Dc/dc with uc3842

[gggbg]

Hello! I need a little help with my DC-DC project. I have to make DC-DC converter : Vin =22-32V ; Vout =9-19V; Iout=5A. The schematic is made by myself. Everything is working fine, but I can’t cope with the significant pulse-width jitter I have. Can anyone help me with solving with this problem?

 

[Bettecher]

I think that your main problem is the mosfet driver and the short circuit protection.
In order to solve your problems, I suggest you to change your design to flyback mode and follow the basic schematic at the IC’s datasheet.

Regards,

Marcos Bettecher

 

[gggbg]

It is a good idea, but the flyback transformer would be with big size, and I have no enough room for it. Don't you thing Bettecher your attachment is a forward converter?

 

[Bettecher]

gggbg,

The attachment was just an example.
By removing one diode and the coil at the output filter, you will work as flyback mode.

Regards,

Marcos Bettecher