Lt8302 not working on load

[Arpit Gupta]

THE LT8302 FLYBACK CONVERTER that i designed is not working on load
it was designed for 3 multiple outputs of 12 v
ON no load the all the output shows 13.24 V
But as soon as even at very low loads of milliAmps the voltage disappears

what could be the reason?

 

[D.A.(Tony)Stewart]

Most likely layout problems of line inductance, high ESR secondary caps or lack of attention to details.

"the basics of current mode DC/DC conversion will not be discussed here; instead, the reader is referred to the detailed treatment in Application Note 19, or in texts such as Abraham Pressman’s Switching Power Supply Design"