24. Amplifier V3

This is going to be something new, as this amplifier doesn't utilize the LM386 as an amplifier chip. Instead, it uses a Class-D amp module, which contains the chip called PAM8403. This chip (possibly with all the other Class-D chips), has an efficiency of 90%, which is a lot compared to the other amplifier types. The reason it has that efficiency is the PWM method (pulse width modulation), which means that it amplifies while switching at a higher frequency, rather than going constantly.

<Wiring>

This is a stereo amp, which it utilized 2 3.2 ohms, 20-watt speakers, on each side. This entire amplifier is powered by 2 Li-ion batteries in parallel, to increase capacity. And finally, it utilizes the 5-volt boost converter, which provides the right voltage of 5 volts, without any problems, even when the energy in the batteries is decreased.

<Full view>

It has 2 potentiometers, all for controlling the volume of the speakers, an input jack, certain switches for turning the speakers on/off, for mono, and an external connector, so you can connect more speakers! All this is crammed in the homemade wooden cube, and surprisingly, it is loud!

I would recommend the pam8403 module, for people who wanted to get started on making amplifiers!

<Typical circuit for the PAM8403>