Hi,
In this thread, there is talk of problems with UCC28070...
https://www.eevblog.com/forum/projects/bridgeless-pfc-controller/..post #5 mentions many people having trouble with UCC28070.
Also, in this thread, an Engineer says he used UCC28070 with a Hall sensor instead of a CST.
https://www.edaboard.com/threads/how-do-you-build-an-offline-isolated-multiphase-power-supply.309323/(Post #20)
Also, the following thread in posts #3 and #6 suggests UCC28070 problems..
https://www.eevblog.com/forum/projects/looking-for-a-pfc-preregulator-in-the-~1-5kw-range/Also, i had 2 of them blow up on me from ESD like damage.
I actually think there is some issue with the use of the CST with the UCC28070, and that biasing resistors, and ramp circuits, (as in the app notes) are needed to "manage" the connection of the CST to the UCC28070 otherwise, problems can ensue.
The thing is, the calculation of values for the biasing resistors is not given.
Obviously they have got it right in their demo board, but thats for that specific case only.
Without access to the ti.com forum myself..(you need a corporate email address to get on the texas forum) ..does anyone know of issues with the UCC28070?