0 220V Led Flasher Circuit

This circuit is similar to Two Transistor LED Flasher but the only difference is it uses 220VAC as the source instead of a battery. The circuit is powered by a transformer-less ac-dc converter using a capacitor. Capacitor Cx limits the total current to 40mA and resistor Rx lessens the inrush current. Bridge diode D and capacitor C1 rectify and smoothen the DC output.
flasher schematic
Part List:
Rx - 470 kilo ohms 1/2W
R1 - 390 ohms 1/4W
R2 - 56 kilo ohms 1/4W
Cx - 470nF capacitor rated 350V minimum (use 1000V)
C1 - 100uF electrolytic capacitor rated 35V
C2 - see the capacitor vs time table
Q - 2N4401, 2N2222A and similar NPN transistor
LED - 3mm or 5mm RED or any low power LED
NPN transistor pins
LED pinout
Below is the table originally from the Two Transistor LED Flasher. The actual result in using the circuit above may vary a little but it is still a good approximation. T is the duration where the light of any LED will last or the time the LED is on.
cap C2 vs time table

Note: The circuit is powered directly to AC source thus can cause electrocution when touched. Do not build the circuit if you are new to electronics or don't have any idea at all. I suggest build the low voltage flashers below.

Other Flashers, low voltage and safer to build:
Lamp Flasher using FET - high current Flasher powered by 12V
Two transistors Flasher - very simple led flasher
1.5V flasher - powered by 1.5V flasher
Bulb Flasher
Flasher using 555 IC - flasher using lots of LEDs


Post a Comment