In this article, we will explore various LED Running Lights Circuits, also known as LED Knight Rider Circuits. These circuits can be applied to vehicles such as cars, motorcycles, and bikes, enhancing their visual appeal for onlookers.
We have designed four distinct LED Running Lights Circuits using straightforward components. In the initial circuit, we have incorporated Flashing LEDs utilizing a transistor-based Astable Multivibrator.
The second circuit features Chasing LEDs and is centered around the IC CD4017. Here, the LEDs illuminate sequentially, one after the other. The CD4017 is also utilized in the third circuit, where the LEDs display a unique pattern—a two-way running sequence.
In the final circuit, the LEDs initially move in one direction and then reverse their course, resembling a pendulum’s back-and-forth motion.
These circuits serve both aesthetic and practical purposes. They can enhance the visual appeal of your vehicle and prove valuable in emergencies, such as when your car breaks down and you require assistance.
We will delve into the specifics of each of these circuits, including their circuit layout and component requirements.
Outline
- Simple LED Running Light Circuit (Flashing LEDs)
- Circuit Diagram
- Components Required
- Working of the Project
- LED Chaser Circuit using CD4017 and 555
- Circuit Diagram
- Components Required
- Working of the Project
- Two Way Running LEDs with 11 LEDs, CD4017 and 555 Timer IC
- Circuit Diagram
- Components Required
- Working of the Project
- Circuit Diagram of LED Knight Rider Circuit Diagram:
- Components Required for the Circuit:
- Description:
Simple LED Running Light Circuit (Flashing LEDs)
In this project, we have designed a simple Flashing LED Circuit. We have used two sets of LEDs (3 on one side and 3 on the other) that will be turned on alternatively so that the outcome is a bright flashing LEDs.
Circuit Diagram
Components Required
- 2 x 2N2222A (NPN Transistor)
- 2 x 22µF – 50V Capacitor (Polarised)
- 2 x 46 KΩ Resistor (1/4 Watt)
- 6 x 8mm Bright White LED
- 12V Power Supply
- Connecting Wires
- Breadboard
Working of the Project
The underlying principle of this circuit is based on a straightforward Astable or Free Running Multivibrator, as evident from the circuit diagram. When the circuit is powered on, one transistor operates in the ON state (Saturation), while the other remains OFF (Cutoff).
During the ON state of Q1 (when Q1 is in Saturation), Capacitor C2 charges via the connected series of LEDs. The LEDs illuminate as they are positioned within the current path.
Simultaneously, Capacitor C1 begins discharging, causing transistor Q2 to turn off (the negative plate connects to the base of Q2). Once the time constant C1R1 elapses, C1 becomes fully discharged and initiates charging through R1.
However, this charging process occurs in the opposite direction. As C1 charges, it accumulates sufficient voltage (0.7V) to activate transistor Q2. Subsequently, Capacitor C2 begins discharging through Q2.
When the plate of Capacitor C2, linked to the base of transistor Q1, turns negative, transistor Q1 and the associated pair of LEDs are switched off.
At this point, Capacitor C1 commences charging through the series of LEDs it is connected to (via the base of Q2). These LEDs illuminate as they are part of the current path.
Following this, Capacitor C2 undergoes discharge, and once it is completely discharged, it starts recharging through R2. As the voltage within Capacitor C2 reaches 0.7V, it triggers the ON state of transistor Q1. The circuit then repeats this process as described earlier.
LED Chaser Circuit using CD4017 and 555
The second project in the LED Knight Rider Series is an LED Chaser circuit using CD4017 Decade Counter and 555 Timer IC. We will see the circuit diagram, components used and the working of this project
Circuit Diagram
Components Required
- 1 x CD4017 Decade Counter IC
- 1 x 555 Timer IC
- 1 x 18 KΩ Resistor (1/4 Watt)
- 1 x 2.2 KΩ Resistor (1/4 Watt)
- 1 x 100 KΩ Potentiometer
- 1 x 1 µF – 50V Capacitor (Polarised)
- 1 x 0.1 nF Ceramic Disc Capacitor (100 pF code 101)
- 10 x 8mm Bright White LEDs
- Connecting Wires
- 5V Power Supply
- Breadboard
Working of the Project
In this project, we’ve crafted a basic LED Chaser Circuit, where the LEDs sequentially illuminate, creating the visually appealing effect of one LED seemingly chasing the other. Now, let’s delve into the operational details of this project.
