
MEMS sensors for wearables build in step counting and gesture recognition
Easy to integrate for fast time-to-market, these MEMS devices offer low power consumption. As well as step counting in wearables such as fitness bands, the sensors can also be used for advanced gesture recognition, such as tilting of the wrist, and can detect activities such as running, walking or conversely, standing still.
The BMA456 provides the highest performance and accuracy of the family, with 16-bit resolution, noise of 120 μg/√Hz, and a total offset over its lifetime of only 20 mg. Temperature Coefficient of Offset (TCO) is ±0.3 mg/K, ensuring activity tracking remains accurate under all conditions.
These acceleration sensors are housed in packages measuring 2.0 x 2.0 mm. The BMA456 has a very low height of only 0.65 mm, which makes this sensor easy to design into space-constrained wearable applications such as fitness trackers, smartwatches, and hearables. Power consumption of the step counter is low, typically less than 30 μA, which helps maximize battery life in portable devices. The sensors can be used to put wearables into sleep mode even during step-counting, thereby helping to reduce overall power consumption.
BMA456 and BMA423 will be available via distributors in August 2017.
Bosch Sensortec; www.bosch-sensortec.com
