1. [Publications](/publications) 2. A 9.7fJ/Conv.-Step Capacitive Sensor Readout Circuit with Incremental Zoomed Time Domain Quantization # A 9.7fJ/Conv.-Step Capacitive Sensor Readout Circuit with Incremental Zoomed Time Domain Quantization ![Publication image](/sites/default/files/styles/wide/public/default_images/default.jpeg?itok=qUFsuJCP "Publication image") This paper presents a capacitive sensor readout circuit with an incremental zoom current-controlled oscillator (CCO)-based timedomain (TD) ΔΣM. It supports single-sensor measurement, leading to 2x savings in sensing hardware compared to dual-sensor schemes. A low-cost 5b TD-ΔΣM is implemented with a 7- stage ring-CCO and a double-PFD (DPFD) quantizer. To further boost its speed, a fast start-up scheme is designed for the CCO quantizer. Combining all these merits, the proposed readout circuit achieves 0.23fF resolution while dissipating only 61pJ per conversion with a short measurement time of 4.1μs. To the authors’ best knowledge, it realizes the best energy efficiency and shortest measurement time among all high-resolution capacitanceto-digital converters (CDCs) achieving over 12 ENOB. ## Authors Zilong Shen (Peking University) Xiyuan Tang (Peking University) Zhongyi Wu (Peking University) Haoyang Luo (Peking University) Zongnan Wang (Peking University) [Mingjie Liu](/person/mingjie-liu) Xing Zhang (Peking University) Yuan Wang (Peking University) ## Publication Date Sunday, April 23, 2023 ## Published in [2023 IEEE Custom Integrated Circuits Conference (CICC)](https://ieeexplore.ieee.org/document/10121301) ## Research Area [Circuits and VLSI Design](/research-area/circuits) ## External Links [Paper Link](https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10121301) ## Copyright This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to .