>What resolution do you need?  For example, if 8 bits is enough you can use
>1/4 range of a 10 bit A/D, which only requires 0 to 1.25 volts.  Even less
>if you only need 6 bits, for example.

8 bits is going to be fine.

>What is the maximum current or power rating of the sensors?

Thats one thing I was unable to detiremine, so I'm going to have to make
some guesses and play it safe. I think a range of 20-30 mA shouldn't be a
problem.

>For example, if
>you wanted the 187 ohms to result in 5V, it would require 28mA and would
>dump 134mW into the sensor.  If this is acceptable, you could run a fixed
>current thru the sensors and get the desired 0-5 volts out directly.

I like the idea of a fixed current source through the sensor, I'll have to
look more into this. One of the original problems I had was keep the current
through the sensor low enough.

>Since
>you have software that can apply corrections, this could be as simple as a
>200 ohm resistor to are regulated 10V supply, for example.

This will be an automotive project, so I'd like to just use my existing +5v
power supply, and not have to add another.

>If you use the
>output of the sensor directly, then be sure to put a 10K ohm resistor
>between the sensor and the PIC pin.  Otherwise an open sensor will blow up
>the PIC.

Thanks for your help!

Aaron

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