Bi-color LED Flasher Circuit

This transformerless mains power supply circuit makes it possible for flashing of a Bi-color 100 LED string, in an alternately switching red, green impression.

The suggested circuit works extremely well as a Bi-color LED flasher, for developing an alternate red, green flashing effect over a string of 100 LEDs.


bicolor LED 2 PIN-5mm Bi-color LED diode

bicolor LED 2 PIN-5mm Bi-color LED diode

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B-color LEDs are available in 3-pin and 2-pin categories, in our activity we use the 2-pin Bi-color LED option for making things sleek and a lot effectual.

2 Pin Bi-Color LED Flasher Circuit 100 LEDs red and green

2 Pin Bi-Color LED Flasher Circuit 100 LEDs red and green

Viewing the layout presented above, we are able to observe a clear-cut design utilizing a push-pull clock generator IC 4047.

The IC is designed for producing an alternately switching pair of outputs, from the presented pinout#10 and 11 of the IC.

The frequency of such alternately performing outputs could be pair by suitably altering the pot P1 and by picking out the preferred spectrum with C1.

The switching outputs can be found set up with two oppositely wired SCRs, that happen to be subsequently connected with the Bi-color LED string across the mains input by means of a lowering high voltage capacitor C3.

The circuit additionally includes a transformerless power supply stage which contains C2, D1, C4, Z1, for operating the IC with the desired low voltage DC.

When ever the offered 2 pin Bi-color LED flasher circuit is activated, the IC begins oscillating at the fixed rate across its pin#10 and pin#11 alternately, operating the SCRs at the identical switching rate.

The SCRs react to these pulses and perform correspondingly, making it possible for the Bi-color LED string to light up by means of an alternately green and red color flashing outcome.

Parts list for the above discussed Bi-color LED flasher

R1, R2, R3 = 1K

C1, C4 = 100uF 25V

C2, C3 = 0.33uF/400V

Z1 = 12V 1 watt zener

D1 = 1N4007 diode

SCRs = 2nos BT169G

LEDs = 100nos, of 2pin, Hi-bright RED, Green Bi-color LEDs