Datasheet TDA7375AV, TDA7375AH Datasheet (SGS Thomson Microelectronics)



TDA7375A

2 x 37WDUAL/QUAD POWER AMPLIFIER FOR CAR RADIO

HIGHOUTPUTPOWER CAPABILITY
2

x 43W/4Ω MAX

2

x 37W/4

2

x 26W/4

x 7W/4Ω @14.4V,1KHz,10%

4
4

x 12W/2Ω @14.4V, 1KHz,10%

MINIMUM EXTERNAL COMPONENTS
COUNT:
– NOBOOTSTRAPCAPACITORS
– NOBOUCHEROTCELLS
– INTERNALLY FIXEDGAIN (26dBBTL)

ST-BYFUNCTION(CMOSCOMPATIBLE)
NO AUDIBLE POP DURING ST-BY OPERA-

TIONS
DIAGNOSTICFACILITIES

– CLIPDETECTOR
– OUTTO GND SHORT
– OUTTO V
– SOFTSHORTAT TURN-ON
– THERMAL SHUTDOWNPROXIMITY

Protections:

OUPUTAC/DC SHORT CIRCUIT
– TOGND

EIAJ

Ω

@14.4V,1KHz,10%

Ω

SHORT

S

Multiwatt15 V

ORDERING NUMBERS: TDA7375AV

–TOV

S

TDA7375AH

– ACROSS THE LOAD
SOFTSHORT AT TURN-ON
OVERRATING CHIP TEMPERATURE WITH

SOFTTHERMAL LIMITER
LOADDUMP VOLTAGESURGE
VERYINDUCTIVELOADS
FORTUITOUSOPEN GND
REVERSEDBATTERY
ESD

BLOCK DIAGRAM

October 1998

1/14

TDA7375A

DESCRIPTION

The TDA7375A is a new technology class AB car
radio amplifier able to work either in DUAL
BRIDGEor QUADSINGLE ENDED configuration.
The exclusive fully complementarystructureof the
output stage and the internally fixed gain guaran-

tee the highest power performances with ex­tremely reduced component count. The on board
clip detector simplifies gain compression opera­tion. The fault diagnostic makes it possible to de­tect mistakes during car radio set assembly and
wiring in the car.

GENERALSTRUCTURE

ABSOLUTEMAXIMUM RATINGS

Symbol Parameter Value Unit

V

op

V

V

peak

I

O

I

O

P

tot

T

stg,Tj

Operating Supply Voltage 18 V
DC Supply Voltage 28 V

S

Peak Supply Voltage(for t = 50ms) 40 V
Output Peak Current (notrepitive t = 100µs) 4.5 A
Output Peak Current (repetitivef > 10Hz) 3.5 A
Power Dissipation T
Storage and Junction Temperature -40 to 150 °C

=85°C36W

case

THERMAL DATA

Symbol Description Value Unit

R

th j-case

Thermal Resistance Junction-case Max 1.8 °C/W

PIN CONNECTION (Topview)

2/14

TDA7375A

ELECTRICALCHARACTERISTICS (Referto the testcircuit, VS=14.4V;RL=4Ω; f =1KHz;

T

=25°C,unless otherwise specified

amb

Symbol Parameter Test Condition Min. Typ. Max. Unit

V

S

I

d

V

OS

P

O

P

O max

P

O EIAJ

THD Distortion R

CT Cross Talk f = 1KHz Single Ended

R

IN

G

V

G

V

E

IN

SVR Supply Voltage Rejection R

A

SB

I

SB

V

SB

V

SB

I

pin7

I

cd off

I

cd on

V

sat pin10

(*) See built-in S/C protection description
(**) Pin 10 Pulled-up to 5V with 10KΩ;R
(***) Saturatedsquare waveoutput.

