DFRobot Gravity Analog Heart Rate ECG Sensor - AD8232 Chip, 3.3-6V Input

The AD8232 is a dedicated integrated signal conditioner for ECG and other biopotential measurements. It amplifies the microvolt-level signals from the electrodes, applies high-pass filtering to remove motion artifact and DC offset, and includes a low-pass filter for noise reduction. This results in a clean, readable analog voltage output representing the heart's QRS complex.

Connect the module's Gravity 3-pin cable to your Arduino: VCC to 5V, GND to GND, and the Signal (S) pin to an analog input pin (e.g., A0). Attach three ECG electrodes to the patient and connect their leads to the module's snap terminals. In your Arduino sketch, use analogRead() on the chosen pin to sample the voltage waveform, then implement an algorithm to detect peaks and calculate beats per minute (BPM).

Yes, the module is fully compatible with 3.3V logic microcontrollers. You can power it with 3.3V from the ESP32 or Pi's GPIO header. The analog output range remains 0-3.3V, which matches the ADC reference voltage of these 3.3V systems, ensuring full-scale readings without risk of damage. Ensure your power supply can deliver the required <10mA current.

Use standard disposable or reusable pre-gelled ECG electrodes with snap connectors. The module has three snap terminals typically labeled for Right Arm (RA), Left Arm (LA), and Right Leg (RL) leads, following a simplified three-lead configuration. Ensure good skin contact and proper lead placement (e.g., RA on right wrist, LA on left wrist, RL on right ankle) for a clear signal.