TSOP1838 Metal 38kHz IR Distance Sensor Receiver

Specifications

• Model: TSOP1838 (Metal)
• Operating Voltage: 2.7V to 5.5V DC (Compatible with 3.3V and 5V logic)
• Carrier Frequency: 38 kHz
• Receiving Distance: Up to 18 meters (depending on transmitter power)
• Reception Angle: ± 45 degrees
• Output Signal: Active Low (Idles HIGH, drops LOW when a signal is detected)
• Current Consumption: 0.4 mA to 1.5 mA (Typical)
• Immunity: High immunity against ambient light and electrical noise
• Internal Protection: Built-in PCM frequency filter

Applications

• Smart Home Automation: Decoding signals from standard TV/AC remotes to trigger relays and smart routines.
• Robotics: Building IR beacons, remote-controlled rovers, or proximity detection systems.
• Media Centers: Adding IR remote capabilities to Raspberry Pi Kodi/OSMC setups.
  Interactive Art: Creating installations that respond to hidden remote triggers.

Unlock New Capabilities

• The Prerequisite: If you've mastered blinking LEDs or reading simple pushbuttons, you are ready for wireless control.
• The Upgrade: The TSOP1838 unlocks the ability to use any old TV or DVD remote lying around your house as a multi-button input device for your microcontroller.
• Effort Level: Beginner. You only need this sensor, an Arduino or ESP32, three jumper wires, and the standard IRremote library to start decoding signals in under 10 minutes.
• Virtual Technician: Wiring & Safety Guide
• ⚠️ Warning: Pay close attention to the pinout. Reversing the power (VCC and GND) will permanently damage the internal preamplifier instantly. Always face the plastic bump (the receiver dome) toward you when identifying pins.

Pin Mapping (Facing the dome):

• Left Pin (OUT): Connect to any Digital Input pin on your microcontroller (e.g., Arduino Pin 11).
• Center Pin (GND): Connect to Ground.
• Right Pin (VCC): Connect to 3.3V or 5V.

Package Includes:

• 1x TSOP1838 Metal 38kHz IR Distance Sensor Receiver

Frequently Asked Questions (Technical FAQ)

• What is the maximum range of the TSOP1838?
  Under optimal conditions, it can receive signals up to 18 meters away, though this heavily depends on the strength of the IR transmitter being used.
• Will this work with a 3.3V microcontroller like the ESP32?
  Yes, the operating voltage is 2.7V to 5.5V, making it fully compatible with 3.3V logic without logic level shifters.
• Why am I getting random or garbage hex codes in my serial monitor?
  This is usually caused by ambient light interference (like strong sunlight or cheap fluorescent lights) or an incorrect carrier frequency (e.g., using a 40kHz remote).
• How do I know which pin is which?
  With the rounded dome facing you, the pins from left to right are: OUT, GND, VCC.
• Can the TSOP1838 transmit IR signals?
  No, it is strictly a receiver. You need an IR LED to transmit signals.
• Does it need an external pull-up resistor?
  No, the TSOP1838 has an internal pull-up resistor. The output pin idles HIGH and pulses LOW when it detects a 38kHz signal.
• Can I use this for line-following robots?
  It is not ideal. While possible, simple IR photodiodes are better for line following. The TSOP1838 is designed specifically for decoding modulated 38kHz signals, not continuous reflection.
• Why did my sensor get incredibly hot and stop working?
  You likely wired VCC and GND backward. Reversed polarity destroys the sensor instantly.
• Will this decode my Air Conditioner remote?
  Yes, but AC remotes send much longer, more complex data arrays than TV remotes. You will need a library specifically capable of handling long raw buffers (like IRremoteESP8266).
• What is the difference between the plastic and metal versions?
  The metal version (like the TSOP1738) has a metal shield that provides slightly better protection against electromagnetic interference (EMI), but the plastic version is sufficient for 95% of DIY projects.
• Do I need a decoupling capacitor?
  While not strictly required for basic breadboard testing, adding a 4.7µF capacitor across VCC and GND close to the sensor is highly recommended to filter out power supply noise.
• Can it detect motion like a PIR sensor?
  No. It only detects 38kHz infrared light pulses, not the passive body heat detected by PIR sensors.
• Which Arduino library should I use?
  The standard IRremote library by shirriff is the most popular and easiest to use for basic decoding.
• How fast can it receive data?
  It is designed for standard remote control protocols (NEC, Sony, RC5), which operate at low baud rates (typically under 2400 bps). It cannot be used for high-speed data transfer.