The LM393 compares this voltage drop to the potentiometer setting. If the reflection is strong enough, the comparator flips the OUT pin to 0V. Interfacing FC-51 with Arduino
The effective detection range of the FC-51 depends on the reflectivity and color of the target object. Black objects absorb IR light (reducing range), while white objects reflect it efficiently (increasing range). Step-by-Step Tuning Power up the module with a 5V source.
The FC-51 IR sensor datasheet provides detailed information on the sensor's specifications, characteristics, and operating conditions. Here's a breakdown of the key parameters: Fc 51 Ir Sensor Datasheet
The FC-51 usually features a 3-pin header for easy connection: Power input (3.3V – 5V). GND: Ground connection. OUT: Digital output signal. Typical Applications Obstacle avoidance for smart cars or robots.
Look at the silkscreen on the PCB. Most modules are labeled "FC-51" and have pins marked as + , OUT , - or similar. Use a continuity tester to confirm ground connections. The LM393 compares this voltage drop to the
The module is designed for simple "object vs. no object" detection rather than precise distance measurement. Specification Operating Voltage 3.0V – 6.0V DC Current Consumption ~23 mA at 3.3V; ~43 mA at 5.0V Detection Range 2cm – 30cm (adjustable via potentiometer) Detection Angle LM393 Voltage Comparator Output Type Digital (HIGH/LOW) Board Dimensions ~3.1cm x 1.4cm (PCB) Pinout and Indicators
Bring the object closer, use a lighter target surface, or turn the potentiometer clockwise. Fluctuating power supply voltage or high electrical noise. Black objects absorb IR light (reducing range), while
Allows users to manually adjust the sensitivity and detection distance. LED Indicators:
All crucial technical parameters are compiled in the table below. This data, compiled from various sources, serves as a reliable reference for engineers and hobbyists integrating the FC-51 into projects.