Supply Voltage Range 8 18 V
Total Quiescent DrainCurrent RL= ∞ 150 mA
Output Offset Voltage 150 mV
Output Power THD = 10%; RL=4

Bridge
Single Ended
Single Ended, R

Ω

23

6.5

=2

Ω

L

26

7

12
Max. Output Power (***) VS = 14.4V,Bridge 37 43 W
EIAJ Output Power (***) VS= 13.7V, Bridge 33 37 W

=4Ω

L

Single Ended, P
Bridge, P

O

= 0.1 to 4W

O

= 0.1 to10W

0.02

0.03 0.3
70

f = 10KHzSingle Ended
f = 1KHz Bridge

f = 10KHzBridge

Input Impedance Single Ended

Bridge

Voltage Gain Single Ended

Bridge

55

20
10

19
25

60

60
30

15
20

26

21

27
Voltage Gain Match 0.5 dB
Input Noise Voltage Rg= 0; ”A”weighted, S.E.

Non Inverting Channels
Inverting Channels

2
5

Bridge
Rg = 0;22Hz to 22KHz 3.5 µV

= 0; f = 300Hz 50 dB

g

Stand-by Attenuation PO=1W 80 90 dB
ST-BY Current Consumption V

= 0 to1.5V 100

ST-BY

ST-BY In ThresholdVoltage 1.5 V
ST-BY Out ThresholdVoltage 3.5 V
ST-BY Pin Current Play ModeV

Max Driving Current Under

=5V 50 µA

pin7

5mA

Fault (*)

Clipping Detector

d = 1%(**) 90

Output Average Current
Clipping Detector

d = 5%(**) 160 µA

Output Average Current
Voltage Saturation on pin10 Sink Currentat Pin 10= 1mA 0.7 V

=4Ω

L

W
W
W

%
%

dB
dB

dB
dB

K
KΩ

dB
dB

µV
µV

µ

µ

Ω

A

A

3/14

TDA7375A

STANDARD TEST AND APPLICATION CIRCUIT
Figure 1: Quad Stereo

Note:

The output decoupling capaci t or s
(C9,C10,C11,C12)could bereducedto
1000µFifthe2Ωoperation is not
required.

Figure 2: Double Bridge

ST-BY

IN L

ST-BY

IN FR 5

IN RR 11

10K R1

IN FL

C1 0.22µF

C2 0.22µF

C4 0.22µF

C3 0.22µF

C8 47µF

10K R1

C5

10µF

C1 0.47µF

C2 0.47µF

C8 47µF

C7

10µF

7

13

4

12IN RL

6

89 10

3

DIAGNOSTICS

C4

100nF

13

7

4

3

1

5

12IN R
11

6

2

15

14

89 10

DIAGNOSTICS

C6

100nF

1

2

15

14

C10 2200µF

C9 2200µF

C11 2200µF

C12 2200µF

D94AU063A

OUT L

OUT R

D94AU064A

V

S

C5

1000µF

V

C3

1000µF

OUT FL

OUT FR

OUT RL

OUT RR

S

Figure 3: Stereo/Bridge

IN BRIDGE 12

4/14

ST-BY

IN L

IN L

10K

0.22µF

0.22µF

0.47µF

47µF

10µF

13

7

4

3

5

11
6

89 10

DIAGNOSTICS

15

14

1

2

2200µF

2200µF

D94AU065A

1000µF100nF

OUT L

OUT R

OUT

BRIDGE

V

S

Figure 4: P.C. Board and ComponentLayout of the fig.1(1:1 scale).

TDA7375A

Figure 5: P.C. Board and ComponentLayout of the fig.2(1:1 scale).

5/14

TDA7375A

Figure 6: QuiescentDrain Currentvs. Supply

Voltage(Single Ended and Bridge).

Figure 8: Output Power vs. Supply Voltage

Figure7: QuiescentOutputVoltage vs.Supply

Voltage (SingleEnded andBridge).

Figure9: OutputPower vs. Supply Voltage

Figure 10: OutputPowervs. SupplyVoltage

6/14

Figure11: Distortionvs. Output Power

TDA7375A

Figure 12: Distortionvs. OutputPower

Figure 14: Cross-talkvs. Frequency

Figure13: Distortionvs. Output Power

Figure15: SupplyVoltage Rejection vs. Fre-

quency

Figure16:SupplyVoltageRejectionvs.Frequency

Figure17: Stand-byAttenuationvs. Threshold

Voltage

7/14

TDA7375A

Figure 18: TotalPowerDissipationand Effi-

ciency vs. OutputPower

Figure19: TotalPower Dissipation and Effi-

ciencyvs. OutputPower.

