I have the following circuit to power DC motors at 5 V using a RPi 4. The MOSFET is a RFP30N06LE (https://www.sparkfun.com/datasheets/Components/General/RFP30N06LE.pdf), 1n4001 diode, 10k resistor.
When applying 3.3 V at the gate, I am seeing extremely little current flowing. I would expect 3.3 V to easily allow lots of current to flow based on:
When using a http://www.unisonic.com.tw/datasheet/30N06.pdf that has a higher Vgs(th) of 2-4 V, I see much more current flow, and the motor spins up (somewhat slowly) by itself.
I am confused as to why I am getting such little current flowing through the motor, I have to use my hand to help it start turning over. As well as why the FET with the higher threshold would allow more current to flow. I also tried with 3 units and observed the same results.