Japanese multinational conglomerate company Hitachi, Ltd. announced that it has developed a new MEMS accelerometer that can detect vibrations up to three orders of magnitude smaller than previous designs that target automotive applications.
The new accelerometer mixes previous MEMS technology with circuit-based technology, resulting in an achieved sensitivity that compares to that of sensors used for oil and gas exploration but at a fraction of the power consumption. The high-sensitivity low-power MEMS accelerometer can detect vibrations as low as 30 ng/√Hz and only consume 20 mW, less than half the power usage of previous sensors.
The challenge that Hitachi faced was creating a sensor that was powerful enough to detect low-frequency vibrations without using a massive amount of power. Doing that is difficult because the power required for sensors increases exponentially as the noise floor is reduced.
Control IC, detection IC, and MEMS device in the accelerometer (left), moving mass inside the MEMS device (right). Image source: Hitachi.