GBAmp2

Class-DOpen Source HWGBCDMGPCB

What is it?

This is a "Hi-Fi" Class D amplifier for Gameboy Color internal speaker.

How it started

I've got a GBC and found a rusted speaker with crackling noisy sound and it was barely hearable. Headphones is not the way out.

So I searched my parts bin for some tiny amp ic and found TI's Class D mono amp. Exactly what I need. I quickly designed and made a small pcb to test it out with some random phone loud speaker. Sound was great and loud.

New in version 2

For the next version I selected another Class D amp from Analog Devices, it's even smaller. I picked the smaller one so I can make a pcb which fits in the speaker cutout in GBC, just on top of the speaker.

New in version 2s

In this one I used TI Class D amplifier ic again. Also mixing stereo signal to the speaker.

Benefits by using it

Main benefit is the sound volume, it's much louder than the integrated amp, and takes no space inside.

Class D amp is very power efficient, this means longer battery life, significantly longer.

If you add an additional capacitor on the power line you can get cleaner sound than stock (using line out connection). But with GBAmp2s version you probably don't need an additional capacitor, there are plenty fit on the pcb.

Open Source Hardware

GBAmp2s pcb is an Open Source Hardware, licensed CC-BY-NC-SA. To get the source files, write me a message via Contacts.

Buy

Order Now at Tindie. Also available at kitsch-bent.

Troubleshooting

If you have a little distorted but loud sound on not max volume settings then swap speaker wires.

If you have the same after swapping, then probably volume control is rusty.

If you do not have sound check all connections and wires.

If you have very low volume and heavy distorted sound then amp is probably dead. Or speaker is dead, check with another speaker.