I'm currently building a LPF using a differential op-amp configuration and a multiple feedback topology. The opamp I'm using is the THS4131. I supply the opamp with a +/-12V power supply. My question is what capacitor voltage rating should I use? I know for a decoupling capacitor where there is a ground, that anything above 12V + some fudge factor should be enough. However, I'm using differential mode so there's a common mode ground which I'm not too sure about. Furthermore, the capacitor is used for the topology and not for decoupling.

I've tried using a 16V rating cap and I'm unsure whether this is too low. I've already built the circuit and the opamp is heating up when powered. I'm checked the traces and wiring so it seems fine so I'm thinking it's due to this voltage rating.

So my question is what voltage rating should I be using?

edit: Schematic added


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    \$\begingroup\$ Post a circuit. \$\endgroup\$ – Matt Young May 16 at 0:56
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    \$\begingroup\$ The THS4131 is a 150-MHz amplifier. Caps rating are important, but the IC is heating up likely because your feedback network has parasitic capacitances that you forgot to account for, and the circuit is likely ringing as hell at a frequency you can't see. Post your schematics and PCB layout if you want a better analysis. \$\endgroup\$ – Ale..chenski May 16 at 2:55
  • \$\begingroup\$ I've added the schematic. I've also attempted it on the breadboard and have the same results (not working). \$\endgroup\$ – kurcio May 16 at 4:16
  • \$\begingroup\$ I've also just tried to do a single ended inverting opamp to see if the IC is still working and my output has a much larger frequency than the input. Not sure it has broken (same thing happen when I tried with a fresh IC). \$\endgroup\$ – kurcio May 16 at 4:25

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