Transformerless power supply for PIC

[hongphuc118]

I want to use transformerless power supply for PIC.
Can I use this schematic for it?

 

[mister_rf]

Re: Power supply for PIC

**broken link removed**


Now here is the problem that is very DANGEROUS, and should be looked into. Never use this circuit!


Transformers and switching supplies isolate mains power from the output power. The limits in these supplies keeps the power to a safe level. But since this is a non-isolated solution, we get the mains supply to be common with the power supply line , which possible could be very dangerous if circuit is exposed.

 

[jpanhalt]

Re: Power supply for PIC

The simple answer is yes, transformerless supplies can be used to power PIC's. Microchip has an application note to that effect: https://ww1.microchip.com/downloads/en/AppNotes/00954A.pdf

However, I would not do it. There are just to many safer and still cheap ways to do it, as with a simple wall wart. Here is a more lengthy discussion of the pros and cons of the circuit in AN954 referenced above:
https://www.microchip.com/forums/m200665-print.aspx

John