How to build a basic power regulator circuit?

Why don't you first type this in google: "build a battery powered usb device charger" Tom

One issue with USB power is that USB devices are limited to 100mA unless they request more (in which case, they may get up to 500mA), and to 500uA when suspended (which occurs when the bus is idle for 3ms). Depending upon the device, the supply may need to be able speak USB in order to get the device to draw power. And getting something to speak USB isn't a begginer's project.

OTOH, if you just need to supply 5V, it couldn't be simpler. The circuit need be nothing more than a 3-terminal regulator, e.g. 7805.

[The 7805 needs 2V dropout, so your input would need to be at least 7V. Use a low-dropout part (e.g. LM1117) if the battery voltage is likely to dip below that.]

If either the input or output leads are long, it's worth adding a 10uF capacitor on that side of the regulator.

Most of the links on the first page refer to boost converters, which aren't suitable if the battery voltage is greater than 5V.

pretty new to electronics and I want to learn some more by

I did, and this is a great way of doing it if - you're using the same battery as in the examples sourced through google and/or you have a clue what you're doing, which I clearly do not.

Thanks for the comments everyone, I'm getting a step closer now.

It seems that the wall charger for the phone outputs at 500mA so I think a MC78M05CT is looking good unless I am mistaken. This is the most readily available for me and it puts out at the ratings I need. Thanks again for your advice.

So look at some other pages. Tom

Do you always bring so much to the table?

I suppose you just want someone to do your research for you. If you had indicated what you have done so far and where you were having trouble understanding maybe I could help. You asked to be pointed to further reading and I did that.

Tom

No you didn't, you were just being crude, and you still are. As the poster prior to you illustrated, I had stated what I was looking for, in that I did not know how to equate for the particular variable (cell) I am using. I know that I need to learn more, I therefore don't need someone like you to tell me this in mankinds most banal form.

Sorry that you were offended. I had no intentions other than to point you to some research.. Tom

You know, there's more to google than a portal into USENET.

Try the "search" side of google; search on, say, "power regulator circuit" Try it with and without quotes.

Good Luck! Rich