Digital TTL level (Low logic when obstacle is detected) Output Drive Capability: Clean signal, greater than 15mA Dimensions: 32mm × 14mm Mounting Hole Size: 3mm (Screw diameter) Pinout Configuration
The FC-51 module houses an onboard or a standard LM393 voltage comparator IC, alongside an IR emitter and receiver pair.
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The sensitivity is too low, or the power supply voltage is dropping below 3.3V. Fc 51 Ir Sensor Datasheet
When an object comes within the sensor’s field of view, the IR light bounces off the object and into the phototransistor. The onboard comparator circuit (usually an LM393 chip) then processes the signal and outputs a clean , which can be read directly by a microcontroller.
| Parameter | Value | | :--- | :--- | | | 3.3V – 5V DC | | Current Consumption | Approx. 20mA – 30mA | | Detection Distance | 2cm to 30cm (Adjustable) | | IO Interface | 4-pin (VCC, GND, OUT, EN*) | | Output Signal | Digital (TTL Low when object detected) | | Sensor Chip | LM393 Comparator | | IR Wavelength | 950 nm | | Effective Angle | Approx. 35° | | Dimensions | Approx. 32mm x 14mm | | Operating Temperature | 0°C to +50°C |
A: If your module has an AOUT pin, read it using an ADC pin. If not, you can solder a wire directly to the phototransistor's collector or the comparator's non-inverting input. Digital TTL level (Low logic when obstacle is
FC-51 Sensor Arduino Uno / Microcontroller +--------------+ +--------------+ | VCC |------------------->| 5V | | GND |------------------->| GND | | OUT |------------------->| Digital Pin 2| +--------------+ +--------------+ Pull-Up Resistor Notice:
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.
The is an affordable, highly efficient electronic module widely used in robotics, automation, and smart home projects. Utilizing infrared (IR) light, this active sensor detects objects within its line of sight, making it a staple for autonomous navigation and proximity sensing. When an object comes within the sensor’s field
Authentic FC-51 modules are manufactured by various Chinese factories, but counterfeit or substandard copies exist.
A: You may have set the sensitivity too high. The sensor is detecting the floor or table surface. Turn the potentiometer counter-clockwise until the detection stops.
While highly functional, the FC-51 has inherent limitations due to the physics of infrared light: