Swiss electronics firm ST Microelectronics will demonstrate at next week’s Embedded World in Nuremberg a MEMS accelerometer that combines low power, signal processing and low profile for wearable and implantable medical applications.

Produced using biocompatible materials and manufacturing processes, the MIS2DU12 has a 20nA power-down and sub-1µA active mode to extend the operating envelope of implantables such as cardiac monitors and pacemakers. At 0.74mm high, and with a 2 by 2mm footprint, it enables skin patches to become slim, lightweight and comfortable to wear.

In skin patches such as glucose monitors and other bio-parameter sensors, the device’s sensor fusion ensures precision even during macroscopic motion and environmental stress. The applications benefit from high micro-motion sensitivity and power efficiency. The dedicated internal engine for motion processing detects free-fall, wake-up, single and double-tap, activity and inactivity, and calculates 6D and 4D orientation. There are also built-in self-test and an embedded temperature sensor.

With integrated motion processing for event detection and wake-up, it contains an anti-alias filter to increase output-data quality. By removing out-of-band vibration sources, this filter offloads the main application processor to help cut system power consumption. The sensor draws 0.47μA in low-power active mode with 1.6Hz output data rate, and 5.6µA in normal operation with the anti-alias filter enabled.

It has user-selectable full scales of ±2g, ±4g, ±8g and ±16g, output data rates from 1.6 to 800Hz, and operates from -40 to +85˚C. An integrated 128-level FIFO buffer provides data storage and flexibility to save system power consumption.

For rapid evaluation, the Steval-MKI255A (www.st.com/en/evaluation-tools/steval-mki255a.html) adapter board contains a MIS2DU12 sensor and has a standard DIL24 pin arrangement for use with the Steval-MKI109D evaluation board. The board includes a 32bit microcontroller and is ready to use with STM’s MEMS Studio GUI.

The MIS2DU12 (www.st.com/en/mems-and-sensors/mis2du12.html) is in production in the 2.0 by 2.0 by 0.74mm plastic land grid array (LGA) package and available by the middle of this year.

The medical motion sensor will be demonstrated on stand 148 in Hall 4A at Embedded World (www.embedded-world.de) from March 10-12 in Nuremberg, Germany.