So, I’m tinkering with the ATtiny 3224 and its PWM capabilities. I can get 256 bits of resolution per cycle at 78.125kHz.
If I drop to 32 bits, that gets me to 625kHz, as shown in the screenshot.
I’ve done some searching but I may not know the right term and I’m probably looking for a rule of thumb.
What sort of resolution do you need to regulate a DC/DC switch mode? (in this case a pure resistive load that doesn’t change)
I think it might be something like a factor for required percentage of change of switch ON time. Such as, you should generally be able to modify your duty cycle by increments of 5% or 0.5% or whatever for proper regulation.
Does this factor have a name?
I hope you mean 256/32 increments and not actual bits? I haven’t heard of a microcontroller with a pwm resolution above 16 bits
Think it depends a lot, higher frequencies means smoother current flow, higher resolution means less fluctuations, but if you have enough output filtering you can get away with pretty much anything i think
The period is divided up into 32 pieces, instead of a 256 bit width, if that makes sense. So, the frequency is 20mHz/32 = 625kHz. 0b100000 / 0x20.
Yeah, and with the load I’ll run, it’s not real critical. I just figure there has to be a name for this sort of tuning. If I know what it’s called, I can read up on it.