driving current under fault)
ST-BY IN Threshold Voltage1.5V
ST-BY OUT Threshold Voltage3.5V
MUTE Attenuation80dB
MUTE IN Threshold Voltage1.5V
MUTE OUT Threshold Voltage3.5V
dB
dB
3/10
TDA7372A
TEST AND APPLICATION CIRCUIT
R2
10µF
C13
Figure1: P.C. Boardand componentslayout of the Test and ApplicationCircuit(1:1 scale)
4/10
TDA7372A
Figure 2: Quiescent Drain Current vs. Supply
Voltage
Figure4: Output Power vs SupplyVoltage
Figure3: OutputPower vs. SupplyVoltage
Figure 5: Output power vs. Frequency vs.C
Value
OUT
Figure6: Distortion vs. Output Power
Figure7: Distortionvs. Output Power
5/10
TDA7372A
Figure8: Distortion vs. Frequency
Figure10: Cross-Talkvs. Frequency
Figure9: Distortionvs. Frequency
Figure11: SupplyVoltageRejectionvs.Frequency
Figure 12: TotalPower Dissipation and Efficiency
vs. OutputPower
P
(W)
tot
P
tot
6/10
Figure13: Total Power Dissipation and Efficiency
vs. Output Power
P
(W)
tot
P
tot
Figure14: TDA7313+ 7372 Application Circuit
TDA7372A
10µF
7/10
TDA7372A
FUNCTIONAL DESCRIPTION
FunctionDescription
The TDA7372A is a quad channel single package audio power amplifier intended to reduce the
GENERAL
OUTPUT STAGE
ST-BY
MUTE
THERMAL
PROTECTION
BUILT-IN SHORT
CIRCUIT
PROTECTION
mismatch in the electrical characteristics among the four different channels and to consistently
drop the external component count. It contains four non inverting stages capable to operate
down to 20dB gain so minimizing the output noise and optimizing SVR and distortion.
The output stage is a single ended type suitable to drive 4Ω loads. It consists of a class AB fully
complementary PNP/NPN stages short circuit protected.
A rail to rail output swing is achieved without need of boostrap capacitors. Moreover, the
external compensation is not necessary.
The device features a St-BY function which shuts down the internal bias generators when the
ST-BY input is low. In ST-BY mode the amplifier sinks a small current (in the range of few µAs).
When the St-BYpin is high the IC becomes fully operational.
A mute function is also provided. This reduces the gain of the input stage to a level effectively
eliminating any audio input influence on the output stage when the mute line is low. When the
mute line is high the normal input path is restored.
The device goes automatically into mute state when the supply voltage goes below the
minimum allowable value. This prevents pop noises whenever the battery voltage drops below
a fixed threshold. Whenthe supply voltage rises to it nominal value the device recoversthe play
condition with a delay fixed by the C
SVR
The Thermal protection principle involves two different steps
a) Soft thermal limitation
b) Shutdown
As long as the junction temperature remains below a preset threshold, the I.C. will deliver the
full power. Once the threshold has been reached, the device automatically goes into mute
status. The play to mute transition is internally controlled so producing a soft muting without
unpleasant effect. Supposing the junction temperature does not reduce to safe levels, a
complete shutdown will occur.
A built-in protection circuit assures reliable and safe operation in presence of:
- AC short circuit to GND
- DC short circuit to GND and to V
duringpower-on phase
S
The DC short protector acts in a way to avoid that the device is being turned on (by ST-BY)
when a DC short is present from OUT to GND or OUT to V
to introduce a proper delay on the st-by pin (expecially when it is drivenby V
Moreover, as the involved circuitry is normally disabled when a current higher than 5mA is fed
into the st-by pin, it is important, in order not to disable it, to have the external current source
driving the pin itself limited to 5mA. (figure 1 is shows the relevant waveforms).
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsibility for the
consequences of use of such informationnor for any infringement of patents or otherrights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of SGS-THOMSON Microelectronics.
1995 SGS-THOMSON Microelectronics - All RightsReserved
MULTIWATT is a Registered Trademark of the SGS-THOMSON Microelectronics
SGS-THOMSON Microelectronics GROUP OF COMPANIES
Australia - Brazil- France -Germany - Hong Kong - Italy - Japan - Korea -Malaysia -Malta - Morocco - The Netherlands - Singapore-
Spain - Sweden - Switzerland - Taiwan - Thaliand - United Kingdom - U.S.A.
10/10
Loading...
+ hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.