LED Strobe Light Circuit

In this project let us develop an LED Strobe light circuit using the popular 555 timer IC. A strobe light or a stroboscopic lamp is one which can produce regular flashes of light. We are designing this circuit using a 555 timer for setting the delay between each flash and a high power LED light as the source of light. At the end of this project we will learn how to use 555 timers in monostable mode and how to calculate the delay for such a circuit.

 

Components Required:

The components required for this project is listed below

1. 555 Timer
2. High Power LED
3. 10k Resistor
4. 0.01uF,0.1uF Capacitor
5. 10M Potentiometer (or 1M, 2M Resistors)
6. Breadboard
7. Connecting Wires
8. 9V Battery

 

Strobe Light Circuit Diagram and Explanation:

The complete circuit diagram is shown in the above image. You can either build them on a breadboard or solder them to a Perf Board. The explanation of the circuit is given below.

 

Circuit Explanation:

The heart of the strobe light circuit  is the 555 Timer which is operating in Monostable mode. The 555 Timer can operate in 3 different modes such as Astable, Monostable and Bistable mode.  All these three modes produce three different types of pulses which can controlled at a particular point. The Monostable mode produces pulses whose high state time can be set by giving a trigger at pin 2. The output(pin 3) of the 555 IC normally stays low, whenever the pin 2 is triggered the pin 3 will go high for a specific interval of time.

This delay can be controlled by changing the values of Resistor (Potentiometer) and the capacitor (C2) shown in the circuit. The formulae to calculate the delay is shown below

T=1.1×R×C

Where, resistance R is in ohms, Capacitance C is in Farads and Time is in seconds. I have used the resistor value as 1M ohm and capacitor value as 0.1uF to produce a delay of about 0.1 second.  You can change the delay by varying the potentiometer.

 

Circuit Simulation:

In order to further understand the working of this project. Let us try simulating the project using the Proteus software. Using the help of a DSO in Proteus we can visualize the pluses produced by the 555 Timer. You can download the Proteus design file from here.

After downloading click on play button and you should see the graph as shown in the below image.

You can vary the resistor R2 and notice the Pulses getting varied based on the resistor value. This variation will affect how fast the LED turns on and off. The waveform is enlarged in the image below.

 

Working:

Once the connections are given simply power the circuit using a 9V battery. You should notice your LED flashing. If it looks stable, it means that it is flashing so fast that it is not visible to the naked eye.  So gradually adjust the potentiometer to vary how fast it should flash. You can watch the video below for complete working of the project.

 

That is it we have a working of LED Strobe light setup. Hope you enjoyed the project and got it working, if not post your problems in the comment section and I will help you out.