The circuit schematic reveals two distinct sections: the 555 Timer and the CD4017 Decade Counter IC integrated with the LEDs. In this setup, we’ve configured the 555 Timer IC as an Astable Multivibrator, operating in pulse generation mode. The frequency of the generated pulse is modulated by the values of the components R1 (2.2 K), R2 (18 K), VR1 (100 K), and C1 (1F). The 100 K POT (potentiometer) can be precisely adjusted to control the pulse’s frequency.
The CD4017 Decade Counter IC receives this pulse at its Clock Input pin. Understanding the CD4017’s operation, we observe that for each clock pulse it receives, the count increments by one, leading to the corresponding output pin turning HIGH. Given that it’s a decade counter, we obtain a count of 10. Since we’ve connected bright white LEDs to the output pins, each LED illuminates when its associated pin goes HIGH.
After 10 clock pulses, the count resets, starting anew. When the LEDs are arranged in a circular pattern, this creates the visually captivating effect commonly known as the Chasing LED effect.
Two Way Running LEDs with 11 LEDs, CD4017 and 555 Timer IC
This circuit presents another iteration of a running LED configuration. The key distinction between this circuit and the earlier one lies in the operational mode: in the previous circuit, LEDs ran in a unidirectional manner, while in this circuit, the LEDs exhibit a bidirectional running pattern.
Circuit Diagram
Components Required
- 1 x CD4017 Decade Counter IC
- 1 x 555 Timer IC
- 1 x 18 KΩ Resistor (1/4 Watt)
- 1 x 2.2 KΩ Resistor (1/4 Watt)
- 1 x 470 Ω Resistor (1/4 Watt)
- 1 x 100 KΩ Potentiometer
- 1 x 1 µF – 50V Capacitor (Polarised)
- 1 x 0.1 nF Ceramic Disc Capacitor (100 pF code 101)
- 8 x 1N4007 PN Junction Diodes
- 11 x 8mm Bright White LEDs
- Connecting Wires
- 12V Power Supply
- Breadboard
Working of the Project
The Two Way Running LEDs project operates in a manner similar to the LED Chaser Circuit, albeit with a distinct LED arrangement. Let’s now explore the functionality of this project.
The 555 Timer generates a pulse signal, serving as the clock input for the CD4017 Counter (this process is akin to the one explained in the previous circuit). Initially, LED6, linked to CD4017’s Q0, is the first to illuminate.
Following this, LED5 and LED7, associated with CD4017’s Q1, illuminate. This pattern of connections continues in accordance with the circuit diagram until reaching Q5, where LED1 and LED11 are activated. Up to this point, the LED lights exhibit a unidirectional illumination pattern.
To achieve the two-way lighting effect for the LEDs, connections are made such that Q6 corresponds to LED2 and LED10, Q7 corresponds to LED3 and LED9, and so forth.
The final effect will be a Two Way Running LEDs and the sequence will be as follows: LED6 (Q0), LED5 – LED7 (Q1), LED4 – LED8 (Q2), LED3 – LED9 (Q3), LED2 – LED10 (Q4), LED1 – LED11(Q5) for one way and followed by LED2 – LED10 (Q6), LED3 – LED9 (Q7), LED4 – LED8 (Q8), LED5 – LED7 (Q9).
Circuit Diagram of LED Knight Rider Circuit Diagram:
Components Required for the Circuit:
- IC
- NE555 – 1
- CD4017 – 2
- Resistor
- R1 (1K) – 1
- R2 (100K) – 1
- R3 (10K) – 1
- VR1 (100K) – 1
- C2, C1 (.1uf) – 2
- D1-D9 (1N4148) – 9
- Transistor (BC547) – 1
- LED1-LED9 – 9
Description:
To comprehend the operational configuration of the circuit, it is essential to acquaint yourself with each individual pin.
