A pseudo-differential charge balanced ratiometric readout system for capacitive inertial sensors

This paper presents an open loop readout circuit technique for capacitive inertial sensors using a charge balanced and ratiometric approach. The charge balance is achieved through a delta-sigma loop allowing for direct analog-to-digital conversion at comparatively lower power. Techniques for achieving differential implementation, noise and offset cancellation are also discussed in lieu of the limitations of the physical front end.

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