PAM8403

Small amplifier boards from China

This is a way to make a tiny but powerful and good sounding audio amplifier from a 20 cent amplifier board and small enclosures like the Altoids Mint can and some small and cheap and easy found components.

Parts needed:

PAM8403 Amplifier board. Comes as an amp-only board costing 2 dollars when buying 10 pieces!!
or 1-2 dollars for one board with potentiometer and switch. Both types available from several AliExpress
and eBay sources.

Altoids Tin Can, or any other smallish Tin Can.

Volume potentiometer 10-10K, stereo, audio type (log).

Battery + battery holder. I use one 18650 battery and holder, but three AAA batteries and holder may work as well.

Two pairs of speaker connectors.

One pair of RCA (input) connectors.

One 1-pole toggle switch.

A LED; any colour will work and a 100 Ohm resistor at .25W to .5W.

Possible a piece of stripboard.

Optional: iPod/iPhoine docking station + an extra 2-pole, 2-way switch

Tools needed:

Drilling machine and set of suitable drills, and a reamer if possible.

Pliers

Wire cutter

Soldering iron and solder

Pincers are helpful

Construction

This is waht the small amp boards look like. They are sized like a stamp but are still power enough to produce 2 by 3W.

As the can is very small, I have made a sketch how stuff is to be positioned, but any other design that works OK ... works OK.

With the aid of the outline sketch, holes are drilled for connectors, potentiometer and LED.

The battery holder has a hole for a screw, but I used doublesided tape.
Get everytning into place but be aware that the speaker connectors may be too long for the box or even be so long that they short to the metal can's bottom.
The LED is monted on a small stripboard with the resistor.
Oh, forgot. Measure the distance between the connecting points on the amp board, cut wires to suitable length and solder to the board.

The ways of building together a PAM-amp sre very many and the joy is to find abox or chassis that looks a bit out of

But there are many more chips with substantial output power but very efficient and very small. Below pics of boards based on TPA3310 and TDA7429. The first is said to produce 2x15W and the second 2x25W. I am also struggling with a 60W chip, the TPA3118.