STMicroelectronics has introduced the MIS2DH, an ultra-low-power 3-axis accelerometer specifically designed for medical applications, including implantable devices classified by U.S. Food and Drug Administration (FDA) as Class III. The accelerometer is an off-the-shelf device that can enable functions such as activity monitoring and posture sensing to be included in a wide range of medical applications. 

Implantable medical devices such as cardiac pacemakers, ICDs (Implantable Cardioverter Defibrillator), and neurostimulators have been successfully used for many years to prolong the lives of patients with heart problems or to make life better for people with chronic pain conditions.  Today, there is a growing interest in the medical world in exploring how new implantable devices could help treat other chronic problems such as high blood pressure, epilepsy, and tremor-related conditions. For most of these applications, an embedded accelerometer capable of measuring the activity and posture of the patient is important to manage the stimulus delivered by the implantable device and therefore to improve the effectiveness of the treatment and the wellbeing of the patient. 

Until now, a major obstacle for SMEs (Small and Medium Enterprises) wanting to develop innovative new medical devices has been the high costs associated with custom-designed sensors and obtaining FDA certification. The MIS2DH addresses this problem by combining a 3-axis mechanical element and an integrated electronic circuit in a single package, along with a set of collaterals required by customers seeking FDA Class III approval:

• Dedicated Manufacturing and Testing flow, including additional checks, screening and process control
• Guaranteed retention of production records for more than 10 years;
• Product-change management and notification aligned with medical standards;
• Each batch is shipped with a Certificate of Conformity (CoC);
• Long-term longevity commitment.

Key technical features of the MIS2DH include:

• 3-axis accelerometer;
• ultra-small size (2x2x1mm³);
• ultra-low power consumption (down to 2μA in low-power mode);
• ±2g/±4g/±8g/±16g selectable full-scale;
• 8-, 10- and 12-bit operating modes;
• 1Hz – 5KHz output data rate;
• FIFO buffer and programmable interrupt to minimize system power consumption;
• I2C/SPI digital outputs;
• 1.71 -3.6V operating voltage. 

The device is available now in volume. 

STMicroelectronics
www.st.com