Hello all, this is my first post.
I am trying to convert a 12 vdc constrant current PWM to 24 vdc. I have a 12v cooling fan on the heat sink which I put a 7812 in front of as well as the gate driver board. The negative is still common throughout the system. The fan works just fine and the gate driver seems to work ok. The problem I am having is the Mosfet is getting real hot real fast. when run in 12v system, the frequency is audiable. One the 24v system it is ear piercing and smokes the wires going to the stiffening capacitor which is 12,000 uf. The mosfet is rated for 60v, is n-channel, gate + 20v, 340A. At only 30 amps it get too hot in 25 seconds. At 12v 70 amps it barely gets warm. I don't know if the sense resistor needs to be changed to a higher value or what. I also tried to make a + - power regulator with 7812 and 7912 and had no luck. Any help would be greatly appreciated.
Thank you!
I am trying to convert a 12 vdc constrant current PWM to 24 vdc. I have a 12v cooling fan on the heat sink which I put a 7812 in front of as well as the gate driver board. The negative is still common throughout the system. The fan works just fine and the gate driver seems to work ok. The problem I am having is the Mosfet is getting real hot real fast. when run in 12v system, the frequency is audiable. One the 24v system it is ear piercing and smokes the wires going to the stiffening capacitor which is 12,000 uf. The mosfet is rated for 60v, is n-channel, gate + 20v, 340A. At only 30 amps it get too hot in 25 seconds. At 12v 70 amps it barely gets warm. I don't know if the sense resistor needs to be changed to a higher value or what. I also tried to make a + - power regulator with 7812 and 7912 and had no luck. Any help would be greatly appreciated.
Thank you!
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