AD2 Impedance Analyzer Reference Resistor Selection

[Systems_Engineer]

For the Analog Discovery 2, in Section 2 of the "Using the Impedance Analyzer" documentation, a table is provided to identify proper selection of a reference resistor versus a capacitance or inductance being analyzed.  ( Table image attached ).

The "Ref Resistor" and "Inductance" columns of the table list values in successive powers of 10.  However, the "Capacitance" column in the table does not provide an entry for 100 nF ( i.e. 10 times 10 nF or 1 uF divided by 10 ).

If the Table is incorrect, please provide a corrected version of it.

If the Table is correct, please explain the reason for the apparent inconsistency.

[JColvin]

Hi @Systems_Engineer,

I'm surprised to say I've never noticed this before; the engineer most familiar with the Impedance Analyzer specifications who routinely checks this section of the Forum should be able to provide some more insight on this (though there likely won't be a response until tomorrow as they are in European timezone).

Thanks,
JColvin

[attila]

Hi @Systems_Engineer

As stated above the table, these are the "approximate" resistor values. The reactance depends on the frequency but lower capacitances are usually operated at higher frequencies and higher caps at lower frequency. This is why the table values are not proportional.