Four Way Traffic Lights Circuit using 555 Timer IC

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We will build a circuit in this traffic light project to control a four-way signal. The 555 Timer IC and a decade counter are equipped for the circuit. The timer produces pulses, which are supplied to the 10-stage decade counter.

TEN is a memory of the 10-stage DECADE COUNTER. Up to ten pulses can be counted. The counter admits it as an event and commemorates it after every clock peak. The number of memorized activities is shown with the corresponding pin.

Hardware Component

The following components are required to make Traffic Lights Circuit

S.no	Component	Value	Qty
1.	Supply voltage	+9v to +12v	1
2.	IC	NE555 timer	1, 1
3.	Resistor	1K, 10K, 220 Ohm	1, 1, 1
4.	IC	CD4017
5.	LED	–	12
6.	Diode	IN4007	8

CD4017 Pinout

For a detailed description of pinout, dimension features, and specifications download the datasheet of CD4017

555 IC Pinout

For a detailed description of pinout, dimension features, and specifications download the datasheet of 555 Timer

Traffic Lights Circuit

Working Explanation

The following schematic shows a four-way diagram of traffic lights utilizing the 555 Timer IC. The timer produces approximately 100ms of pulses over time. The ON time then is 50ms and the OFF time is 50ms. Changing the capacitor value will adjust the time. Although street lights last 2 minutes in shift time, the time to test the circuit here is reduced.

The time shift for a 4-way traffic light in this circuit can be accomplished by replacing the 10uF capacitor with one 470uF. After the power is set on, the timer works like a square wave generator and produces a clock, and this clock is fed to the DECADE BINARY COUNTER. For instance, when the decade binary counter counts, the number of pulses supplied by the clock is counted as long, and the pin output is high. There will be a spike every 100ms. This spike will give the counter-memory one, and the output will also be.