I'm designing a gadget that uses an ARM uP, with 12-bit mux'd ADC and a 10-bit DAC, to essentially make a current and voltage regulated power supply. The ADC will measure voltage and current and the DAC will control a fairly soft source-follower series-pass mosfet. The customer load could be most anything.
I think it would be time-effective to simulate the control loop while the PC board is being fabbed, so we don't have to play with dynamics as much in the critical delivery path.
I can simulate it as an analog loop using LT Spice, as I'm familiar with that and could get it done quickly. It would be handy if I could also use the same model in digital mode, which would add sampling delays and maybe even quantization.
Any thoughts on how to do this?
I note here that more and more formerly-analog control loops, things like switching power supplies, motor drivers, power amps, will be going digital in the future. Some of the ARM chips are selling for under a dollar. Analog parts will, I think, increasingly be used for things like amplification, and less for computation.