I'm a programmer who's been put in charge of some motor control problems and I need your help, apologies in advance for the very professional drawing.
Anyway, what i have is a PWM control board controlled by a 10K MCP-41X1 digital potentiometer with a 75 ohm wiper resistance. A mechanical 10K pot works fine (although the behavior is more on/off either/or 0 or 12V rather than continuously varying the speed, which is what I want to do) but the digital pot doesn't seem to have much effect at all -- in fact, at its lowest setting, the PWM output stays at 12V and doesn't drop at all.
Assuming that I verified that my setup was correct and that the digital pot/Arduino setup was operating properly, I would like some insight as to why the mechanical pot at least was able to turn the DMM reading down to 0V while the digital pot was not.
Any assistance in this matter is much appreciated in advance!