LED Flasher Circuit Design - 

Here the led flasher circuit, we design for you, it is a very simple and cheap led flasher circuit. We don’t add power supply circuit, with this led flasher circuit.

For power supply circuit, you can use 12v battery or DC-12v adapter circuit. The schematic of LED flasher circuit design along with the PCB layout can be seen below.

Transistor Pin Out -

We everybody knows that, all kind of transistor contain 3 legs. And all 3 legs have 3 different names. To make this led flasher circuit connection,

1st we need to know about the pin out of this BD-139 transistor.


BD 139 –  BD 139 is an NPN transistor. If we count its leg from left side, then 1st leg “Emitter” 2nd leg “Collector” and 3rd leg “Base”

Connect Transistor with Circuit -

 To make this led flasher circuit, we are using transistor. 1st we connect, one transistor emitter leg with other transistor emitter leg.

Now we need to connect other component with the circuit.

Connect Resistor with Circuit -

 Now we connect 10 KΩ resistors with led flasher circuit. We connect this resistor one side empty terminal. Then we need to connect,

other two resistor empty terminal with Base leg of transistor.

Connect Capacitor with Circuit - 

To flash in a rhythm, we are using 47µf/ 25v capacitor. We connect one capacitor positive leg with one transistor Collector leg and connect capacitor negative leg with other transistor Base leg.

In the same way, we connect another capacitor positive leg with another transistor Collector leg and connect capacitor negative leg with other transistor Base leg.

 Connect LED Light with Circuit - 

Since, it’s a led flasher circuit, for that we might need led light. For better effect, we are using two different color led light. We can use maximum 24 pieces leg light to make this flasher light. 1st we make a series connection, so that the light can operate using DC-12v power supply.

Then we connect two color led light positive leg with common leg of 10k resistor. Now we connect, this two difference color led negative leg with Collector leg of two different transistors.

Connect Power Supply with Circuit - 

To operate this led flasher circuit, we might need power source. We know that, for power source we are using DC-12v power supply. We connect this power supply positive cable with positive leg of LED light and connect DC-12v negative cable with Emitter leg of transistor.

Soldering & Cleaning Amplifier Circuit - 

It’s the time to soldering and cut-off all extra leg of electronics component. Now we solder all component leg carefully and to make sure we need to check all of them for several times. We also remember that, there should not be any kind of short circuit connection. For perfect inquiry,

we should use liquid PCB cleaner to wash PCBs.

 Thanks to JLCPCB, for sponsor us such a quality PCB board.

Enjoy the Effect of LED Light -

Our circuit is now completely ready for use. Now just plug-in power and enjoy the awesome effect of this led light circuit. For better result,

you can use this circuit, in a dark place.