standby power

[tekman11]

Hi wall warts have become smaller over the years so I took one apart.
the input is rectified then feed into some sort of fly back SMPS which provides a output voltage.

Does anyone know of a tutorial which  discuss this subject?
They come in isolated and non isolated flavors, under what situation would a isolated version be used?
Is  input protection on the AC side (MOV or fuses) required?

thanks

[Zero999]

A wall wart should always be isolated, unless the insulation on the equipment and cabling is rated for mains voltages.

Here's a link with more information on switched mode power supplies.
http://www.nxp.com/documents/application_note/APPCHP2.pdf