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UCC256403: How the latch of TIDA-010081 reference design work ?

Part Number: UCC256403
Other Parts Discussed in Thread: TIDA-010081,

Hi team,

thanks for your support always. I have a question about latch of TIDA-010081 reference design. 

TIDA-010081 reference design |

As I know that when latch be happened(OV or OC or other protect function), the system will be BLK then if you want to return to normal work will need to restart it.

However, My customer notice that At Optional OVP & OCP latch. when OV or OC are triggered then LATCH will from high to low.   

the U11 will be turn on. base of U11 turn on Pri_15V will supply voltage tuning 2N7002 on and pull BLK to low.

When the BLK to low. UCC25630-3DDBR(UCC256403) will BLKStop. at this time, system shunt down then Vo=0V & Io=0A it mean OV & OC wouldn't be triggered that LATCH return to high. U11 turn off then BLK won't be pulled low but return to high.

the system will get into the cycle: OVP be triggered -> BLK to low ->Vout shunt down -> OVP not be triggered -> BLK to high ->Vout recover then OVP again(?) 

Finally, I'm confused that why system will not into latch to wait to be reset. but enter to the cycle I analyze.

I must have misunderstood at some part. Would you please explain it?