UCC28740: Cannot Startup VDD UVLO

Nhat Dao Quoc

Prodigy 60 points

Part Number: UCC28740

Hello,

I am making a new iteration of a power supply with an UCC28740

Turns: PRI = 100, SEC = 10, AUX= 10

Chanel yellow : VDD
Chanel pink: VGS mosfet
Please help me with this Troubleshooting.

over 3 years ago

0 Mike O' over 3 years ago

TI__Guru 69105 points

Hello,

If VDD is cycling most likely the device is entering a fault. I have attached and application note that discusses PSR fault sensing most common issues and how to resolve. It also explains how PSR sensing works. This information should help you trouble shoot your issues.

Regards,

2804.Clean PSR Sensing App Note 10 5 20B.pdf

0 Nhat Dao Quoc over 3 years ago in reply to Mike O'

Prodigy 60 points

Hi Mike O'
I really appreciate everything you’ve done. Thanks
Regards

Power management

Power management forum

UCC28740: Cannot Startup VDD UVLO