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Problem with overheating of switching MOSFETS

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clairvoyant13

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I drive 2 MOSFETS from one opamp (358).
But, MOSFETS become warm very soon.
Is it switching time problem or what? and how to improve this situation?
Bye!!!
 

Re: Switching MOSFETS

calculate the switiching frequemcy and duty ratio.

then calculate the losses ( power dissipation ) and check whether it is more than max power dissipation. IF that is the case, put some heat sink if it solves the problem.
 
Re: Switching MOSFETS

For me it look like switching time (rising and falling) problem and driving two MOSFETS of one general purpose opamp is rather NOT good engineering achievment ..

One option to slove this problem is to put drivers between opamp's output and MOSFETs' gates - separate for each MOSFET ..
BTW: Do you need this opamp at all???

You can consider CD4050 with 6 non-inverting gates, which can be connected in batches of two or three in parallel - as shown in the attached example (they use CD4049 and invert the control signal twice; you can do the same, or just use non-inverting gates like CD4050) ..

Regards,
IanP
 
Re: Switching MOSFETS

Thanks guys.
I drive mosfets of paralleled gates and now they can work for hours being hardly warm.
Thanks again.
Bye!!!
 

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