Hi,
I use controller UCC256304 for power supply 24V/350W
design input range 240V-390VDC
i can turn it startup at full load, output working stable. but then about 25 second after first startup otuput power go down --> restartup output working about 1 second --> restartup output working about 1 second --> then no output power.
I measure current of resonance winding when it fail output is overshort current switching. but in first startup i measure current is belower and stable.
how I can fix it?, and how many reason make it fail output power?
thanks!