• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 62 subscribers
  • Views 301 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Current Synthesis in UCC28070

David Woo
Prodigy 530 points
Other Parts Discussed in Thread: UCC28070

In our UCC28070 data sheet, we only have small description on the current synthesis. It is not easy to under what is the action or theory inside the chip.

Can you tell me what is doing inside the chip? How can it generate the current? Does it have any side effect on the power factor when operating at light load, high line Vin?

Please help!

  • 0
    TI__Guru* 86266 points

    Hello David,

    The Rsyn resistor programs a discharge current for a 1nF internal capacitor.  When the gate drive turns off the current in this capacitor is disharged and the volatge across this capacitor synthaysis the boost diode current.

    Regards,

    Mike

  • 0 in reply to Mike O'
    TI__Prodigy 530 points

    Mike,

    Thanks for your support. Do you have any block disgram or circuit show this synthesis? Do you have any calculation formula on this? Our customer wants to know more details on this design. They worry about this and have no confident to use this if they don't know the details. Thks.

    Rgds,

    David

  • 0 in reply to David Woo
    TI__Guru* 86266 points

    Hello David,

    This circuitry is proprietary and we cannot give out the exact circuitry so competitors will not copy it.  There are equations for setting up this pin in the data sheet and application note.

    Regards,

    Mike