Automatic Street Light Controller Circuit Using LDR And 555 Timer IC

We are living in the world where everything goes to be automatic from your washing machine to your ceiling fan. Street lights are one of those examples of the automatic world. Automatic street light are those light which needs no manual operation to gets turn ON and turn OFF. Did you ever try to make such kind of street lights that gets turn ON and turns OFF automatically? In this article, we are going to make automatic street light using LDR and 555 timer IC.

List of Components  
  1. 555 Timer IC
  2. LDR
  3. LED
  4. Potentiometer
  5. Resistor 1* 1k ohm 
  6. Resistor 1* 220 ohm
  7. 9V Battery
  8. Printed Circuit Board(PCB) Or BreadBoard 
Circuit Diagram
A very simple circuit diagram of automatic street light is given below. 
automatic street light controller circuit using ldr
Automatic Street Light Controller Circuit

Principle and Working of Automatic Street Light Controller

555 Timer IC is the main part of the circuit that works as a comparator. All the working of this circuit depends on the working of the 555 timers Ic.To know more about 555 times IC read this article Working of 555 Timer IC. In this circuit pin, 3 produce output which has just two states high and low. Output goes to high when  trigger pin  is at a lower level than the 1/3rd level of the power supply voltage and output goes low when trigger pin 2 is at above then 1/3rd  of the power supply voltage. In this circuit pin, 4,6 and 8 are connected to the power supply. Here we use LDR to detect the presence of light which is formed a potential divider circuit with the help of 1k ohms resistor. LDR is a special type of resistor whose value depends on the light. Read this article to know How LDR Works. The output of this divider circuit is given to trigger pin of the 555 timer IC. 

In this circuit, we use a simple LED to know how the whole circuit works. You can also connect as much led as you want by using the transistor or you can connect a Relay to control high voltage electrical bulbs. 

You must use caution while connecting Relay to this circuit because its may be danger and as different bulb have different wattage.

Video Demonstration of Automatic Street Light Controller


  1. how did you make this circuit diagram? Did you use creately like software ?

    1. Hello shalin,
      You can make this circuit using proteus if you don't know how to use proteus then visit here

  2. how to connect ldr potentiometer nd resistor ????
    plz provide in figure i completed the circuit but not working

    1. I want to properly result of this project

    2. Hi Neha,

      Make sure You have done all the circuiting correctly. Check your connection once again and let me know further



      This project was working fine from my side, make sure you have done your connection correctly.

    4. is not working me may you help me please

  3. this project i was doing as final year project last day it didn't work so i was wonering if you help me

  4. Hey I want budget of this project

  5. This is not Working!!!!!!!!!!!!!!!!!!!!!!!!

  6. Kindly Ap is Circuit ko PCB ya Bread Board per bana kar shown kar sakthy hia............Because m na kia but surf led on ho rehe ha sensor kam nhi kar raha........or agar chip 555 ko circuit sy bhir kar doo tub bhe surf led on hote ha.

  7. Our Project work going in on chennai region kindly update the boom lift rental in ahmedabad member.

  8. In Practiacaly how many volts are give to this project..

  9. Hi Sachin, Good Post.For the best engineering projects in electrical and electronics branch, you will get the idea from the which is purely for electrical and electronics department. This website for last year projects for Electronics Engineers. It has good stuff about Electronics Projects for Final Year Students Where they can find various Projects ideas and tutorials on Microcontroller, Electric Circuits and more. This is the good platform where you can post your projects.
    Visit : Engineers Garage and 555 Timer Circuit