bcjames wrote in message . ..
I want to build a 5 Volt power suppply to run my PDA in my
glider from the 12 volt battery. Sometimes I use a 14 volt
battery too, so it needs some input voltage range. I'm
looking for suggestions and a DigiKey part number for a
suitable 1 amp DC/DC integrated power supply chip.

I'd like:
at least 80% efficient
no radio noise
Vin of 10.5 to 16.5 volts
Vout 5 volts
1 amp
low cost

I've looked at the LM2825 and the LTC1174-5, but I'd like to
hear from anyone who's done this.

Thanks

Hi;

Have a look at the TI integrated switching regulators. This part and
a couple of capacitors will be all you need.

http://dkc3.digikey.com/PDF/T043/1317.pdf

Here is an app note for use in a car:

http://focus.ti.com/lit/an/slta010a/slta010a.pdf

These are nice overload protected parts and will get you going pretty
quickly.

Scott