ProtoCentral ST1VAFE3BX Biopotential AFE + 3-axis Accelerometer Breakout Kit

The ST1VAFE3BX is the latest vital-signs Analog Front End (vAFE) from STMicroelectronics, combining a single-channel biopotential measurement chain with a 3-axis MEMS accelerometer in a single tiny LGA package. The result: capture clean ECG signals while simultaneously tracking motion, all from one chip — ideal for wearables and hearables.

This ProtoCentral breakout is configured for single-lead ECG and ships with a 3-electrode ECG cable. The board exposes a 3.5 mm stereo jack for the included cable, a QWIIC connector for plug-and-play I²C, and a 7-pin header for direct I²C / I³C / SPI access from any microcontroller. A jumper (JP2) selects between the interface modes.

The on-board 1.8 V regulator and dual-rail level shifting let the breakout run from any 2 V–5 V host (Arduino, Raspberry Pi, ESP32, etc.) while keeping the silicon happily within its operating range.

Features

• STMicroelectronics ST1VAFE3BX vital-signs AFE
• Single-lead ECG measurement via included 3-electrode cable and 3.5 mm jack
• 3-axis MEMS accelerometer (selectable ±2 / ±4 / ±8 / ±16 g)
• Triple-mode digital interface: I²C, I³C and SPI — mode-selectable via JP2 jumper or CS pin
• QWIIC connector for solderless I²C daisy-chaining
• On-board 1.8 V LDO and bidirectional logic-level translation
• Wide host supply range: 2 V – 5 V on VCC and I/O
• Compact biopotential signal-conditioning front-end with exposed BIO1 / BIO2 / VCM / IN1 / IN2 test points
• Open-source hardware design (CERN-OHL-P v2)

Typical applications

• Wearable single-lead ECG monitors
• Heart-rate variability (HRV) experiments
• Activity-aware ECG research where motion artefacts must be regressed out
• Hearable / earphone-borne ECG prototypes

Important notice

This device is not a medical diagnostic instrument. It is intended for evaluation, education, and research only.

Safety

When connecting electrodes to the body, ensure the host computer is running on battery power, not mains. This avoids any direct electrical path between mains earth and the user.