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UCC28704EVM-724: About LM5023 and UCC28704EVM-724 standby power design

Part Number: UCC28704EVM-724
Other Parts Discussed in Thread: LM5023, UCC28704, UCC28700

Hello TIer,

I have project survey the LM5023 and UCC28704 and design for 40-60W(12V/5A or 5V/8A) SMPS

I saw the no load standby power(<65mW) on web side EVB information.

https://www.ti.com/lit/ug/sluubf1/sluubf1.pdf?ts=1678491284786&ref_url=https%253A%252F%252Fwww.ti.com%252Ftool%252FUCC28704EVM-724

https://www.ti.com/lit/ug/sluub81b/sluub81b.pdf?ts=1678415600005&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FUCC28740%253FkeyMatch%253DUCC28740%2526tisearch%253Dsearch-everything%2526usecase%253DGPN

So, I would like to know how to consider standby power in the design when starting to use your LM5023 and UCC28704? inductance, frequency, discharge resistor for X-CAP etc.

  • Hello,

    I have received your inquiry and will get back to you shortly.

    Regards,

  • Hello,

    When it comes to standby power you need consider all the losses in your switching power supply.

    The following link will bring you to an application note that describes how to design a flyback using the UCC28700, which uses a very similar control law to the UCC28704.   It goes through how to calculate all of the power losses in your design.  I believe you will find this useful in your design process.

    https://www.ti.com/lit/pdf/slua653

    If this resolved your issue, please check resolved at the end of this thread.

    Regards,