Re :: #1 @ Nov 29, 2019

CC is not CR -- e.g. -- \( R=\frac{\Delta U}{\Delta I} \) -- so you can adjust your I by U -or- the way around -or- both (and this won't go too fast×stable unless you figure out some trans-linear Gizmo that actually defies what was just said . . .)

 

Re :: #1 @ Nov 29, 2019

CC is not CR -- e.g. -- \( R=\frac{\Delta U}{\Delta I} \) -- so you can adjust your I by U -or- the way around -or- both (and this won't go too fast×stable unless you figure out some trans-linear Gizmo that actually defies what was just said . . .)

Yes, this is a CC circuit. It’s a voltage programmable current sink. The load current is proportional to the input voltage at the non inverting op amp input - that is if the op amp and mosfet are working correctly, no wiring errors etc. The load current = V1/ R1

 

Unless there is something wrong with the op amp, there likely is a wiring error, since the op amp should not get even noticeably warm in normal operation.

other than that ↓ the opamp can warm up if it swings in between the rails due some bad biasing -- e.g. oscillates . . . yes , the 1-st post has no negative feedback against over-driven mosfet

I swapped the source and drain wires and the resistor almost blew up.