UCC24624: UCC24624 latch when AC input turn ON/OFF

Jack Deng

Expert 1090 points

Part Number: UCC24624
Other Parts Discussed in Thread: UCC28180,

Hi Tiers:

i used the UCC28180+L6599+UCC24624 in my 480W AC/DC project.

When the AC input turn ON/OFF(ON 1s---OFF 1s---ON 1s), i found the UCC24624 will latch the SR drives(One of the two)

The parameters of UCC24624 follow the EVM.

Do you have any good suggestions to solve this problem, thx

over 6 years ago

0 Jack Deng over 6 years ago

Expert 1090 points

update the debug status

just VG1 lock out.

1，AUX 12V to UCC24624 first, then turn on AC, the SR lock out too.

2, increase the turn ON/OFF time, if the UCC24624 VCC drops to less than 5V, the UCC24624 can work normal, if above the 5V, VG1 lock out too.

Yellow: VCC

BULE: Vg1

0 Hong Huang over 6 years ago in reply to Jack Deng

TI__Guru 73805 points

It could be caused by your layout plus MOSFET stray inductance. Can you try add or increase the resistance between VSS pin and the MOSFET source so to provide higher threshold to see if the issue can be solved. Please refer to the datasheet, 8.3.3, page 15 to page 16.

0 Hong Huang over 6 years ago in reply to Hong Huang

TI__Guru 73805 points

Per TI policy, we need to close this thread as no communication for a long time. If you still need support, please open a new thread.

0 Jack Deng over 6 years ago in reply to Hong Huang

Expert 1090 points

ok，i will pose a new E2E.

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UCC24624: UCC24624 latch when AC input turn ON/OFF