I am trying to build a simple totem pole driver using transistors. I HAVE had it working using a single transistor to fully saturate the mosfet. It's an IRF510 mosfet.
I am using the circuit show in the first post here: http://forum.allaboutcircuits.com/showthread.php?p=177826
Right now I am just using 5v all around since i'm testing with an led, and the problem is that when I send 5v to the enable line, my led lights up nice and bright, but when I remove power from the enable line, instead of the led turning off, it just dims to about half brightness. Grounding the enable line makes no difference.
If I replace the mosfet with an led, the led turns fully off and on as expected, which leads me to believe the problem is with my mosfet.
Using a single transistor I had the mosfet sending 12v to a motor and I noticed no change in temperature of the mosfet. Did I somehow burn it up between single transistor and totem pole driver circuit? I was always very careful to make sure that all the pins where stuck in antistatic foam or all connected to ground until I plugged it right into my circuit.
I will try the single transistor setup again and see if it appears to still work.
I am using the circuit show in the first post here: http://forum.allaboutcircuits.com/showthread.php?p=177826
Right now I am just using 5v all around since i'm testing with an led, and the problem is that when I send 5v to the enable line, my led lights up nice and bright, but when I remove power from the enable line, instead of the led turning off, it just dims to about half brightness. Grounding the enable line makes no difference.
If I replace the mosfet with an led, the led turns fully off and on as expected, which leads me to believe the problem is with my mosfet.
Using a single transistor I had the mosfet sending 12v to a motor and I noticed no change in temperature of the mosfet. Did I somehow burn it up between single transistor and totem pole driver circuit? I was always very careful to make sure that all the pins where stuck in antistatic foam or all connected to ground until I plugged it right into my circuit.
I will try the single transistor setup again and see if it appears to still work.