Considering a OpAmp in inverting configuration with a gain <1 what maximum input rating do I need to respect?
- single 3.3V supply, rail-to-rail OpAmp
- gain of 0.66 via negative feedback resistor ratio of 330k/500k Ohms
- bias voltage on non-inverting input of approx 1.9V via resistor divider
- input signal swing of GND to 5V
The OpAmp is rated for 0.3V above/below rails which should be fine when I can assume that the device will keep the inverting input equal to the bias voltage of 1.9V when in operation. Is this reasoning correct, or does the 5V input violate the maximum rating.
I am designing a anti-aliasing filter with cut-off around 150Hz. I am not currently referring to a specific device but think that the MCP6001/2/4 could be suitable.