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Mosfet Gate ringing and overheat

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Thamilarasan

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I have designed a push pull inverter. Driving 48V dc to Ac. I have used the push pull configuration. When the MOSFETs are switching alternatively the mosfet getting heated.

Then i noticed that the gate is ringing. How can i solve this? Why my mosfet it being heated?
 

It is heated becasue it dissipates power, I guess the drain current multiplied with the drain-source voltage is not zero for a transition period.
Ringing can cause by inductance at the gate or driver circuit can produce it. Share your circuit's schematic at least.
 

Here , my schematic
 

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Here, my waveforms
 

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you need to heatsink the mosfets - and put snubbers across the D-S on each for the ringing at light loads ...

- - - Updated - - -

add 10uF to pin 8 of the gate drive chip
 

How to calculate the snubber circuit values? Can you please provide me the schematic?
 

It depends on the total power of the inverter and the leakage inductance of the transformer ...
 

Hi,

From the waveforms I assume there is no true GND plane of your PCB layout.

The missing capacitors have already been mentioned.

Please read through the forum, there are many threads discussing all the same problems ... including snubber values.

Klaus
 

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