Hi, I'm using this MOSFET.
http://www.vishay.com/docs/68998/si4174dy.pdf
My circuit is as follows:
Drain: +12V
Source: [MOSFET] -> [8 ohm resistor] -> [Ground]
Gate: +5V
My power supply is supposed to be rated to 22A, but that resistor should only be pulling 1.5A. Here is the problem, when I apply +5V to the gate of the MOSFET (I measure about 4.93V on the gate, relative to ground), the drop over the 8 ohm resistor is only 3V. If I put a 1k ohm resistor, I get the same thing. I'm not sure what's going on! Shouldn't the voltage over the resistor be nearly 12V+?
A picture of my circuit is attached.
Please advise,
Thanks,
Matt
http://www.vishay.com/docs/68998/si4174dy.pdf
My circuit is as follows:
Drain: +12V
Source: [MOSFET] -> [8 ohm resistor] -> [Ground]
Gate: +5V
My power supply is supposed to be rated to 22A, but that resistor should only be pulling 1.5A. Here is the problem, when I apply +5V to the gate of the MOSFET (I measure about 4.93V on the gate, relative to ground), the drop over the 8 ohm resistor is only 3V. If I put a 1k ohm resistor, I get the same thing. I'm not sure what's going on! Shouldn't the voltage over the resistor be nearly 12V+?
A picture of my circuit is attached.
Please advise,
Thanks,
Matt
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