Is there any IC which works from 15VDC to 265 VDC DC to DC converter wherein my output is 2W(12V)? i need an isolated power supply.

 

I started to respond but realized I had on idea of what you needed. My take is you need is 15V DC to 12V DC,output isolated from input ? Now I get it just like you said; a wide range DC input to 12 V DC. This a thought not a suggestion; here is a switching ps 100-240 V ac in,12V @ 300ma out, if you tapped in after ac rectification might cover 75-260 V DC. how low you could go ,dont know. It will be hard to find off the shelf. Best wate for a better answer.

 

Did you really mean 265VDC?

 

Can u pls brief the answer.

 

Did you really mean 265VDC?

yes input range is from 15VDC to 265VDC

 

That is a very wide range for a converter. The input range of typical DC-DC converters span 2:1 or 3:1. I would surprised if you could find an efficient 2W converter with that input range.

(* jcl *)

 

I mis stated thought: connect DC supply to input of switching PS [ check input with low voltage ohm meter first. Open ckt probabily means a diode bridge input which will work ] With a 100-240 V AC input PS ,12V DC out,it took 72V DC to start, on dropping V gradually output held at 12V down to 15 V DC input. Might use two inverters, one for low range and one for high.