I am designing an offline flyback converter using UC3844 pwm ic with output 5V/5A specification. But initially with no-load, the supply voltage is swinging between 10-16v meaning it is switching on and off continuously that is happening because the auxiliary winding is not able to provide enough current at no-load. It works fine when on load as it is supposed to be. I have increased the no. of turns to have increased voltage but to no avail.
Current Transformer spec: 63 turns 30swg, 1strand(pri) 3 turns 22swg, 5 strand(sec) 16 turns 35 swg, 1strand (aux)
Another person having this problem, but no solution posted. http://www.eevblog.com/forum/projects/uc3844-flyback-converter-startup-problem/ Any help would be appreciated.