Friday, October 19, 2012

Audio Amplifier | LM386

I managed to create a basic audio amplifier using the IC LM386. This post is just a walk through to the creation. LM386 is a very good audio amp, but sometimes it tends to oscillate at low frequencies hence producing a lot of unwanted noise. The basic circuit is

Put this on a bread board. And connect a 3.5mm jack to the other end to input Vin. Use a coupling capacitor of possibly 10uF. The 10K Pot is to control the intensity. Use Vcc of around 9V. I've used a 8ohm speaker.

There is one more mode according to the datasheet. This is supposed to provide a gain of 200.

Sometimes when the gain is more the output is distorted. Be sure to keep that in mind. It is not that powerful. I've always had a hard time handling it, lot of distortions and noise. Check out other modes, experiment, enjoy.


  1. how to connect input signal(audio) to 10k pot. tell me configration.using 3.5mm jack.please tell me how to connect.

  2. Your 3.5 mm jack has 3 leads. One of them is ground, and the other two are left and right signal. If you are trying to amplify both left and right then you will need two amplifiers(Stereo sound). Connect the ground to the circuits ground and one end of the pot. Connect the audio to another end of the pots lead. The middle lead is the input to the amplifier. If you want to use mono, then use the same setup but either add an audio mixer circuit before or if you don't care much about the quality of the design and your audio source, then simply tie both Left and Right signal together and connect it to the POT