Anyone heard of floating ADC inputs causing glitches in the other parts of a
chip?  16F886 device but may be similar to others?

Using the CCP1 module (compare part) to trigger a change of state of the
ccp1 output pin in an interrupt.  When the ADC is sampled the ccp1 pin will
flip high randomly at the return from interrupt.  If I have the ADC off and
the analog pins set as digital inputs - not a glitch is sight.

My analog sources that I want to sample are 47K Ohm impedance and I get
glitching in this case.  This is above the 10K recommended but there is a
0.01 uF by-pass cap on the input and this should provide the required
leakage current and current to charge up the 10 pF hold cap.  Anyway if I'm
off by a few LSBs I don't care.  The glitching is unacceptable.

It maybe that certain voltage ranges aggravate the problem.  I don't know.

Regards,

Gordon Williams

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