A robust parasitic-insensitive successive approximation capacitance-to-digital converter

Abstract
In this paper, we present a capacitive sensor digital interface circuit using true capacitance-domain successive approximation that is independent of supply voltage. Robust operation is achieved by using a charge amplifier stage and multiple comparison technique. The interface circuit is insensitive to parasitic capacitances, offset voltages, and charge injection, and is not prone to noise coupling. The proposed design achieves very low temperature sensitivity of 25ppm/oC. A coarse-fine programmable capacitance array allows digitizing a wide capacitance range of 16pF with 12.5-bit quantization limited resolution in a compact area of 0.07mm2. The fabricated prototype is experimentally verified using on-chip sensor and off-chip MEMS capacitive pressure sensor. © 2014 IEEE.

Citation
Omran, H., Arsalan, M., & Salama, K. N. (2014). A robust parasitic-insensitive successive approximation capacitance-to-digital converter. Proceedings of the IEEE 2014 Custom Integrated Circuits Conference. doi:10.1109/cicc.2014.6946080

Publisher
Institute of Electrical and Electronics Engineers (IEEE)

Journal
Proceedings of the IEEE 2014 Custom Integrated Circuits Conference

Conference/Event Name
36th Annual Custom Integrated Circuits Conference - The Showcase for Integrated Circuit Design in the Heart of Silicon Valley, CICC 2014

DOI
10.1109/CICC.2014.6946080

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