UCC24612: Back powering LLC output with Synchronous Rectifier (Follow-Up)

Hey Ben!

We are revisiting this subject and had some follow-up questions.

This supply is applied during part of the manufacturing process, to allow an audio sub-assembly to be tested without the need for an external supply. So, removal and reinstallation of a soldered component doesn't work within the production flow. We had a workaround in place that isolated the net for this test, but due to a key component going EOL, that is no longer an option. (We also received feedback that this method was clunky and difficult to complete.)

So, we're back to needing to power the load connected to the LLC/SR output with an external supply. I'd like to avoid the losses that would come with a series connected diode or PFET. I assume that your concern is related to ringing related to abrupt application and removal of the external supply- is that correct? If so, I think we can control this by slowly ramping up to the target voltage level with the external supply (rather than turning it on and off at full voltage), right?

Would this address your concerns and enable us to power the supply rail with an external supply?

Thanks!
Cody