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LED Chaser Circuit

This is the circuit of a simple LED chaser. The LEDs lights one by one for a period of 1second and the cycle repeats giving the running light appearance. The circuit uses two ICs (one is 555) to drive the LEDs.

IC1 (NE555) is the popular timer IC wired in the Astable Multivibrator mode. Resistors R1, VR1 and capacitor C1 act as the timing components and the output pulses are available from the output pin 3 of IC1. These pulses are given to the input pin 14 of the Johnson decade counter IC CD4017. Out of the 10 outputs of IC2, eight outputs are used to drive the LEDs. The ninth output pin 9 is connected to the reset pin 15 to stop the counting. So that the cycle repeats. With the value of C1, each LED remains on for 1second. When one LED turns off, the second on turns on. This cycle repeats giving the running light appearance. Resistor R3 keeps the input pin 14 of IC2 low after each pulse.VR1 adjusts the speed of LED chasing.

LED Chaser Circuit

15 Comments

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  • Jim Keith

    R2 is 100 ohms.
    Higher value may be used to make LEDs dimmer and increase battery life.

    • Danilo Mortel

      Hi there Mohankumar, reference to LED Chaser Circuit what type of capacitors are c1 and c2, ceramic disc, mica or polyester? Kindly provide the details of c1 and c2. Many kind regards.

  • sathyanarayanan

    MY DEAR FRIEND.
    this project very useful in many palace
    i want one request this project 230vac & rechargeable battery two wave use this project? R2 IS 100 OHMS OR 100K?
    PLS SEND THE EMAIL I AM INTRESTED TO LORD OF WORKING ELECTRONIC PROJECTS.

    THANKS

    BEST REGARDS
    SATHYANARAYANAN.

  • DAC

    I just wanted to ask about the resistance of R2 is it 100K or just 100 ohms ?
    Thanks in advance… 🙂

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