8/14

TDA7375A

High ApplicationFlexibility

The availability of 4 independentchannels makes
it possible to accomplish several kinds of applica­tions ranging from 4 speakers stereo (F/R) to 2
speakersbridge solutions.
In case of working in single ended conditions the
polarity of the speakers driven by the inverting
amplifier must be reversedrespect to those driven
by noninverting channels.
This is to avoid phase inconveniences causing
sound alterations especially during the reproduc­tion of low frequencies.

Easy SingleEnded to BridgeTransition

The change from single ended to bridge configu­rations is made simplyby means of a short circuit
across theinputs, that is no need of furtherexter­nal components.

Gain Internally Fixed to 20dB in Single Ended,
26dB inBridge

Advantagesof thisdesign choice are interms of:

componentsand space saving
output noise, supply voltage rejection and dis-

tortion optimization.

Silent Turn On/Off and Muting/Stand-by Func­tion

The stand-by can be easily activated by means of
a CMOSlevel applied to pin 7 througha RC filter.
Under stand-by condition the device is turned off
completely (supply current = 1µA typ.; output at-
tenuation= 80dBmin.).

Every ON/OFFoperationis virtually pop free.
Furthemore, at turn-on the device staysin muting

condition for a time determined by the value as­signed to theSVR capacitor.
While in muting the device outputs becomes in­sensitive to any kinds of signal that may be pre­sent at the input terminals. In other words every
transient coming from previous stages produces
no unplesantacousticeffectto the speakers.

Need of Bootstrap Capacitors.

The outputswing is limited only by theVCEsat
of the outputtransistors,which arein therange
of 0.3Ω (R

) each.

sat

Classical solutions adopting composite PNP­NPN for the upper output stage have higher
saturationloss onthe topside of the waveform.
This unbalanced saturation causes a signifi­cant power reduction. The only way to recover
power consists of the addition of expensive
bootstrapcapacitors.

Absolute Stability Without Any External
Compensation.

Referring to the circuit of fig. 20 the gain
V

Out/VIn

R2/R1. The DC output (V

is greaterthan unity, approximately 1+

/2) is fixed by an

CC

auxiliaryamplifier common to allthe channels.
By controlling the amount of thislocal feedback
it is possibleto force the loop gain (A*β) toless
than unity at frequency for which the phase
shift is 180°. This means that the output buffer
is intrinsically stable and not prone to oscilla­tion.
Most remarkably, the above feature has been
achieved in spite of the very low closed loop
gain of the amplifier.
In contrast, with the classical PNP-NPN stage,
the solution adopted for reducing the gain at
high frequencies makes use of external RC
networks,namely the Boucherotcells.

Figure20: TheNew OutputStage

OUTPUT STAGE

The fully complementary output stage was made
possible by the development of a new compo­nent: the ST exclusive power ICVPNP.

A noveldesign based uponthe connectionshown
in fig. 20 has then allowed the full exploitation of
its possibilities.

The clear advantagesthis new approachhas over
classicaloutput stages areas follows:

Rail-to-Rail Output Voltage Swing With No

BUILT–INSHORT CIRCUIT PROTECTION

Reliable and safe operation, in presence of all
kinds of short circuit involving the outputs is as­sured by BUILT-IN protectors. Additionally to the
AC/DC short circuit to GND, to V

, across the

S

speaker, a SOFT SHORT condition is signalled
out during the TURN-ON PHASE so assuring cor-

9/14

TDA7375A

rect operation for the device itself and for the
loudspeaker.
This particular kind of protection acts in such a
way to avoid the device is turned on (by ST-BY)
when a resistive path (less than 16 ohms) is pre­sent between the output and GND. As the in­volved circuitry is normally disabled when a cur­rent higher than 5mA is flowing into the ST-BY
pin, it is important, in order not to disable it, to
have the external current source driving the ST­BY pin limited to 5mA.

This extrafunction becomes particularly attractive
when, in the single ended configuration, one ca­pacitor is shared between two outputs (see fig.

