ProtoCentral MAX30003 — Single‑lead ECG Breakout

Arduino library and examples for the MAX30003 single‑lead ECG analog front end.

Highlights

• MAX30003 AFE: single‑lead ECG, ultra‑low power operation, integrated R‑R (RTOR) detection and QRS timing.
• Board: ProtoCentral breakout with level selection for 3.3V/5V systems, SPI interface, and INT pin for event/RTOR notifications.

Quick features

• Single‑lead ECG measurement (24‑bit ADC samples)
• On‑chip R‑R (RTOR) detection and heart‑rate calculation
• Low power: suitable for battery powered wearables
• SPI interface; interrupt output for beat/flags

Wiring (Arduino defaults used in examples)

MAX30003 signal	Arduino pin	Notes
MISO	D12	SPI MISO
MOSI	D11	SPI MOSI
SCLK	D13	SPI SCK
CS	D4	Chip select (examples default)
INT1	D2	Interrupt / RTOR flag
VCC / 3V3	3.3V / 5V	Power (match board jumper)
GND	GND	Ground

Quick start (example)

#include <SPI.h>
#include "protocentral_max30003.h"

// Use chip select pin D4 (examples default)
MAX30003 max30003(4);

void setup() {
  Serial.begin(115200);
  SPI.begin();

  if (!max30003.readDeviceID()) {
    while (1) { delay(1000); }
  }

  max30003.begin();         // start sensor, default sampling
  max30003.setSamplingRate(MAX30003::SRATE_1000HZ); // optional: change sample rate
}

void loop() {
  int32_t ecg = 0;
  if (max30003.readEcgSample(ecg)) {   // returns true when a new sample is available
    Serial.println(ecg);               // 24‑bit sign‑extended ADC value
  }

  // RTOR / heart rate (library keeps latest values)
  max30003.updateHeartRate();
  Serial.print("HR:"); Serial.print(max30003.heartRate());
  Serial.print(" RR(ms):"); Serial.println(max30003.rrInterval());

  delay(8);
}

Examples

• examples/01-ecg-openview — OpenView / UART packet streaming example
• examples/02-ecg-plotter — Arduino Serial Plotter output
• examples/03-hr-rtor — Heart‑rate and RTOR demonstration

Build & upload using arduino-cli

arduino-cli compile --fqbn arduino:renesas_uno:minima --libraries /path/to/Arduino/libraries /path/to/protocentral_max30003/examples/02-ecg-plotter
arduino-cli upload -p /dev/ttyACM0 -b arduino:renesas_uno:minima -i /tmp/build/02-ecg-plotter.ino.bin

Documentation & support

• Board and getting started: https://docs.protocentral.com/getting-started-with-max30003/
• Product page: https://www.protocentral.com/open-medical-devices/1149-protocentral-max30003-single-lead-ecg-breakout-board.html

Licenses

• Hardware: CERN-OHL-P v2 (see LICENSE.md)
• Software: MIT (see LICENSE.md)