to increase, the amplifier is switched off when reaches the maximum temperature
of 170 °C.
Figure 25. Thermal protection diagram
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DocID023043 Rev 7 19/26
STPA001 General information
25
4.4 Warnings
4.4.1 DC offset detection (OD pin)
The STPA001 integrates a DC offset detector to avoid that an anomalous input DC offset is
multiplied by the amplifier gain producing a dangerous large offset at the output. In fact an
output offset may lead to speakers damage for overheating. The detector works with the
amplifier un-muted and no signal at the inputs.
When the differential output voltage is out of a window comparator with thresholds ± 2V
(typ), the OD pin is pulled down.
4.4.2 Clipping detection and diagnostics (CD-DIAG pin)
When clipping occurs, the output signal is distorted. If the signal distortion on one of the
output channels exceeds 1%, the CD-DIAG pin is pulled down. This information can be sent
to an audio processor in order to reduce the input signal of the amplifier and reduce the
clipping. Thanks to a particular internal circuitry, the clip detector is always functional till
6.5 V.
A short to ground and short to Vcc is pointed out by CD-DIAG. This pin is pulled down to 0 V
till these shorts are present to inform the user a protection occurred.
CD-DIAG acts also as thermal warning. In fact every time Tj exceeds 140 °C, it is pulled
down to notify this occurrence.
Figure 26. Audio section waveforms
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4.5 Heat sink definition
Assuming we have a maximum dissipated power of 26 W (e.g. in the worst case situation of
frequent clipping occurrence), considering Tj max is 150°C and assuming ambient
temperature is 70 °C, the available temperature gap for a correct dissipation is 80 °C.
This means the thermal resistance of the system RTh has to be 80 °C/26 W = 3 °C/W.
The junction to case thermal resistance is 1 °C/W. So the heat sink thermal resistance
should be approximately 2 °C/W. This would avoid any thermal shutdown occurrence even
after long-term and full-volume operation.
DocID023043 Rev 7 21/26
STPA001 Package information
25
5 Package information
In order to meet environmental requirements, ST offers these devices in different grades of
ECOPACK® packages, depending on their level of environmental compliance. ECOPACK®
specifications, grade definitions and product status are available at: www.st.com.
ECOPACK® is an ST trademark.
Figure 27. Flexiwatt27 (vertical) mechanical data and package dimensions
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Figure 28. Flexiwatt27 (horizontal) mechanical data and package dimensions
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STPA001 Package information
25
Figure 29. Flexiwatt25 vertical mechanical data and package dimensions
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Figure 30. Flexiwatt25 (horizontal) mechanical data and package dimensions
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DocID023043 Rev 7 25/26
STPA001 Revision history
25
6 Revision history
Table 6. Document revision history
Date Revision Changes
03-Apr-2012 1 Initial release.
10-Sep-2012 2 Updated Table 3: Absolute maximum ratings on page 9.
14-Nov-2012 3
Updated:
Features on page 1;
Section 1.1: Block diagram and application circuit;
Section 3.3: Electrical characteristics;
Section 4.4.2: Clipping detection and diagnostics (CD-DIAG pin) on
page 19;
Added Section 3.4: Electrical characteristics curves.
05-Sep-2013 4 Updated Figure 17 & 18.
18-Sep-2013 5 Updated Disclaimer.
05-Sep-2014 6
Updated Table 1: Device summary on page 1.
Added Figure 30: Flexiwatt25 (horizontal) mechanical data and
package dimensions on page 24.
27-Oct-2014 7
Updated Table 1: Device summary on page 1.
Added Figure 28: Flexiwatt27 (horizontal) mechanical data and
package dimensions on page 22
STPA001
26/26 DocID023043 Rev 7
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