Actually I need to design a SMPS(i/p 4.5-6V dc@ 800mA & o/p 25-28V dc@ 120mA) without using Transformer. I have only a bit of bookish knowledge on PWM, SMPS & as well as Bost & Buck converter & some hand on experiance on Linear power supply.
I request every member of this forum to help me for designing such type of SMPS both theoritically & practically. If any one have practical idea about this ckt. Plz mention the ckt. diagram & parts list(which will be available in India).

Looking for response.

 

Hello,

Did you already have a look at the MAX668 and MAX669 ?
See datasheet.

Greetings,
Bertus

 

Thanx. I am checking. Again thanx for sharing.