Heartbeat Sensor Module (SKU#KY039)

This Finger Clip Heart Rate Sensor Module KY039 uses a bright infrared (IR) LED and a phototransistor to detect the pulse of the finger (Heartbeat), a red LED flashes with each pulse.

Connecting to the Arduino

1. Sensor pin - connect to Arduino pin Analoog 0 / A0
2. Sensor pin + (middle pin) connect to Arduino pin 5+
3. Sensor pin S connect to Arduino pin GND

Pulse monitor works as follows:

• The LED is the light side of the finger, and the phototransistor is on the other side of the finger, The phototransistor is used to obtain the flux emitted when the blood pressure pulse by the finger when the resistance of the phototransistor is slightly changed.
• We chose a very high resistance resistor R1, because most of the light through the finger is absorbed, it is a desirable phototransistor sensitive enough. Resistance can be selected by experiment to get the best results.
• The most important is to keep the shield from stray light into the phototransistor. For home lighting that is particularly important because the lights at home are mostly based on 50HZ or 60HZ fluctuate, so a faint heartbeat will add considerable noise.

Download

• Arduino Simple Example Code