I have alot of projects that have most of the design work finished, but need finishing touches and the all important first build. These projects use the venerable ATmega168.

A balanced, bridged two channel amplifier. Idea came from DIYaudio. Actually this still has a fair bit of work left to do.

A super gnarly DAC + headphone amplifier. Has balanced outputs so it can be connected to the amp above. My attempt at “hi-fi.” I got a lot of inspiration and some schematic symbols from a project on DIYaudio.

A tiny robot/experiment board that has USB, 2.4Ghz wireless, dual H-bridges, and most pins brought out to headers. This is going to have to be manufactured at a pretty good board house because of the tight spacings on the CC2500 radio.

An LTC3401 boost converter.

An LTC1871 boost converter.

A “soft start” … this basically switches a power resistor in line with the primary of a transformer for a few milliseconds to limit in-rush current. The whole idea is that this circuit will let you pick a fuse that is appropriately sized for a large transformer since you won’t be having huge transients when the transformer is first plugged in. It’s a dangerous circuit because it works with live mains voltage, so I am kinda nervous about building it. Circuit came from DIYaudio, the layout is the only work I did.

RGB LED controller… after seeing Sylvain Bissonnette’s RGB LED controller, I just had to make my own. My version uses one LM3404 per color and has USB and IR interfaces.

In case you can’t tell, I like to layout PCBs. Keep checking back as I plan to complete these designs and publish ALL of the files.