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Warrier
- 10th December 2004, 01:02
Hi all ye smart guys:

Anyone knows how to increase the resolution of the 4bit internal reference? And debounce the internal comparator?

mister_e
- 10th December 2004, 09:01
on wich device ??? Debounce internal comparator ??? why??? what type of signal do you want to measure ???

Warrier
- 10th December 2004, 13:15
Hi Steve:

On any of the following chips 10F204,12F629 or 16F628... I am trying to sample a slowly varying signal on CIN- and hold the values (36 in all per sampling cycle) in Data memory - except of course not in 10F204.

Since the dv/dt is quite small I felt I needed to "debounce" the threshold to avoid jitter at the trip point (cmcon.6 to be repeatable and stabe during read and write to data memory).
I am working with battery (Li-ion button) and am turning the vref (vrcon) and comaprator(cmcon) ON only with low PRF. So I may have settling time issues also... Sampling cycle is 1sec and PRF is nearly once / hr.

Warrier

Bruce
- 10th December 2004, 19:30
http://ww1.microchip.com/downloads/en/DeviceDoc/41215a.pdf

PICmicro Compartor Tips n Tricks. Very handy.

Warrier
- 10th December 2004, 22:05
Bruce:

Thanks for the reference..It is funny I had this pdf file for sometime now but only after you pointed out did I look at the Delta-Sigma converter example again. This is giving me ideas...... I will try the trick slowly germinating in my upper floor (it is a dull one!) and if I get it right I'll let you know.

Thanks again

Warrier