I’ve been working on a project that I need to be able to control the speed of a fan. I have a 12v fan that doesn’t have a PWM pin so it’s voltage only. I’ve hooked up a manual potentiometer and that was great but I need something controlled by the software. So I first started looking at a digital potentiometer but that looked pretty complicated. So my friend Ian pointed me to this article to control it with a transistor through PWM.
So today I tried to get that setup but was having some problems. I was able to get the voltage to go between 12v and 1v with setting the cycleduty but the fan would never respond at any voltage. I used a multimeter to test the voltages and it was showing up to 12 volts. But as soon as I hooked the fan straight up to the 12v source it worked fine.
I tried changing the frequency to different ranges but it didn’t have any affect. It seems that my PWM is functioning correctly because the voltage changes appropriately but it doesn’t run the fan.
What am i missing? Any thoughts I can try?
Btw, running a cerbuino bee with netmf 4.2.