Simple LED Strobe Light Circuit

This guide shows you how to build a flashing LED light strobe light using a common chip called the IC 555 .

Some knobs and resistors control how fast the light flashes and how bright it is.

Another resistor controls how much power goes to the LEDs.

This project uses a special switch that can handle a lot of power.

But you can also use other similar switches.

You can adjust this circuit to work with different types, colors and numbers of LEDs by changing one resistor value.

In this example, we use 36 white LEDs arranged in 3 rows of 12.

Important: Make sure the voltage from your power supply is high enough to handle all the LEDs connected together.

What is a LED Strobe Light Circuit:

A LED strobe light circuit is an electronic circuit that controls the flashing or strobing of Light Emitting Diodes LEDs.

Strobe lights are characterized by their rapid intermittent bursts of light and they find applications in various fields including entertainment, warning systems, and special effects

Circuit Diagram:

Parts List:

Circuit Construction:

The construction of this LED strobe light circuit can be understood with the following points:-

Connect the 555 IC:

• Connect the power supply to pin 8 of the IC 555 and ground to pin 1.
• Connect pins 2 and 6 together.

Set Up Components:

• Connect a capacitor C1 between pins 2 and 6.
• Connect a resistor R2 from pin 7 to pin 6.
• Connect another resistor R1 from pin 6 to pin 2.
• Connect a variable resistor P1 from pin 6 to ground.
• Connect a resistor R3 from pin 7 to the positive side of the LED array.

Connect LEDs:

• Connect the negative side of the LED array to ground.
• Connect the positive side of the LED array to pin 3 of the 555 IC through the power switch.

Power Switch Connection:

• Connect the drain pin of the MOSFET to the positive power supply.
• Connect the source pin of the MOSFET to pin 3 of the 555 IC.

Adjustable Components:

• Adjust P1 to set the desired frequency of the strobe.
• Adjust R1 to control the duration of light burst.
• Adjust R3 to regulate the current supplied to the LEDs.

Testing:

• Power up the circuit and observe the LED strobe effect.
• Ensure that the voltage drops across the series connected LEDs are within the specified limit.

Formulas and Calculations:

LED Current Calculation:

The current flowing through the LEDs is determined by the resistor R3.

Use ohms Law to calculate the current I_LED​

I_LED = V_R3 / R3

where,

• V_R3​ is the voltage across R3, which can be calculated as:

V_R3 = V_supply−V_LED

where,

• V_supply is the supply voltage, and
• V_LED is the combined voltage drop across the series connected LEDs.

LED Series Voltage Calculation:

• Ensure that the sum of the voltage drops across the series connected LEDs V_LED is always less than the supply voltage V_supply.

Important Notes:

• As mentioned earlier be cautious about potential health risks associated with rapid flashes of light.
• Modify the circuit based on different LED types, colors and quantities by adjusting the value of R3.
• Ensure the power supply voltage matches the requirements of the components used.

Conclusion

If you plan to build or experiment with a LED strobe light circuit, it is essential to consider safety precautions especially if you are working with high intensity LEDs or connecting the circuit to a power source.

Additionally, understanding the specific requirements of your application and the characteristics of the LEDs you are using will help you design an effective and reliable strobe light circuit.

References

LED strobe lighting for machine vision inspection

Strobe light