Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

  • State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 222 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

Original question:

Full-bridge topology based by UCC28251

UCC28251: Full-bridge topology based by UCC28251

Ivan Blaskovic
Prodigy 40 points
Part Number: UCC28251

Hi!

I am designing full bridge DC-DC with UCC28251. Input 220VDC, Output 24VDC/10A, fsw = 250kHz. Controller is on primary side. When input voltage is present, output goes to 24V and then controller shuts own. This process is repeating all the time. Voltage on SS pin is rising, and after is pulled down to 0. EN pin is always high. ILIM is low. HICC is low. VDD is 5V. FB/EA- and COMP are connected together and when I put probe on COMP pin, controller does not shut down and output voltage is 24V (with a lot of audible noise). When I connect some load in that condition, controller shuts down. Did you have similar problem or do you have any suggestion what is wrong?

Best regards,

Ivan