Overview

The Pulse and Heart Rate Sensor Module is a compact device that measures heart rate by detecting changes in blood flow through a fingertip. It typically uses:

• Infrared LED & photodiode (or phototransistor) to sense pulse signals.
• Analog output that can be read by a microcontroller.
• Sometimes includes signal conditioning circuitry to reduce noise.

Pinout & Connections

Setup Instructions

1. Connect the module:
   • VCC → Arduino 5V (or 3.3V depending on board).
   • GND → Arduino GND.
   • OUT → Arduino analog input (e.g., A0).
2. Placement:
   • Place your fingertip gently over the sensor.
   • Avoid pressing too hard (can distort readings).
   • Keep still to minimize motion artifacts.
3. Power considerations:
   • Use stable 5V supply.
   • Avoid noisy power sources.

Arduino Example Code

int sensorPin = A0;

void setup() {
  Serial.begin(9600);
}

void loop() {
  int sensorValue = analogRead(sensorPin);
  Serial.println(sensorValue);
  delay(10);
}

• The raw values will fluctuate with each heartbeat.
• You can process these values to detect peaks (heartbeats).

Heart Rate Calculation

1. Record sensor values over time.
2. Detect peaks (signal rises above threshold).
3. Count beats in a fixed interval (e.g., 15 seconds).
4. Multiply by 4 → Beats per minute (BPM).

Example:

• 20 beats in 15 seconds → 20 × 4 = 80 BPM.

Applications

• Fitness monitoring projects.
• DIY health trackers.
• Educational demonstrations of biomedical sensing.
• IoT health monitoring systems.

Notes & Best Practices

• Accuracy: This is a hobby-grade sensor, not medical-grade.
• Environment: Use in stable lighting; avoid direct sunlight.
• Motion artifacts: Keep finger steady for reliable readings.
• Calibration: Adjust threshold values in code for better detection.

Would you like me to also prepare a step‑by‑step demo project (e.g., Arduino + OLED display showing live BPM), so you can use this module in a classroom or kit demonstration?