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UCD7138: UCD7138

Part Number: UCD7138
Other Parts Discussed in Thread: UCD3138

Hello, I am currently studying the SR behavior of PSFB.

I wonder if the PSFB converter can not use the same controller as the UCD7138.

Even though it is not an LLC converter, the PSFB has a section that conducts to the body diode during DCM operation like a flyback,

and I wonder if it is impossible to use because there is no suitable controller.

To summarize, why is the PSFB converter not having a controller to control the SR by measuring the drain-source?

  • There are two different questions that raise up:

    1) Would PSFB benefit from not letting negative current develop on SRs?

    2) Can UCD7138 work with PSFB to do this job?

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    The answer to the first question is not 100% clear to me.

    But I think that negative current on SRs can actually help PSFB to achieve ZVS at primary.

    So I am not sure if you will benefit from limiting the negative current.

    The answer to the second question is more clear.

    UCD7138 together with the DTC module inside UCD3138 are designed to work with the LLC topology.

    I am not sure if I know how to technically make it work for PSFB and specially for PCM-PSFB.

    Regards,

  • If the above addresses your question please set the status of this report to resolved.

    Regards,

  • Thanks for the answer!