TI Team,
We are using the UCC256404 in a design and have some questions- two of which are below:
- Is there a way to correlate the BMTH threshold setting to output power/current/voltage or similar? Because it is for an audio product, our design runs at very low power most of the time (<30W) but the SMPS has the capacity to run continuously at 145W as required for maximum continuous volume. A BMTH threshold of "0.6" as shown in the data sheet example doesn't offer any way to correlate at what condition on the secondary side we will enter into boost mode.
- Any thoughts on how to extend the soft start period to several hundred milliseconds? We have a significant amount of bulk capacitance on the output rail to help with transients. Currently, the LLC hits the OCthreshold and sort of "hiccups" until it gets that capacitance charged. I would like to extend the softstart time (we can handle the delayed start without issue) to a longer period of time- but it seems maybe that the highest value capacitance we can use for the soft-start capacitor is 470nF. We can adjust the RLL upper and lower, but to get the sort of time frames we're after, we end up with several mega-ohm resistors.
Thanks in advance,
Cody
