I received an application ideas book called "Dream Machine Reference
Book" from Phillips.  In it they talk about a method of using
dithering to effectively get 12bit resolution out of an 8bit A/D. It
consist of using PWM configured as a DAC to feed a triangular 100mV
waveformthat is AC coupled,  back to the original input.  The input is then
oversampled and by averaging the number of readings and the combined
dither/input voltage, the technique achieves an  effective 12-bit
resolution.   Don't ask me how it works, I just wrote down what I
read in the description.

It sounds like something which could be very usefull when using devices
like the PIC16C74.   However, I can not quite understand how the
teqhnique actually works.  Does it make any more sense to anyone else
out there?

Regards
--
Werner Terreblanche
wterreb@plessey.co.za (work)  OR  werner@aztec.co.za  (home)
Plessey SA, PO Box 30451, Tokai 7966, Cape Town, South Africa

Check out my Variometer Kit on:
  http://www.aztec.co.za/users/werner/variokit.htm
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