Ultra low power accelerometer

This assignment is intended as a continuation of a 2018 Master's thesis in which a MEMS accelerometer was developed for use with Disruptive Technologies' capacitive sensing ASIC, resulting in an experimental device with lower current consumption than any commercially available solution.

The assignment may involve one or more of the following:

• Improve the physical design of the MEMS element
• Reduce the physical footprint from 4 mm x 3 mm to 2 mm x 2 mm or less.
• Modify the design to allow for sensing along both in-plane axes, while minimizing cross-axis sensitivity.
• Modify the design to allow for sensing along the out-of-plane axis. This may require the use of a different fabrication process.
• Optimize critical parameters such as the comb widths, proof mass size and spring geometry.
• Incorporate a self-test structure to allow for automated testing during manufacturing and as part of regular health-checks after the sensor is deployed in the field.

Investigate alternative techniques for fabrication, packaging, and integration with the sensing ASIC. How do these techniques affect manufacturability, sourcing and scalability?

Optimize the analog interface to improve linearity, sensitivity, and robustness against electromagnetic interference. This may involve reconfiguring the existing ASIC and/or designing a modified circuit that can be incorporated in a new revision.

Characterize the dies that have already been fabricated with respect to frequency response, tolerance to electromagnetic fields, and response to shock. Estimate tolerances and temperature coefficients. Describe algorithms for simple applications such as fall detection and tilt measurements based on the analog output of the sensor.

The assignment is well suited for continuation into a Master Project. Disruptive Technologies will at agreement cover costs for development and production of a device.

Feel free to make direct contact with the Disruptive Technologies external supervisor under it this sounds interesting.

Supervisor: Jonathan Reichelt Gjertsen, Disruptive Technologies jonathan.gjertsen@disruptive-technologies.com