Hi, i was trying to do a power supply (12V@0,5A) with a Buck Configuration.
But here is the issue: Doesn't work when my input is equal to 220V. At 127V works ok.
There is a trouble with DZ3, the voltage never reachs to 5v1, then Vref can't go to 2.5V.
the schematics is attachedBuck Converter.pdf.