SMPS controller for a non isolated PSU design

[tomicode]

Hello,
I am designing an ATmega based wireless light switch. For my test layouts I used the HLK-PM01 PSU, but having it completely enclosed I think it is time to design a SMPS, but a non-isolated one. First of all, I know the risks of non-isolated power supplies.

So my project requires a 5V 100mA rail and my question is related to choosing a controller chip. For example I found at ti.com a buck converter circuit http://www.ti.com/lit/ug/tidt015/tidt015.pdf and seems fine, but the typical application schematic for the UCC28710D: http://www.ti.com/lit/ds/symlink/ucc28710.pdf supplies only an isolated power supply reference and many other controllers seems to do the same. Now to my question, probably a silly one: How can I adopt other controller chips from an isolated layout to a non-isolated?

Best regards,
TomiCode

[T3sl4co1l]

Even if you don't need isolation, it can be worth using a normal isolation transformer because they're off-the-shelf.

The price is awful though.  You can buy a ready-made module for $10, or all the parts you need for this for a little more than $10.

Not that single-quantity pricing is at all meaningful.

You may be interested in a high voltage buck, like these things,
https://www.monolithicpower.com/en/mp163c.html

Tim