I have an existing device with low-noise differential amplifier at the front end. It uses two LT6200 op-amps in inverting configuration and has a gain of ten.
Occasionally, that's too much gain, and an attenuator is pugged in in front of the amplifier.
I want to make the gain electronically switchable without hurting the noise performance, so I want to avoid analog switches.
These op-amps have a disable pin. It seems that if I disable the op-amp then the signal goes straight through the input and feedback resistors and on to the next stage without gain. That's handy as I can control the disable pins with a spare uC output.
As long as the signal doesn't exceed the supply at the op-amp pins, that should work fine. Shouldn't it?
Cheers