The ST1VAFE3BX is a biosensor embedding a vAFE channel to detect biopotential signals and a high-performance 3-axis digital accelerometer for motion tracking.

The device has been designed with a very compact, low-noise, and low-power vAFE with configurable input impedance. The vAFE enables reading analog signals that are complementary to motion signals. The vAFE and motion signals are intrinsically synchronous, so the result is a unique context-aware edge analysis, thus low power and with the minimum possible latency.

Easy integration and actual synchronization of the vAFE with the accelerometer sensor signal allows standalone processing in the MEMS sensor, leveraging its embedded ecosystem, including the FSM and MLC, and offloading the microcontroller.

The device embeds advanced dedicated features and data processing for signal processing like the finite state machine (FSM), adaptive self-configuration (ASC), and machine learning core (MLC) with exportable AI features/filters.

The ST1VAFE3BX MIPI I3C® target interface and embedded 128-level FIFO buffer complete a set of features that make this device a reference in terms of system integration from a standpoint of the bill of materials, processing, or power consumption.

The embedded accelerometer has user-selectable full scales of ±2g/±4g/±8g/±16g and is capable of measuring accelerations with output data rates from 1.6 Hz to 800 Hz.

The ST1VAFE3BX has a dedicated internal engine to process motion and acceleration detection including free-fall, wake-up, single/double/triple-tap recognition, activity/inactivity, and 6D/4D orientation.

The ST1VAFE3BX is available in a small thin plastic, land grid array (LGA) package and it is guaranteed to operate over an extended temperature range from -40°C to +85°C.

• Dual channels for biopotential signal detection and motion tracking
• Supply voltage range from 1.62 V to 3.6 V
  • Independent I/O supply (1.62 V to 3.6 V) for I²C and SPI interfaces
  • Independent I/O supply (extended range: 1.08 V to 3.6 V) for MIPI I3C^® interface
• Ultralow supply current at 48.1 µA (typ.) in high-performance mode
  • Power-down: 2.6 µA
• Biopotential signal detection channel with analog hub
  • Single-channel, differential input amplifier (vAFE)
  • Programmable gain and input impedance
  • 12-bit ADC resolution
  • ODR up to 3200 Hz when using analog hub / vAFE channel only
• Accelerometer channel
  • Low noise down to 220 µg/√Hz
  • ±2g/±4g/±8g/±16g programmable full-scale
  • ODR from 1.6 Hz to 800 Hz
• Embedded machine learning core
  • For analog hub / vAFE data up to 1.6 kHz
• Programmable finite state machine
  • For analog hub / vAFE data up to 1.6 kHz
• Adaptive self-configuration (ASC) based on the sensor processing output (FSM / MLC)
• Embedded FIFO: up to 128 samples of accelerometer and analog hub / vAFE data or 256 samples of accelerometer data at low resolution
• High-speed I²C/SPI/MIPI I3C^® digital output interface
• Advanced pedometer, step detector and step counter
• Self-test
• Small package: 2.0 x 2.0 x 0.74 (max) mm, LGA 12-lead
• 10000 g high shock survivability
• ECOPACK and RoHS compliant