TPS54335A: Low Side FET capacitance?

Allen Wachter

Part Number: TPS54335A

My customer would like to know the drain to source capacitance of the bottom MOSFET in the TPS54335A in order to size an R-C snubber. Can you please help?

Thanks!

over 8 years ago

0 Ryan Hu (BSR-MV) over 8 years ago

TI__Expert 4035 points

Hi Allen,

below is the reply from our designer:

With the limited data I have, the parasitic capacitance for 335 LSFET is about, hope this is OK for you.

Crss(Cgd) ≈ 0.113nF;

Ciss (Cgs+Cgd) ≈ 0.126nF;

Coss (Cgd+Cds) ≈ 0.113nF, I have no data for Cds I think it should be small since we use LDMOS as the LSFET.

BRs,

Ryan

0 JohnTucker over 8 years ago in reply to Ryan Hu (BSR-MV)

TI__Guru**** 191445 points

For RC snubber design, you may consider this document as well:

5353.RC Snubber.pdf

0 Ryan Hu (BSR-MV) over 8 years ago in reply to JohnTucker

TI__Expert 4035 points

Thanks John Tucker, it's a better solution for this case.

Ryan

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TPS54335A: Low Side FET capacitance?