TIDA-01494: how to handle UCC25630-3DDBR blk pin if without PFC.

Hi, 

We used the rvcc pin for resistor divier.. 

is it fine.? if not , other power source is needed? 

Thanks,

Nick. 

Hi,

Would you confirm our schematics ( attached image) ?

I've set the 3V for divider as you see the schematics. 

Thanks

Regards,

Nick

Hi Nick,

3V would be a bit too marginal. You want to guarantee that this voltage is over 3.095V to make sure it can work across all production lots:

So change R58 to 110k would make this work.

I hope this answers your question.

Hi,

We will try that.. 

Thanks

Regards,

Nick. 

Hi,

We produced the custom board(10EA). but some boards(5EA) are not working.

I've changed the resistor. but They are not working. 

I think there are some other conditions for booting.. 

let us know the conditions for booting.. 

Thanks

Regards,

Nick. 

Hi,

I've changed the SR Chip UCC24612-2DBVT to a new chip. it's working.. maybe it's dead for some reason.

I don't understand. 

Thanks anyway.. 

Nick. 

Hi Nick,

Glad you got it working. I was going to ask you to measure the voltages at VCC, RVCC, and BLK. Do you have any idea how the SR got damaged?

Hi, 

I don't know that exactly. but I think the LLC works abnormally and it affects the SR Chip.

or there are probably some soldering problems.

If we find the exact reason, let you know that.

I think 

The important thing is that BLK is set to 3.2~3.3V for the margin (110k resistor) like your advice.

Thanks,

Nick.