Traffic Light ControlPREPARED BY:Sherasiya Akaram (ID NO: 09EC04) Shukla Dhaval (ID NO: 09EC67)

Department of Electronics & CommunicationShankersinh Vaghela Bapu Institute Of Technology,Vasan.

INTRODUCTION• One way traffic light controllers having three signal Red, Green and Yellow • To ensure that suitable traffic signals are provided to reduce accidents and improve conditions for public transport

Signal To Stop Signal to Proceed With Caution

Signal To Go-Ahead

How Traffic Light Control Work ?• The circuit based around 555 Timer IC (Astable mode) + 4017B Johnson counter • The 555 astable circuit provides clock pulses for the 4017 counter which has ten outputs (Q0 to Q9)• the sequence of the traffic lights is spread over 10 clock pulses

PART LIST IC1. NE555 2. 4017BSEMICONDUCTOR LIST1. D1 TO D6: 1N41482. L1,L2,L3 : LED 

RESISTOR LIST1. 3*01 K OHM2. 1*10 K OHM3. 2*22 K OHM4. 1*100 K OHMCAPACITOR1. 47 µF2. 0.01 µF3. 6.8 nF

MISCELLANEOUS1. 16 pin IC socket2. 08 pin IC socket3. Battery snap4. 2 pin battery connecter

CIRCUIT DIAGRAM

WORKING OF CIRCUIT• The 555 timer IC is connected for Astable Operation, the clock pulses are fed to the 4017 IC via the 10K resistor. • The 4017 is a 10 stage counter, therefore the sequence of the traffic lights is spread over 10 clock pulses, 4on red, 1 on red & amber, 4 on green and 1 on amber

• Each output becomes high in turn as the clock pulses are received. Appropriate outputs are combined with diodes to supply the amber and green LEDs. The red LED is connected to the ÷10 output which is high for the first 5 counts (Q0-Q4 high), this saves using 5 diodes for red and simplifies the circuit.

OBSERVATION TABLE4017 COUNTER HIGH RED YELLOW GREEN

Q0 and ÷10 OnQ1 and ÷10 OnQ2 and ÷10 OnQ3 and ÷10 OnQ4 and ÷10 On On OnQ5 OnQ6 OnQ7 OnQ8 OnQ9 On

APPLICATION• Control the flow of traffic• Reduce the risk of accidents

REFERENCE• www.clarkson-uk.com• www.rshelectronics.co.uk