14. Off Isolation vs. Frequency of your datasheet)?
I am going to use the ADG734 in an audio application, where a very good off
isolation is required in the audio frequencies, hence my question.
If I zoom on the TPC 14. figure, I seem to see that the curve starts to rise at
frequencies lower than 30kHz and that's obviously of a concern.
The isolation curve should not be rising. I think that is an artefact of the
data sheet creation process.
The isolation will be at least as good as it is at 30kHz. The reason we don't
show lower values is that the information is collected using a spectrum
analyzer and at lower frequencies, the measurements run into the noise floor of
the analyzer itself.
There is no physical process that would cause the device to have less isolation
at lower frequencies, which is why it is only shown for the regions of