TSOP38238 IR Receiver Diode (38kHz)

The TSOP38238 is a simple IR Receiver Diode generally used along with IR remotes to detect IR signals. This Receiver diode can receive IR signals from Remotes operating on 38kHz and most remotes in India like TV Remotes, AC Remotes, etc operate on 38kHz. The Diode consumes less power and is designed to suppress the noise or disturbance signals from other external sources like incandescent, halogen, fluorescent light, sunlight, etc. The pinout of a TSOP38238 IR receiver is shown below:

As shown in the fig above, when you are facing the flat surface of the IR receiver, the leftmost pin is connected to supply voltage and the center pin is connected to the ground. The rightmost pin is output (active low) and is connected to the microcontroller. When the IR receiver receives the signal from the IR remote (IR blaster), the demodulated output signal from the TSOP38238 module is further decoded using a microprocessor. Certain libraries can be used to decode the signals which follow a certain IR transmission protocol. There are many IR transmission protocols like Sony, Matsushita, NEC, and RC5. Among the most commonly used protocol is the NEC protocol.

Operating Characteristics of TSOP38238

• Operating Voltage: 2.5V to 5.5V
• Operating Frequency: 38Khz
• Current consumption: 3mA
• Output voltage: -0.3 to (Vs +0.3)
• Output current: 5mA

The IR transmitter emits infrared light in the range of Infrared frequency. The transmitter circuit generates IR radiation modulated at 38Khz. It means that the transmitter switches its IR led on and off in a particular sequence at the rate of 38Khz. when coming to the IR receiver, the TSOP’s output is active low, which means that when it detects IR radiation its output is low and when it doesn’t sense IR radiation its output is high. The IR receiver receives the modulated infrared waves (generated from the IR transmitter circuit) and gives the demodulated output signals (electrical signals). These demodulated signals are modulated using a microcontroller like Arduino and stored in the memory.  The Dimension of TSOP38238 is shown below.

Additional Resources

• TSOP38238 Datasheet
• Interfacing TSOP38238 with Arduino
• TSOP38238 Arduino Library