I'm working on a data acquisition system that's selecting among 30 inputs (0 to 30V range) via muxes and digitizing them to an accuracy of about 100 uV. Each input has an RC filter (10k / 0.1uF) before the mux, and then an op-amp buffer follows the mux.
The settling time between samples is adversely impacted by the comparatively fast slew rate of the output of the mux versus the slew rate of a 30V rated precision op amp - most op amps have input protection diodes that activate in this scenario, which drains the filter capacitor a bit during slewing requiring a long settling period to recover.
The new OPA192 is ideal for this application, but is brand new and has not yet been released in any of the smaller packages or as a dual/quad. Are there other TI parts with similar capabilities? Many datasheets do not mention maximum differential input voltages, or whether back to back protection diodes exist on the inputs, so finding other useful parts is difficult.
Thanks,
-Greg