Hello,
I have a simple n-channel MOSFET circuit to statically switch on or off a 36Vdc supply to a 30 Ohm resistive load. The MOSFET's drain is connected to the +36Vdc supply, the source is connected load resistor, the other end of the resistor to GND. When Vgs is around zero, the switch is "off" and zero voltage supply to the resistor, as it should be. However, with a Vgs of 9.5V, the MOSFET doesn't seem to be fully on and overheats quickly. I'm getting just 6V on the resistive load, so a Vds of 30V instead of virtually 0V. The MOSFET is an IRFZ44N : VDS up to 80V, RdsON = 13milliOhm at Vgs=10V&10A, IdMax=10A, Gate threshold = 4.9V max (typ. 3V).
Am I missing something obvious here? It's such a simple circuit.
Thanks for any help.