void setup() pinMode(sensorPin, INPUT); // Set the sensor pin as an input pinMode(ledPin, OUTPUT); // Set the LED pin as an output Serial.begin(9600); // Start serial communication for debugging
Thanks to its simplicity and reliability, the FC-51 is used in hundreds of projects. Here are the top applications:
| FC-51 Pin | Arduino Pin | | :--- | :--- | | VCC | 5V | | GND | GND | | OUT | Digital Pin 2 (or any digital input pin) |
Used in multi-sensor arrays for basic edge or line detection. Fc 51 Ir Sensor Datasheet
The FC-51 is an , designed primarily for obstacle detection and proximity sensing . It is highly popular in the maker and robotics community due to its low cost, ease of use, and simple digital interface. The module is frequently used in DIY electronics, microcontroller projects, and educational settings.
The onboard photodiode (receiver) captures the reflected light. The intensity of the received light depends on the distance and surface color of the obstacle.
Detects reflected infrared light. It is tinted black to filter out ambient visible light interference. void setup() pinMode(sensorPin, INPUT); // Set the sensor
Placed at the front of wheeled robots to prevent collisions.
The FC-51 IR sensor module is an electronic component used for non-contact object detection and proximity sensing. It serves as a reliable, low-cost digital sensor. This article consolidates its technical specifications, working principle, pin configuration, practical application circuits, and calibration procedures into a single reference. While an official manufacturer datasheet remains elusive, the information here is compiled from technical documentation, component datasheets, and practical experiments, making it an essential guide for engineers, students, and hobbyists alike.
| Symptom | Possible Cause | Solution | | :--- | :--- | :--- | | Output LED always ON | Potentiometer too sensitive; object too close; power supply noise | Turn potentiometer CCW; move objects; add capacitor | | Output LED always OFF | No power; broken IR LED; range too low | Check Vcc/GND; turn potentiometer CW; test with white paper | | Erratic detection | Ambient IR noise (sunlight, CFLs); loose wires | Shield sensor; use shorter wires; add 10ms debounce in code | | Very short range (under 5 cm) | Potentiometer misadjusted; black target | Recalibrate; use reflective tape on target | | Module gets hot | Reverse polarity | Immediately disconnect; check pinout version | It is highly popular in the maker and
The following code configures Pin 2 as an input, monitors the sensor status, and prints the result to the Serial Monitor.
The table below compiles the core specifications for the FC-51 module: