AC Charger for USB Powered Devices

The project demonstrates how an old AC wall wart was used to create a homemade USB charger for handheld electronics such as Personal Game machine, Digital Camera, or MP3 Player.

Portable ECG Unit Powered by Solar Energy

Illustrated in this project is a solar-powered portable electrocardiogram (ECG) unit that is built by a student from the Swiss Federal Institute of Technology.

Lab Power Supply with 250W Output

The project shows how a power supply from an old PC can be converted to deliver high currents in order to power electronics projects.

DC Power Supply in Programmable and Digital Form

The objective of the project is to design a DC power supply based on a microcontroller making it cheaper but with a lot more features.

Simple Adjustable DC Power Supply

This project is a variation on those using linear voltage regulator chips to power low-voltage experiments wherein it uses a low dropout regulator to allow lower input voltages and a fine adjustment system.

High Voltage Switch Mode Power Supply for Nixie Tubes

The small-circuit project illustrates a switch mode power supply (SMPS) that boosts low voltage to the high voltage require to drive nixie tubes while being operated on batteries or low voltage wall-warts.