General Question about Circuit for a Coil


Joined Mar 2, 2015
I believe the circuit is wrong: R2 and the coil should be exchanged. As shown, the circuit regulates the voltage across the coil, not the current through it.

With the coil in M1's drain circuit and R2 connected between source and ground, the answer is yes: there definitely should be a catch diode across the coil to suppress any excessive back EMF during a sudden reduction in drive current.