The following is a quad amplifier circuit (amplifier with four inputs and four outputs) based TDA7381. This amplifier is designed for car audio system, but you can also use this circuit for other purposes. This circuit has a design very simple and very easy to build.
Top layout / component placement:
The TDA7381 is a class AB audio power amplifier in Flexiwatt25 package designed for car radio applications. You may use the circuit for another application such as mp3 player, computer etc. Thanks to the fully complementary PNP/NPN output configuration the TDA7381 allows a rail to rail output voltage swing with no need of bootstrap capacitors..
The extremely reduced components count allows very compact sets. The on-board clipping detector simplifies gain compression operations. The fault diagnostics makes it possible to detect mistakes during Car- Radio assembly and wiring in the car
Download TDA7831 Datasheet. All information about this circuit is provided in the datasheet.