[volt-nuts] 3458A calibration

[Poul-Henning Kamp]

In message <7.0.1.0.1.20090810173047.01d8cd90 at tapko.de>, Predrag Dukic writes:

>How to maintain this "perfect linearity".  I read about multislope 
>ramp conversion, but that is a solution meant to shorten the

>Does anyone has some 3458a AD schematics?  Service manual can't be 
>downloaded from internet...

The ADC in the HP3458A derives its linearity from a very small handful
of components, most importantly a quite small capacitor (~120pF),
by converting the measurement of voltage to a measurement of time.

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