I have been trying to get the following circuit to work but I keep burning out the MOSFET. I am using 2, 555 chips for frequency and Pulse width control which I am trying to use to drive the MOSFET as an on off switch. I just added the LM317 voltage regulator to keep the voltage on the gate of the MOSFET at 3 to 6 volts so I can control the amps to the electrolyzer. I am trying to get 15 to 20 amps out put. Now when I hit about 10 amps the MOSFET gate stops responding and the drain to source is full on which quickly kills the MOSFET. I had better run times before I added the LM317, about 1 minute, but still had the same problems with the MOSFET. One additional problem that I have now since adding the LM317 is the 555 that controls the pulse width is also burning out. How can such a simple circuit be so difficult. If any one knows what I am doing wrong please let me know, and thanks.
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