I've been working on a full-on adjustable power supply in SPICE and thought I'd share what I have before I start building it.
Notes:
- I put R7 in to limit the inrush, I think with an NTC thermistor and an additional 2.2mF capacitor I can get better results out of the real thing. The transformer I'm using is a 115 to 24V with a listed Imax of 1.5A and 36VA power
- R6 is meant to be a potentiometer
- C5, R3, and R4 provide a delayed startup for the smoothing capacitors to charge up
Shown below is the Vin and R2 voltages, the oscillation is the current through R7. I tried to pick good models from the ltspice library to limit ideal components and out of several permutations this has given the best result!
(I'll share the full simulation when it finishes if anyone is interested)
Notes:
- I put R7 in to limit the inrush, I think with an NTC thermistor and an additional 2.2mF capacitor I can get better results out of the real thing. The transformer I'm using is a 115 to 24V with a listed Imax of 1.5A and 36VA power
- R6 is meant to be a potentiometer
- C5, R3, and R4 provide a delayed startup for the smoothing capacitors to charge up
Shown below is the Vin and R2 voltages, the oscillation is the current through R7. I tried to pick good models from the ltspice library to limit ideal components and out of several permutations this has given the best result!
(I'll share the full simulation when it finishes if anyone is interested)