A 10 bit very low-power CMOS SAR-ADC for capacitive micro-mechanical pressure measurement in implants. Adv Radio Sci 4:243-246

Advances in Radio Science 09/2006; 4. DOI: 10.5194/ars-4-243-2006
Source: DOAJ


This paper presents the development of a 10 bit very low-power CMOS SAR-ADC to be used in medical implants. The first part discusses the principle schematic and the requirements for component matching and the comparator of the ADC. Additionally, the measurement results of a fabricated test chip will be given. The second part of this paper discusses the possibility of direct on-chip implementation of a capacitive pressure sensor in a switched-capacitor SAR-ADC.

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    • "The proposed circuit is realized by incorporating a pressure sensor and a ranging capacitor array into successive approximation register (SAR) technique. The pressure sensor sometimes has large parasitic capacitance, and it degrades the dynamic range of the conventional readout circuits using the SAR technique [14] [15]. The proposed circuit can cancel the parasitic capacitance by using the ranging capacitor array, which also enables to shift output-code range into intended range of sensor capacitance . "
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