An IR Transmitter and receiver control any device remotely. Infrared communication is a very common, easy-to-use, and inexpensive wireless communication technology. This generally comprises a transmitter and a receiver pair.
This tutorial explains the simple functioning of an IR transmitter and a receiver using a 555 Timer IC. Here the TSOP1738, which is a transmitter, receives an infrared signal. And a simple IR LED transmits the signal. The receiver TSOP1738 consists of the photodetector, a gain control, a bandpass filter, a demodulator, and a pre-amplifier. An IR LED ejects an infrared light in the range of an infrared frequency. These Infrared lights are invisible to human eyes.
Hardware Components
The following components are required to make IR Transmitter and Receiver Circuit
| S.No | Component | Value | Qty |
|---|---|---|---|
| 1. | LED | – | 1 |
| 2. | Battery | 9v | 1 |
| 3. | IR LED | – | 1 |
| 4. | IC | NE555 Timer | 1 |
| 5. | IR Sensor | TSO1738 | 1 |
| 6. | PNP Transistor | BC557 | 1 |
| 7. | Resistors | 20k, 10k, 1k, 470 ohms | 1, 1, 1, 2 |
| 8. | Ceramic Capacitor | 0.01uF, 1nF | 1, 1 |
| 9. | Electrolytic Capacitor | 1uF, 100uf | 1, 1 |
| 10 | Push Buttons | – | 1 |
555 IC Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 555 Timer
TSO1738 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of TSO1738
Infrared Transmitter Circuit
Infrared Receiver Circuit
Working Explanation
An IR transmitter and receiver pair form a simple circuit. This project explains the principle of IR communication. The 555 Timer IC operates in an astable mode. It generates continuous pulses of the frequency. As the switch is pressed, the connection between an IR LED and the 555 timer IC closes.
Then the IR LED emits light of some frequency. As this modulated infrared light passes through the line of an IR receiver, it detects the signal. After that, the receiver then demodulates the signal. Normally the output of the IR receiver is high as it detects the signal its output becomes low. The transmitter is connected to the PNP transistor which then turns on the transistor which turns the LED on.
Application
The most common use of Infrared communication is the remote control of different appliances like television, air-conditioning, etc.
- It can be used for simple remote controlling applications or small data transfers.
- Several other applications like security applications, proximity sensors, and distance measurement applications. etc. uses this project.
