Having an iPod is great fun. However, the battery must be recharged regularly. It can be very annoying then having to start up your PC, only to charge the iPod. Also, when you are on holiday, you don't always have a laptop with you. So how do you charge the iPod then? Here you have the solution: an iPod-charger that you can plug into your wall socket. And it's much cheaper than the ones Apple offers. So why not try and build your own one?

Schematic of iPod nano charger (15.9kB PDF-file)

The schematic is actually very simple. It contains a connector where you can connect a standard 9V adapter. A diode protects against reverse voltage connection. Then there is a 7805 regulator that converts the 9V of the adapter to 5V needed by the iPod. The two capacitors are added for stability. If you want to make it really cheap, you can leave out the 4.7µF capacitor. On the other hand, if you want to make it safer, you can add a fuse of 625mA between pin 3 of the 7805 and pin 1 of the USB-connector. This will protect your iPod from overcurrents. That's all there is to it.

When you try to make the circuit yourself: first measure the voltage on the USB-connector of your charger. It pin1 must be 5V more positive than pin4! If this is not the case, you made a mistake somewhere.

Cadsoft Eagle project of iPod nano charger (46.4kB ZIP-file)

Eagle project containing the schematic and a board layout of this small project.

Here you can see a prototype of the charger, soldered on a piece of breadboard. Up to now I didn't find the courage to make the PCB and put it in a fancy little box. I'm happy with what I have here. In fact the only reason why I put the picture here is to "prove" that the charger really works.

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