Many electronics circuits and projects for learning in simple ways.

Two way 12 LED running lights using CD4017 and NE555

This Two way LED running lights to use for beautiful, this circuit uses 12 LED lamps, arranged in 2 rows, each row of 6 leds. A green one and a red one, alternatively. use a different color for this.

Technical information
-The power supply of 6-12 VDC.
-Power consumption is about 12 mA maximum
-Have the speed of the flashing.
-PCB dimensions: 2.80 x 1.77 inchs.

How it works
This circuit have 2 IC, IC1-555 is frequency generator, by this frequency can adjust at 10K-potentiometer output of IC1 through R-100 ohms in to pin 14 of IC-4017. The IC-4017 is Decade counter with 10 decoded outputs IC IC.


Which its output glowing will slide down each position, by begin from output at 1 is pin 3, 2, 4, 7, 10, 1, 5, 6, 9 and 11 in sequence.
When it to pin 11 the output light will back to pin 3 and continue to glow in sequence each step, by the signal from IC-555 in circuit. Which we can set output at 6 position then backward glow, by notice at the IC output pin as LED can reverse run. The 1N4148-Diodes to protects voltage from output to same LED point.

How to builds.
The circuit assembling is shown in Figure 2 should begin low to high parts sequence, for Beautiful and simple. By begin with diode, resistors and higher. And the parts have different polarity such as Diode, Electrolytic Capacitors and transistors etc.

The components layout on PCB
Figure 2 The circuit assembling as components layout on PCB

To apply a power supply size 9-volts to circuit will see LED glow continue step to step run go and back. And can adjust speed up by adjust at 10K-potentiometer.

This circuit uses power from 9-12-volts Therefore can install in the car using voltage 12-volts.

The component list.
R2—————500 ohm
R3—————100 ohm
R4—————470 ohm
Trimmer Potentiometer
VR1————-10K or 103
Electrolytic Capacttors
IC1————–NE555 Timer IC
IC2————–CD4017- Decade counter with 10 decoded outputs IC
D1-D8———–1N4148__ 75V 150mA Diodes

This Post Has 7 Comments

  1. what should be the working voltage for those 2 electrolytic capacitor.pls provide it

  2. Hi,Abhishek
    Thanks for your feedback.
    In normal we use 2 times of a supply voltage.
    or around 25V but if same cost I alway use 50V or 63V.

    I am sorry for late reply.

  3. thanks momename

  4. I want to connect 100 led at outpin of ic 4017 using relay or scr connecting with output pin can it posible. Plz give suggestion I am waiting for your prompt responce.

  5. @ANN:AH…Please use a 1N4148 switching Diode…Many Thanks From MROHM1970!!!!

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