Gamry Instruments PCI4/300 Potentiostat/Galvanostat/ZRA, Руководство оператора

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Appendix E – Auxiliary A/D Input Characteristics -- Filter Selection
6-16
Filter Selection
J602 controls filtering of the Aux A/D input. With J602 removed, there is no filtering on this input. With J602
in place (the default setting), a single pole RC filter is used to limit noise into the A/D. The nominal cutoff
frequency of this filter is 20 Hz.
Note that source impedances greater than 1 k
Ω
will appreciably lower this cutoff frequency. When the Aux
A/D input is driven by a source with an output impedance of 1 M
Ω
, the frequency cutoff will be less than 0.25
Hz.
Aux A/D Specifications
These specifications apply to all PCI4 boards:
Range
±
3.276 volts
Input Impedance
100 k
Ω
(approx) J603 & J604 installed
or
10 G
Ω
(typical) J603 & J604 removed
Input Bias Current < 10 nA J603 & J604 removed
Filter Cutoff 20 Hz
±
20% J602 in place with
Zsource < 1 k Ω