This integrated circuit (IC) comprises a total of 16 pins. Among these, three pins serve as input pins, ten are designated for output functions, one is assigned to ground, one is for power supply, and the remaining one is reserved for the Carry out function. The pin diagram of the CD4017 IC is illustrated below for reference.
1. Input Pin:
- Reset Pin (Pin 15) — This pin resets the counter to zero. If you want the counter to start counting from the third pin, you’ll need to connect the fourth output to the 15 pin. As a result, after every third output, the counting resets to zero.
- Clock Pin (Pin 14) — When the IC’s pin 14 is set to high, the output is supplied. For example, when the clock’s first pulse arrives, pin 3 will produce output, and when the next clock pulse arrives, pin 2 will supply output, and so on. It will restart from Q0 output after 10 clock pulses.
- Clock Inhibit Pin (Pin 13) — This pin is used to toggle the counter between ON and OFF states. If you want to turn off the counter, pin 13 should be set to the highest state. If it is in the high state, it will ignore the clock pulse regardless of how many times you press the switch, implying that the count will not advance. In our circuit, pin 13 is grounded.
2. Output Pin (Pin Q0 – Q9)
In the sequential manner the output is received from these pins. Like pin 3 will give you output for the first pulse and so on.
3. Ground Pin (Pin 8) and Supply Pin (Pin 16)
For the working of the IC pin 8 provide ground while power supply is provided by pin16.
4. Carryout Pin (Pin 12)
By employing this pin, you can interconnect one or more CD4017 ICs. For instance, if you wish to add another CD4017, simply connect pin 12 to the input clock of the subsequent IC. The carry pin of the initial CD4017 is linked similarly to the second clock input, and this pattern continues for subsequent CD4017s, as depicted in the circuit diagram.
The circuit is constructed around two integrated circuits (ICs): the NE555 and the CD4017, alongside a few additional components. Within this design, the IC 555 timer functions as an astable oscillator.
The CD4017, a CMOS counter/driver IC, is utilized. When triggered by a clock pulse, it sequentially activates all ten of its output pins. This IC is well-known for its versatility and finds application in various projects, such as Light Chasers and Matrix Displays.
In this circuit, the NE555 IC operates in astable mode to generate a clock pulse for the circuit. This pulse is utilized to produce an oscillating waveform at the output pin 3 of IC1.
By the help of VR1 the speed of oscillation can be alter. 555 timer oscillation frequency can be calculated by-
f=1. 44/(R1+2* (VR1) *C1)
Because we’re using two decade counters, we’ll start counting from 0 to 16 in this circuit. IC2 in the circuit counts from 0 to 9, while IC3 does the rest of the counting with the help of diodes.
Upon applying power to the 555 timer, pin 3 of IC1, the output, is linked to pin 14 of the CD4017, which serves as a decade counter. This connection initiates the generation of a clock pulse, enabling IC2 to operate. The CD4017 commences its counting sequence from zero once it receives the clock input, owing to its built-in counter functionality.
Subsequently, as pin 14 rises to a high state, it sequentially advances through each of its output pins. For instance, at the initial stage, output Q0 emerges at pin 3, illuminating LED1, while LED2 lights up via pin 4, and so forth.
Upon reaching pin 11, which represents the ninth output, it generates a brief high signal that is directed to pin 13 (clock inhibit). If pin 14 is in a high state, it disregards the clock pulse, halting the counting process in IC2.
Consequently, pin 15 of IC3 becomes low, given that the BC547 transistor was previously in a high state. This momentarily resets pin 15 of IC3 to a low state due to this low signal, causing IC3’s output to continue counting from Q0 (pin 3) in a sequential manner.
Upon reaching Q8, equivalent to pin 9, it once again connects to pin 13 of IC3, causing IC3 to halt counting regardless of the input signal. When pin 13 is high, it results in the disregard of the clock pulse at pin 14, signifying that the process is repeated.
This also leads to a reset of pin 15 of IC2, initiating counting by IC2 once more, while IC3’s counting is deactivated. Essentially, it signifies that as IC3 counts and generates output signals, they are conveyed in reverse direction to IC2, and vice versa, resulting in alternating counting sequences between the two ICs.
