can the LT3799 be used as a dc converter with ac input?
Apparently, a TM PFC regulator in voltage mode can convert ac to dc through a flyback operation- pretty similar to LED circuit but the pure dc regulator must regulate the output voltage.
In the LTSPICE model, it does not come out to be obvious. Yet, the isolated aux winding that feeds the Vcc power of the chip looks pretty good DC of course with little load.
In this sense, it is acting as a primary side controlled isolated regulator. Just need it to be voltage in my application.