LM3876 is a high performance audio power amplifier IC from National Semiconductors. The LM3876 can deliver 50watts of output power into an 8 ohm loudspeaker. LM3876 has excellent signal to noise ratio and has wide supply voltage range. Other features of LM3876 are output to ground short circuit protection, input mute function, and output over voltage protection, etc. Applications of LM3876 are component stereo, compact stereo, surround systems, self powered speakers, etc. Circuit diagram : 50W audio amplifier Circuit Diagram The 50 watt audio amplifier circuit shown below is designed based on the application diagram from the data sheet of LM3876. Some modifications are made on the original circuit for improving the performance. The bipolar electrolytic capacitor C7 is the input DC decoupling capacitor. R4 is the input resistance. R2 & R1 and bipolar electrolytic capacitor C5 forms a feedback circuit. C2, C1 are filter/by-pass capacitors for the positive supply rail. C4 &...