#amplifier circuit

The above circuit uses a simple NPN Transistor Q1 2N4401 and powered by a 12v Supply. The resistor values R1,R2,R3,R4 and capacitor values C1,C2 plays major role in amplification of input signals. So fixing these values requires some simple math to meet our amplification requirements. First we need to fix the value of Collector resistor R3 based on the desired collector current and voltage.  Capacitor C2 of 1uF was added to remove the DC offset in the input signal and keep our circuit stable. 

21W Class AB Audio Amplifier

This is the circuit design of 21W class AB audio amplifier uses power transistors as the main part. It is a simple design, and simple to set up. Set the 10k trimmer to about half way and the 470 ohm trimmer to 0 resistance. Power up and set the quiescent current to 30mA by trimming the 470 ohm trimmer. Once done, measure the offset voltage. Trim the 10k so that between -30 and 30mV is measured.…

This is simple portable audio amplifier circuit. This circuit built based on IC TEA2025 which is a monolithic integrated audio amplifier in a 16-pin plastic dual in line package manufactured by UTC. Circuit has Internal Thermal Protector. It is designed for portable cassette players, mp3 players and radios. You can also use it as your smartphone or PC audio amplifier. This circuit require 9V…

2 Watt Mini Audio Amplifier

2 Watt Mini Audio Amplifier Circuit Diagram

This is the circuit diagram of 2 Watt mini audio amplifier. This circuit is inexpensive, easy and quite simple. This is general audio amplifier which can be used for computer, CD player or other devices which have headphone output.

The circuit was deliberately designed using no ICs and in a rather old-fashioned manner in order to obtain good harmonic…