Low current cut-off circuit
Here's my query:
I'm trying to design a simple circuit that cuts-off when the current through a time-varying load falls below a threshold value.
Basically, I am electrochemically etching a piece of wire, which initially has a resistance of ~1k Ohms. When the etching is complete the resistance rapidly (few 100ms) increases to essentially an open circuit, at which point I want to automatically break the circuit. The etching requires a constant voltage of ~3V dc.
I think I can use some sort of comparator circuit, but I'm not sure how best to implement this - any assistance would be appreciated!
Cheers.