Re: HCT4051 leakage

consider the capacitance at the input of the A/D.

when the mux changes channels, it has to charge/discharge to the new
value through the series resistance

it might take a long time for the cap to reach final value accurate to
24 bits.

this leads to what appears to be crosstalk between the channels

you can improve the situation by setting the mux to channel with the
fixed ref voltage in bettween reading active channels

it seems hard to belive a small c could do this but if you are going
for 24 bits, it may be part of the problem

Mark

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