Part Number: OPA817
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Tool/software:
Hello,
I would like to ask for help regarding the usage of the PTMUXS7614DZEMR in a switchable gain op-amp circuit.
Attached is the circuit in question. For some reason, the output of the U9 op-amp oscillates at 4 MHz. I’ve tried modeling this circuit in several simulation programs (including the one TI uses), and the simulations always show correct behavior.
However, I do not have a model for the MUX switch.
Could someone please take a look at the circuit and help identify why it is behaving erratically? I can’t seem to pinpoint the issue.
The signal from U36 op-amp is very clean and stable, so the OPA817 appears to be working properly. I also have two identical channels, and both behave the same way.
The MUX appears to be working and correctly switching the resistors. In this scenario, my signal goes up to 10 MHz, which should be well within the PTMUX’s 180 MHz bandwidth.
Ok, Missed that feedback virtual offset point has tones of capacitance (I was only thinking about output capacitance ), meaning each resistor needs to have correct capacitor soldered on top