I am designing a small circuit where the goal is to measure the current. The CT measures the current, which passes through a shunt resistor. The ADC convert the signal so it can be further processed.
I am thinking about using jack port for the input of the CT. However, someone might think it is a power supply input and might plug in a 230 V cable.
So I want to protect my circuit against high voltage. Apparently, placing a zener diode is the simplest solution.
However it looks like my circuit is wrong. The zener diode will be connected to itself. Can someone tell me what I am doing wrong?