The TDA7377 amplifier is a class AB car radio amplifier able to work either in DUAL BRIDGE or QUAD SINGLE ENDED configuration.
With few external components TDA7377 can obtain high audio power performances .
The fault diagnostics makes it possible to detect mistakes during car radio set assembly and wiring in the car.
Main features of Tda7377 audio amplifier electronic project are : reversed battery protection ; short circuit protection ; very inductive loads ; diagnostic facility for clipping , out to gnd short ,out to Vs short
Tda7377 is available with 4 independent channels and can be used in applications with 4 or 2 speaker in single or bridge mode .
The stand-by function can be easily activated by means of a CMOS level applied to pin 7 through a RC filter and the device is turned off completely .
When the stand by functions is use some precautions have to be taken :
pin 7 cannot be directly driven by a voltage source whose current capability is higher than 5mA.

In practical cases a series resistance has always to be inserted, having it the double purpose of limiting the current at pin 7 and to smooth down the stand-by ON/OFF
In any case, a capacitor of at least 100nF from pin 7 to S-GND, with no resistance in between, is necessary to ensure correct turn-on.
The Vs range supported by this audio ic is 8 to 18 volts DC .
The power supply for this test circuit must be around 14.4 volts .
Maximum power ( 2×30 w) for this audio amplifier can be obtained in bridge mode for two channels at 4 ohms load impedance .