The Simplest Amplifier Circuit Diagram

I have been looking for a good stereo amplifier circuit diagram for a long time. I am not a HiFi geek, I just wanted to build a simple stereo amplifier that could drive some speakers for my desktop computer.

All the schematic diagrams that I could find seemed to involve lots of hard-to-find components or you had to use it together with a pre-amplifier or some other amplifier stage. It was always something that made me hesitate.

But recently I found this awesome little chip called TEA2025! You only need a few capacitors to make a decent stereo amplifier out of it. It is so simple to build that I put it together on a strip board in just a few hours.

2.5W * 2 Stereo Amplifier

The amplifier circuit diagram shows a 2.5W * 2 stereo amplifier. You can also make a 5W mono amplifier out of it. (Check out the TEA2025 datasheet for more information on that)

On the input side, you should use a dual potentiometer. A dual potmeter allows you to connect both left and right channel on one potentiometer.

This amplifier is great to use together with some speakers to get sound on your desktop computer. I am thinking of putting one in my kitchen and in my bathroom also. Then maybe hook them up to my home network and stream music from a server =) There are many possibilities when you can make such a cheap amplifier.

Amplifier circuit diagram and parts list

Parts list

PART	VALUE	DESCRIPTION
C1	100µF	POLARIZED CAPACITOR
C2	100µF	POLARIZED CAPACITOR
C3	100µF	POLARIZED CAPACITOR
C4	100µF	POLARIZED CAPACITOR
C5	100µF	POLARIZED CAPACITOR
C6	470µF	POLARIZED CAPACITOR
C7	100µF	POLARIZED CAPACITOR
C8	470µF	POLARIZED CAPACITOR
C9	0.22µF	NON-POLARIZED CAPACITOR
C10	0.22µF	NON-POLARIZED CAPACITOR
C11	0.15µF	NON-POLARIZED CAPACITOR
C12	0.15µF	NON-POLARIZED CAPACITOR
TEA2025	TEA2025B	Amplifier chip
SPKR1		4-8 Ohm speaker
SPKR2		4-8 Ohm speaker
R1+R2	10K	DUAL Potentiometer

Total cost of the components (excluding speakers) is about $9. The most expensive component is the potentiometer (about $3-4).

Download Eagle schematics and board layout

Here is the schematics (Eagle), PCB board layout (Eagle) and Gerber files. This board was made to comply with the design rules of Seeed Studio (May 2013).