UCC256404: Power management forum

Rahamadullah A

Part Number: UCC256404

Hi TI team,

I have a query on LLC controller UCC256404 .When burst mode is disabled, FBreplica needs to be higher than BMTL at steady state. Otherwise, LLC output voltage will lose regulation as it continues deliver more energy than what it is demanded from the feedback.

How can i ensure in the design that i always maintain FBreplica higher than BMTL at steady state or which parameter has to be altered outside the IC to maintain this condition? Please advice.

2 months ago

0 Mike O' 2 months ago

TI__Guru 69905 points

Hello,

Your inquiry has been received and is under review.

Regards,

0 Mike O' 2 months ago in reply to Mike O'

TI__Guru 69905 points

Hello,

If you disable burst mode you might want to add a pre-load to keep the output in regulation if needed. Sometimes the opto loading is enough.

You also may want to study this to see if a pre-load is required. I would leave a place for a pre-load resistor and see if it is needed before you add it. It you do need one I would put a potentiometer on the output first and dial it to exactly the impedance you need to keep the output in regulation.

Regards,