So I'm trying to make a power supply using the L200 regulator. I'm using the circuit in Figure 1. Programmable Voltage Regulator with Current Limiting. I made the circuit after that design. Except that I put a potentiometer in series with R3 to make the current variable. And it does work. The problem that I'm having is this.
I want to current to go up to 2 amps. R3 in my circuit is 0.22 ohms. so 0.45/0.22 = 2.04 amps. BUT the pots I have will only go down to 0.4 ohms, I've tried like 5 of them, is this normal or do I have crappy pots? I don't know how to make the supply go up to two amps.
Is it possible to make the pot go down to maybe 0.1 ohms at least?