Hello,
I am using an MCP3204 analog to digital converter to measure the output of an OP amp. The A/D converter has a maximum input voltage of 5v, however the OP amp is powered by + and -12v. I need to ensure that the voltage into the ADC will never exceed 5 volts without changing the linearity of any voltage below that point. I think I can use two diodes for input protection: one cathode to+5V, anode to input, the other, cathode to input, anode to GND. I also have a 3.9k series resistor from opamp output and a 10uF cap, between the signal and GND.
My question is: Do these need to be 5v zeners, or can I use a 1N4148 or similar?
Any advice would be so nice!