The KY‑039 Finger Detection Heartbeat Sensor is a compact optical sensor module designed to measure heart rate and pulse signals using infrared light. By detecting changes in blood flow through a fingertip, it outputs an analog signal that can be read by an ADC (Analog‑to‑Digital Converter) and processed by microcontrollers such as Arduino, ESP32, STM32, and Raspberry Pi.

This sensor is widely used in DIY health monitoring projects, biomedical experiments, and educational electronics, offering a simple and cost‑effective way to explore biosignal measurement.

Specifications

• Module Type: KY‑039 Heartbeat Sensor

• Detection Method: Infrared light reflection through fingertip

• Output Signal: Analog voltage (requires ADC for digital processing)

• Operating Voltage: 3.3V – 5V DC

• Interface: Analog output pin + VCC + GND

• Applications: Heartbeat monitoring, biomedical experiments, Arduino projects, IoT health devices

• Size: Compact PCB for easy integration

Features

• Finger detection via infrared LED + phototransistor

• Analog output for easy interfacing with ADC modules

• Compatible with Arduino, ESP32, STM32, Raspberry Pi

• Low‑cost solution for DIY biomedical projects

• Compact and lightweight design for wearable or portable devices

• Educational tool for learning biosignal measurement and processing