UCC27211A: UCC27211A

Loc Ngo

Part Number: UCC27211A

Tool/software:

Hi,

I am currently used UCC2721A gate driver for my half bridge LLC with input of 48V, seeing a high glitch of the top and bottom Fets at the same time during Fet turn on and caused a shoot through. Do you have a technical explanation that can cause this issue? Would you please share the Simplis model of half bridge circuit using this driver?

Thanks

over 1 year ago

0 William Moore over 1 year ago

TI__Genius 14145 points

Hey Loc,

Thank you for reaching out to TI with your questions regarding the UCC27211A.

Looking at your schematic, the bootstrap capacitor C2 is not as large as expected and will not be able to store enough energy to source current for the high side. Also the bypass capacitor C1 should be placed close to the gate driver and after the R7 resistor. Take a look at this application note discussing selection of these components.

Bootstrap Circuitry Selection for Half-Bridge Configurations

Can you share the waveforms of HO and LO and confirm the deadtime between them?

Thank you,

William Moore

0 William Moore over 1 year ago in reply to William Moore

TI__Genius 14145 points

Hey Loc,

Have you been able to resolve this issue? If so, can you please explain what you found? Or, can you provide updates to the above questions and the status of the issue?

Thank you,

William Moore

0 William Moore over 1 year ago in reply to William Moore

TI__Genius 14145 points

Hey Loc,

I am closing this thread at this time under the assumption that this has been solved on your side. If there is further help needed, please reply and reopen the thread.

Thank you,

William Moore

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UCC27211A: UCC27211A