Two 1% precision resistors in a voltage divider will be sufficient for your
application. You don't want to use a "high" value because of the loading of the
877 on the divider unless you use a follower.
Rick

Lindsay Pallickal wrote:

> I am a student using a PIC 16F877 in a project and would like to read an
> analog input from an accelerometer setup that varies its output from 0-11v.
> This voltage is put out by a signal conditioner made by the manufacturer of
> the accelerometer so I have little control over it. Now I know there are
> vref pins I can use, but some analog inputs will be in the 0-5v range and
> I'd rather not lose precision on them by changing the voltage reference to
> accomodate the range of the accelerometer. How can I step down the 0-11v to
> 0-5v? Can I use two high high value resistors to divide the voltage down? I
> am considering that approach but am afraid of the effects temperature will
> have on the resistors and thus the readings, since I am told that resistors
> are prone to drift with temperature. The accelerometer will be used
> outdoors, inside a model airplane, where temperature could vary
> considerably. Also, having little background on EE, I am not sure what other
> effects might follow from using the resistors. Any thoughts or other
> approaches? I know little about EE, so bear with me if this is too basic.
> Thanks.
>
> Lindsay
>
> --

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