Buck regulator MOSFETs heating

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kotnikyeah
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First question asked Welcome!
Hello everyone, I use 4 parallel IAUC70N08S5N074 mosfets as a top mosfets, and 4 parallel mosfets too, as a bottom mosfets, in my sync buck topology. I wonder if they will get hot, how can I calculate and aproximate how hot they will get, so I place more in parallel to devide power between them. Some article should help, or just the experience in general. Thanks Buck specs: Vin= 48V, Vout= 18-26V, Ioutmax=40A Thanks guys !
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Abhilash_P
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50 likes received 500 replies posted 250 solutions authored

Adding to my previous response, 

The SOA graph from the MOSFET datasheet has to be verified if the MOSFET is working within its rated specs. 

The top side switch conducts for DT time and the bottom switch conducts for (1-D)T time. The switching frequency and the Vds from the spec should be within the MOSFET ratings obtained from the SOA graph. 

For more details please refer the link that I have shared in my previous response. 

 

Regards,
Abhilash P

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Abhilash_P
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50 likes received 500 replies posted 250 solutions authored

Hi

   

Thank you for posting on the Infineon community. 

Please go through the following link to know more about MOSFET paralleling.

MOSFET paralleling. 

This page has all the necessary explanations related to MOSFET paralleling. ( documents, video lectures and trainings). 

 

Regards,
Abhilash P

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Abhilash_P
Moderator
Moderator
Moderator
50 likes received 500 replies posted 250 solutions authored

Adding to my previous response, 

The SOA graph from the MOSFET datasheet has to be verified if the MOSFET is working within its rated specs. 

The top side switch conducts for DT time and the bottom switch conducts for (1-D)T time. The switching frequency and the Vds from the spec should be within the MOSFET ratings obtained from the SOA graph. 

For more details please refer the link that I have shared in my previous response. 

 

Regards,
Abhilash P

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