how can I get 5V DC from 220V AC? without transformrer

alanlai1 · ‎2003-10-21

Posted on October 21, 2003 at 09:07

alanlai1 · ‎2003-10-20

Posted on October 21, 2003 at 07:09

I am now doing a project, ( AC power, Thermal Controller )

Only allow to use mcu + thermal resistor + heater. I feel headache that the voltage supply is AC, how can I get 5V DC from 220V AC? without transformrer.

Is it possible to use discrete components to do it?

zener diode? cap? resistor?

because the project is cost-down approach.

marco32 · ‎2003-10-21

Posted on October 21, 2003 at 09:07

Look at Application Note AN392 from ST6

(Microcontroller and triacs on the 110/240V mains)