21).

Figure 21.

Figure22: ClippingDetectionWaveforms

A current sinking at pin10 is provided when acer­tain distortionlevel is reachedat each output.This
function allows gain compression facility when­evertheamplifier is overdriven.

Supposing that the output capacitor C

out

for any
reason is shorted, the loudspeaker will not be
damaged beingthis soft short circuit conditionre­vealed.

DiagnosticFacilities

The TDA7375 is equipped with a diagnostic cir­cuitry able to detectthe followingevents:

Clippingin the output signal
Thermalshutdown
Outputfault:

– shortto GND
– shortto V

S

– softshort at turnon
The information is available across an open
collector output (pin 10) through a currentsink­ing whenthe event is detected

ThermalShutdown

In this case the output 10 will signal the proximity
of the junction temperature to the shutdown
threshold. Typically current sinking at pin 10 will
start ~10°C before the shutdown threshold is
reached.

HANDLING OF THE DIAGNOSTIC INFORMA­Figure23: OutputFault Waveforms(see fig.24)

TDA7375A

10/14

Figure 24: FaultWaveforms

ST-BY PIN

VOLTAGE

2V

OUTPUT

WAVEFORM

TDA7375A

t

OUT TO Vs SHORT

SOFT SHORT

t

OUT TO GND SHORT

Vpin 10

CHECK AT

(TEST PHASE)

CORRECT TURN-ON

TURN-ON

TION

As differentkinds of informationis available at the
same pin (clipping detection, outputfault, thermal
proximity),this signalmust be handledproperly in
order to discriminatethe event.
Figure 25: Waveforms

ST-BY PIN

VOLTAGE

Vs

OUTPUT

WAVEFORM

FAULT DETECTION

t

D94AU149A

SHORT TO GND

OR TO Vs

This could be done taking into account the differ­ent timing of the diagnostic output against differ­ent events.

Normally the clip detector signalling produces a
low levelat out 10 that is shorterreferred to every

t

10

Vpin

WAVEFORM

D94AU150

CLIPPING

SHORT TO GND

OR TO Vs

t

t

THERMAL

PROXIMITY

11/14

TDA7375A

kind of fault detection; based on this assumption
an interface circuitry to differentiate the informa­tion is representedin the following schematic.

Figure 26.

TDA7375A

12/14

TDA7375A

DIM.

MIN. TYP. MAX. MIN. TYP. MAX.

A5
B 2.65 0.104
C 1.6 0.063
D 1 0.039
E 0.49 0.55 0.019 0.022
F 0.66 0.75 0.026 0.030

G 1.02 1.27 1.52 0.040 0.050 0.060
G1 17.53 17.78 18.03 0.690 0.700 0.710
H1 19.6 0.772
H2 20.2 0.795

L 21.9 22.2 22.5 0.862 0.874 0.886

L1 21.7 22.1 22.5 0.854 0.870
L2 17.65 18.1 0.695 0.713
L3 17.25 17.5 17.75 0.679 0.689 0.699
L4 10.3 10.7 10.9 0.406 0.421 0.429
L7 2.65 2.9 0.104 0.114

M 4.25 4.55 4.85 0.167 0.179 0.191

M1 4.63 5.08 5.53 0.182 0.200 0.218

S 1.9 2.6 0.075 0.102
S1 1.9 2.6 0.075 0.102

Dia1 3.65 3.85 0.144 0.152

mm inch

0.197

0.886

OUTLINE AND

MECHANICAL DATA

Multiwatt15 V

13/14

TDA7375A

Information furnished is believed tobe accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publicationsupersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.

The ST logo is a registered trademark of STMicroelectronics

 1998 STMicroelectronics – Printed in Italy – AllRightsReserved

MULTIWATTis aRegistered Trademark of the STMicroelectronics

STMicroelectronics GROUPOF COMPANIES

Australia - Brazil- Canada- China- France - Germany- Italy - Japan - Korea - Malaysia- Malta - Mexico - Morocco - The Netherlands-

Singapore - Spain- Sweden- Switzerland - Taiwan- Thailand - United Kingdom - U.S.A.

http://www.st.com

14/14