[FAQ] LM5175: MosFET Margin VDS

Minki Li1

Part Number: LM5175

Can i using 40V VDS MOSFET in LM5175 when input 32V output 12V?

If no, how to calculate the safe voltage?

Thank You

0 Brigitte over 3 years ago

Hello Minki,

What is the maximum input voltage? What happens during transients?

I would recommend to at least stay 30% above the maximum input voltage including the overshoots that might happen during transients.

0 Minki Li1 over 3 years ago in reply to Brigitte

Dear Brigitte:

Input is 32V DC,and the RDSon and price of 40V and 60V MOSFET had some different....so find can it safe to use 40Vds MOSFET when 32V input

Thank You

0 Brigitte over 3 years ago in reply to Minki Li1

Hello Minki,

What is the accuracy of the 32V DC input?

I would not use 40V MOSFETs for a 32V input, but it is your decision how much margin you need in your system.

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