Alex over at InsideGadgets has written an article detailing the build of his programmable power supply: A small programmable power supply with 4 digit segment display using an ATtiny84 to allow 3 programmable voltages and ability to adjust the voltage higher or lower. Output range is 0.3V to 12.5V.
We’ve been working on a new power supply in the forum, so this programmable power supply project was an interesting read. The PIC adjusts the output voltage using input from a keypad. Via Hack a Day.