Traffic Light Control
PREPARED BY:
Sherasiya Akaram (ID NO: 09EC04)
Shukla Dhaval (ID NO: 09EC67)
Department of Electronics & Communication
Shankersinh 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
IC
1. NE555
2. 4017B
SEMICONDUCTOR LIST
1. D1 TO D6: 1N4148
2. L1,L2,L3 : LED
RESISTOR LIST
1.
2.
3.
4.
3*01 K
1*10 K
2*22 K
1*100 K
OHM
OHM
OHM
OHM
CAPACITOR
1. 47 µF
2. 0.01 µF
3. 6.8 nF
MISCELLANEOUS
1.
2.
3.
4.
16 pin IC socket
08 pin IC socket
Battery snap
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 TABLE
4017 COUNTER
HIGH
Q0 and ÷10
RED
Q1 and ÷10
On
Q2 and ÷10
On
Q3 and ÷10
On
Q4 and ÷10
On
YELLOW
GREEN
On
On
On
Q5
On
Q6
On
Q7
On
Q8
On
Q9
On
APPLICATION
• Control the flow of traffic
• Reduce the risk of accidents
REFERENCE
• www.clarkson-uk.com
• www.rshelectronics.co.uk