Matt Rhys-Roberts wrote:
>> Apply the same voltage to all during production test and store
>> calibration values in EEPROM.
>
> a) ADC and its attenuator (say 1% tol.) are calibrated once against a
> precision external source

This can be just as easily applied to multiple attenuators.

> b) Multi HV unit can then self-calibrate each channel, as the
> attenuator is switched between HV outputs.

How is that self calibrating?  You can't calibrate the system with a signal
you are trying to measure.  You need a reference somehow.  If you're worrie=
d
about drift after initial calibration, then you have to occasionally switch
in a calibrated input.  However, I wouldn't call that "self calibrating".


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