Ijaz thanks for educating me. valuable information. as i mention you at the moment i am experimenting so can and using the PC power supply but once i have gone through then i will have to have a design to be used in a possible commercial product. as can go with a book to understand the basics but i think i don't have time as i am also a full time software engineer. TopSwitch is a good suggestion, i think i need such suggestions.


Shahzad