Sharp Distance Sensor (GP2Y0A21YK0F)

Sharp GP2Y0A21YK0F Distance Sensor overview

The Sharp GP2Y0A21YK0F Distance Sensor is a high-performance infrared proximity sensor that delivers stable, repeatable distance measurements from 10 cm to 80 cm. Using triangulation with a position-sensitive detector (PSD), this sensor provides an analog voltage output that corresponds to the distance to an object, making it ideal for robotics, automation, interactive displays, and educational projects.

How the GP2Y0A21YK0F works

This infrared distance sensor emits IR light and measures the reflected beam’s angle on a PSD to determine distance. Because it relies on triangulation rather than simple intensity, it offers more consistent measurements across varying ambient light and object colors than basic IR reflectance sensors.

Key features

• Detection range: 10 cm to 80 cm
• Analog voltage output proportional to measured distance (suitable for microcontroller ADC inputs)
• Operating voltage: 4.5 V to 5.5 V DC
• Low power consumption, suitable for battery-powered systems
• Compact and lightweight for easy mounting and integration
• Reliable performance less affected by ambient light and surface color

Technical specifications

• Model: GP2Y0A21YK0F
• Detection range: 10 cm to 80 cm
• Output: Analog voltage (Vo) proportional to distance
• Supply voltage: 4.5 V to 5.5 V DC
• Current consumption: low (varies by measurement frequency)
• Interface: 3-pin (Vcc, GND, Vo)
• Dimensions: compact, lightweight package for embedded use

Wiring and interfacing

• Vcc: 4.5 V to 5.5 V DC (do not exceed supply range)
• GND: Common ground with your microcontroller or system
• Vo: Analog output; connect to an ADC pin on your microcontroller (Arduino, ESP32, Raspberry Pi ADC module, etc.)

For best results, add basic smoothing (moving average or low-pass filter) on the ADC readings and sample at a moderate interval to avoid noise. If you need to measure objects at the extreme ends of the range, calibrate with known distances to convert voltage to distance more accurately in your application.

Applications

• Obstacle detection and avoidance for mobile robots
• Distance measurement and object detection in automation systems
• Interactive exhibits, kiosks, and displays
• Security and surveillance proximity sensing
• Educational labs, research, and DIY electronics projects

Tips for best performance

• Keep sensor lens clean and free of dust or smudges.
• Avoid pointing the sensor at very shiny or highly absorbent surfaces without calibration; triangulation helps but extreme surfaces can affect readings.
• Use decoupling capacitors on the supply lines to reduce electrical noise.
• Implement software filtering to smooth out transient spikes in analog readings.
• Test and calibrate in the environment where the sensor will operate for optimal accuracy.

Why choose the Sharp GP2Y0A21YK0F for robotics and automation

The GP2Y0A21YK0F combines a practical detection range (10 cm to 80 cm), a simple analog interface, and robust triangulation-based sensing to provide reliable distance data for embedded systems. Its low power and compact footprint make it particularly suitable for mobile robots, battery-operated devices, and space-constrained installations.

Note: Images are for illustration purposes only.