At 09:17 AM 3/7/97 -0700, you wrote:
>OK, I'm really intrigued but I admit to not understanding this.  I am
>currently in a prototype stage using a PIC17C42 and an external ADC.  I
>would really like to get more resolution.  Is there any chance of a more
>detailed explanation?  What I don't understand is how the square wave
>increases the resolution when the ADC (an 8-bit for example) can only
>report 256 decision levels.  Thanks!

Oh, yeah, sorry.

Take the sum of the samples.  For example, 16 samples will give you 4 extra
bits, 32 samples 5 bits, etc.

I usually have to throw away 2-3 bits, resulting in 4-8 times the number of
samples, but that's with a cheapo 8-bit A/D in these chips, with little if
any filtering of the analog line.  If you're using a better A/D and/or an
analog filter, you might to better.

Sorry for only giving you the hardware side.

Andy

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Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
          Hardware & Software for Industry & R/C Hobbies
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