UCC28C45: Pulse on output with no load?

Connor Connaughton

Expert 4470 points

Part Number: UCC28C45

Hi Team,

For the UCC28C45 controller. Is it normal for the controller to pulse the output during no-load conditions?

The first image is with 20mA load, then 40 mA, and the final one that is steady 5V output is 60mA load.

Thanks!

Connor

over 2 years ago

0 Jonathan Wong over 2 years ago

TI__Expert 5870 points

Hello Connor,

This may be a problem due to the loop compensation. Other SMPS devices may also have this problem, as shown in this E2E post. Do you have a schematic available? Also, what is the input voltage?

Regards,

Jonathan Wong

+1 Connor Connaughton over 2 years ago in reply to Jonathan Wong

TI__Expert 4470 points

Hi Johnathan,

Thanks for the help here! Turns out it was a problem with the aux power. It’s hard to keep the aux voltage within the specified limits.

Thanks!

Connor

Power management

Power management forum

UCC28C45: Pulse on output with no load?