circuir diagram of ir sensorHello everyone, hope you all are fine and having fun with your lives. Today’s tutorial is quite simple and we will have a look at circuit diagram of IR sensor using 555 Timer. There are different types of IR sensors available in the market. IR is abbreviation of infrared and so they use infrared ray for detection of objects. There are many types of IR sensors with different functionality, but in all of them infrared rays are omitted from transmitter and are received by the receiver. and using these ray we can say whether an object is placed in the path or not.

Today we are gonna see how to design your own IR sensor using 555 Timer. We can also interface these IR sensors quite easily with any microcontroller like PIC Microcontroller , Arduino etc. I was also thinking of designing it in Proteus but Proteus doesn’t have the IR leds in it so I couldn’t do it. IR sensors available in market are quite costly ranging from 10$ to 100$ obviously they are also excellent in efficiency but in engineering cost efficiency also plays an important role so today we are gonna have a look at circuit diagram of IR sensor using 555 timer which will cost you just $2. Before going into the details, lets first have a look at types of IR sensors.

Types of IR sensors

  • There are normally two types of IR sensors available in market.

First Type of IR Sensors:

  • First type is transceiver IR sensor which has both transmitter and receiver in it. This type of IR sensor is used to detect the distance of object from the sensor.
  • In this type of IR sensors, rays are omitted from the transmitter and are reflected back after hitting some object and are captured by the receiver.
  • On the basis of the time taken by these rays to reflected back, we calculate the distance of the object from the sensor.

Second Type of IR Sensors:

  • In these types of IR sensors, transmitter and receiver are not on same chip but on seperate pieces.
  • These types of IR sensors are used for detection of object.
  • For example we need to count people entering in some room then we will place this IR sensor on the door of that room with transmitter on one end and receiver on the other.
  • So, now when some one will enter through the door , he will cut the IR beam and thus the IR light wont be received by the receiver and thus the sensor will know that someone entered.
  • These types of IR sensors are also used in electronic devices like TV remote etc.

In this tutorial we are gonna design this second type of IR sensor using 555 timer. so, lets get started.

Circuit Diagram of IR Sensor using 555 Timer

  • So, here we are gonna design the second type of IR sensor using 555 timer.
  • In this sensor we need to design both the transmitter and the receiver.
  • So, lets get started the transmitter.
  • Design the below circuit on some circuit board:

IR sensor design, circuit diagram of ir sensor

  • In the above circuit diagram of IR sensor, I have clearly mentioned all the values of components so that you can easily design it. Moreover there are two leds used in it, these are not simple leds. There are IR leds which emits IR rays. the range of this sensor will depend roughly on the number of leds you are gonna use here, as I used two leds.
  • So, now lets have a look at circuit diagram of receiver side.

IR sensor design, circuit diagram of ir sensor

  • On this side we have use IR led but that one is receiving and will received that IR rays coming from the transmitter IR leds.
  • These are quite simple in designing and you can design it without any trouble. Before going into PCB, its better if you first design them on some wero board or bread board.
  • Here’s a manufactured piece of the above given circuit diagrams. The one with two leds is the transmitter and the other one is receiver.


circuir diagram of ir sensor

  • The image is a bit blur, coz I was in a bit of hurry but they work perfectly fine. 🙂
  • That’s all for today, will see you guys in the next tutorial. Till then take care!!!


  1. I want to do my project relating to Automatic flushing system consists of IR Sensor,PLC,TIMER,Solenoid valve
    How am i going to connect?
    Help me please
    This is my final year project.

    • Hi,

      Add me on Skype and we will discuss it in detail. We can provide you the complete project. My Skype id is theenggprojects.


  2. Re: Circuit Diagram of IR Sensor using 555 Timer
    In the picture, it shows that the transmitter and receiver share two common wires between them. Is this so that they can share a common voltage source? Can each one have an individual power source? Like a battery pack for each one? If so, could it be a 9V battery, with no step down? Thanks…

  3. Hey! I really like your article, it’s easy for beginners to understand the circuit designing. Can we use this circuit for automation of signals of traffic lights, how can we control the timer? Same circuit will be followed or some modifications there will be, if yes then what will the modifications kindly clear it. More power to you.

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