We have an SMPS that was designed by a third party. The controller, VIPER100, has gone obsolete. ST don't do any sort of direct replacement, but other manufacturers do similar devices or at least controllers that use an external FET that would enable us to get the same power output.
Is it possible to use the existing transformer with a different controller? I appreciate, we'd likely have to tweak the opto feedback part of the circuit and it we'd have to ensure that the winding that fed the controller gave the correct output for a new controller.
Other than that, is it a sensible idea to just try and replace the controller, but use the existing transformer, or is better to have a new design done from scratch?
I know the basic theory how these off-line controllers work, I've done loads of inductor based dc/dc converter designs, but have essentially no experience in transformer design.