USB Charger...

[IanHam]

Well I have a candy tin and wanted to put a 9v (battery) input and a 12v (car) input. And have it go out to a female USB port. I need one of these **broken link removed** So it will regulate the voltage to 5v. It is rated for 5v to 18v so I figured no problem having 2 input voltages (only going to use one at a time of course) and would have a switch so you can select 12v, 9v or off. I would like to include a on LED so I figured I would put that behind the voltage regulator. Do you think this is possible do I need any capacitors to keep the power "clean"?

Any help would be appreciated.

 

[House0Fwax]

A 9v battery won't power the 7805 for very long.
12v on the other hand is a much better idea.

As for capacitors and a LED, have a look at the following link.

https://electronics.howstuffworks.com/digital-electronics4.htm
HowStuffWorks "How Electronic Gates Work"

 

[IanHam]

I gave a few capacitors laying around a .33uf a .1uf and a 10uf what ones would you recommend or do I need to go buy some?

 

[justDIY]

wow ... I thought I'd see a lot of web based rip-offs in my day, but Ripoff-City charging $3.99 for a single voltage regulator, wtf!

here's the same part from Future (they're Canadian), $0.15:

**broken link removed**

I'd recommend you find a Cig lighter to 5v usb charger on the intertubes somewhere, and modify it to accept a 9v battery and a switch. Most of your 12v to 5v usb chargers use high efficiency switching regulators to drop the 12v down to 5v, so they operate a lot cooler. The same regulator will also accept 9v from your battery and drop it down to 5v as well.