How to convert AC voltages in specific voltages.?

[newtonisback]

Hello there,
I want to design a SMPS and that is all about AC to DC converter.
Now,
My requirement is
Input = 20-260 VAC or 38- 366 VDC

Output = 15V or 25 V @ 4W power....

So is there any transformer or circuit which can help me getting this specific value...???

Is any one there who knows???

 

[kappa_am]

hi,
use fly-back configuration.
Good Luck

 

[newtonisback]

Thanks Kappa_am,
I used flyback topology,
Specifications are as mentioned below.

Input range: 18-265VAC
Output1: 25VDC@110mA
Output2: -15VDC@30mA
Output1 & Output2 has common Ground1.
Output3: 13VDC@35mA
Output4: -13VDC@35mA
Output3 & Output4 has common Ground2.

Ground1 and Ground2 are Isolated from each other, & also isolated from Primary.

Could you suggest me best design or schematic??

 

[kappa_am]

unfortunately, I have any schematic with these specifics.
It is apparent you need a transformer with one primary winding and 3 secondary windings that one of them has middle terminal and ofcourse a start winding. a feed-back network is another main part of the circuit. I think searching google and looking at some schematic gives you a valuable sight.
many books are also publishd that discuss switching power supplies like:
Demystifying Switching Power Supplies by: Mack
Switching Power Supply Design byressman
Troubleshooting Switching Power Converters - A Hands-on Guide By: Manikata
however, it is a custom design, and you have to design your own circuit on your own.

Good Luck