In a situation where an ADC is measuring an internal voltage node rather than an external input (where one has little control over input voltage), does one need to implement some over voltage protection for the ADC (clamping diodes etc.)?
In the circuit below an opamp buffers some internal signal which cannot exceed 30V, and additionally the buffers power rail limits the output to the 30V rail. Following that there is a divider which limits the maximum voltage that the ADC receives to 3V.
In this situation would it be acceptable to omit over-voltage protection for ADC, or what would be the justification for adding such protection?