Navigation-Grade Closed-Loop MEMS Accelerometer Receives Development Contract - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design

Navigation-Grade Closed-Loop MEMS Accelerometer Receives Development Contract

Physical Logic of Petah Tikva, Israel received a customer contract for $2 million for continuing development of a new-generation navigation-grade closed-loop micro-electromechanical (MEMS) accelerometer, the MAXL-CL-4000.

The new accelerometer is designed to meet the market needs of small size, low power consumption, and low-cost navigation-grade inertial measurement unit with long-term bias repeatability below 0.25mg and long-term scale factor repeatability below 250 ppm, with a tunable sensing range between 15g to 70g.

Low sensor power consumption, below 120mW, and a unique mechanical design to achieve a uniform heat dissipation within the package, will enable sub µg/min drifts after less than 1 min from turning on the system. This enables Physical Logic’s high-end MEMS accelerometers to comply with various applications such as: North finding, target location and inertial navigation.

The sensor is designed with the same MEMS die of the company’s MAXL-CL-3000 series. A new ASIC and new electronics approach will enable integration in all electronics features into a stand-alone, hermetically sealed 44LCC ceramic package.

The MAXL-CL-4000 generation will be added to the currently available MAXL-CL-3000 accelerometer family of sensors, which provides a high-performance and low-CSWaP MEMS accelerometer for tactical and navigation applications for input ranges up to 70g and with long-term bias repeatability as low as 500µg and scale factor below 400ppm.

The features of Physical Logic’s closed-loop technology are described in “Achieving More with Less (Cost, Size, Weight and Power) Innovation Accelerates Accelerometers into Higher Levels of Inertial Performance,” an article in the November/December 2021 issue of Inside GNSS. These include excellent scale factor linearity and stability, as well as very low vibration rectification error (VRE) and minimum tradeoff between performance and sensing range.

“Prototypes of MAXL-CL-4000 with long-term bias repeatability below 250 µg and Scale Factor below 250 ppm will be available by mid-2023”, said Aviram Feingold, Physical Logic’s CEO; “but we are not stopping, we are also planning a design of a new closed-loop accelerometer with target long-term bias repeatability below 100µg and SF below 100 ppm. This design is based on the new electronic elements added to MAXL-CL-4000, combined with a new MEMS die. The new die is designed to dump environmental stress effects on the MEMS’ sensing and driving elements by order of magnitude. The sub 100µg sensor program is to answer strategic needs of our customers.”

Photo courtesy Physical Logic.