My scenario involves a pre-amped circuit (3rd party) connected to my custom PIC project board via a 13-pin cable/connector. A number of analog signals will be coming into my board, and power will be sent across to the pre-amp.

Here's the challenge...

My PIC circuit is obviously powered at 5v. The pre-amp circuit requires 7v power to be delivered. I'm trying to determine if I need to add a 7v voltage regulator on my circuit board in order to send the appropriate voltage, or if I can somehow use the 5v power that's already on the board (for the MCU). I guess I can always have 2 voltage regulators (5v and 7v) connected to the main power source, but would rather not.

Also, the analog signals coming back across the 13-pin cable (into my board) are 7v - so should I assume that I need to "step down" to 5v before connecting them to the analog inputs on my PIC?

Is there an easier way to do this? Can I just use a single 7v voltage regulator and run my 18F452 (or any other PIC) at 7v to make things easier? Bad idea, huh?

Or should I try sending 5v power to the pre-amp? No harm, sending less power than required, correct?

I'm pretty much a newbie, so appreciate any help. Thanks!!

- Mark O