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Take a potentiometer as a voltage divider?


New member
Good day, all

I have a small fan setup and I wanted to add a potentiometer to use as a variable resistor. I checked some steps of how to wire a potentiometer. I've come up with this design which uses a logarithmic potentiometer in place of a series resistor.
Initially, the red line did not exist, I was only going to use one terminal and the wiper, but while trying to come up with an appropriate resistance size I could only find information about a voltage divider.


(I'm sorry, there is a typo on the diode label)
I was wondering if this is correct,it doesn't look right to me, but I'm relying on my terrible electronics knowledge from elementary school, which is known to be less than optimal at times.

Anyone have ideas of it? Many thanks.


New member
I agree with dl324. Remove the potentiometer, connect the lower end of the fan motor to the transistor collector, and use PWM mode on GPIO18 to control fan speed.
Also, you need to see how much current the fan needs, and whether a 2N2222 transistor can handle it.