Title
A 72-Channel Resistive-and-Capacitive Sensor-Interface Chip With Noise-Orthogonalizing and Pad-Sharing Techniques
Author
Feng, Xiangdong (Zhejiang University; Nanhu Brain-Computer Interface Institute)
Luo, Yuxuan (Zhejiang University)
Cai, Tianyi (Zhejiang University)
Xuan, Yangfan (Zhejiang University)
Zhang, Yunshan (Microaiot)
Shen, Yili (Zhejiang University)
Yang, Changgui (Zhejiang University)
Xiao, Qijing (Zhejiang University)
Du, S. (TU Delft Electronic Instrumentation) 
Zhao, Bo (Zhejiang University; Nanhu Brain-Computer Interface Institute)
Date
2024
Abstract
The growing trend of the Internet of Things (IoT) involves trillions of sensors in various applications. An extensive array of parameters need to be gathered concurrently with high-precision, low-cost, and low-power sensor nodes, such as resistive (R) and capacitive (C) sensors. Single-chip channel fusion can be an effective solution, while it is challenging to suppress the noise and integrate massive I/O pads. However, conventional oversampling noise-shaping methods increase power consumption, which fails to meet the demand of long-term monitoring applications. In addition, existing R/C sensor-interface chips require a pair of I/O pads for each sensor, where the pad frame dominates the overall chip area in massive-channel integration. In this work, we demonstrate a 72-channel R&C sensor-interface chip for proximity-and-temperature sensing. A noise-orthogonalizing technique is proposed to eliminate the quantization noise at the signal frequencies, achieving an energy efficiency of 19.1 pJ/step/channel. Moreover, a pad-sharing technique is proposed to reduce the number of I/O pads by half, enabling 72 sensors to be read by 36 pairs of I/O pads. The chip is fabricated by 65-nm CMOS technology, and measurement results show resolutions of 286 Omega and 162 fF, respectively. The power consumption and die area are reduced to 0.74 mu text{W} /Channel and 0.038 mm2/Channel, respectively.
Subject
Low power
multichannel sensing
noise-orthogonalizing
pad-sharing
sensor interface
To reference this document use:
http://resolver.tudelft.nl/uuid:d3cdc49f-3d2c-4b85-b8f4-0f63af6193d8
DOI
https://doi.org/10.1109/JSSC.2023.3344587
Embargo date
2024-07-23
ISSN
1558-173X
Source
IEEE Journal of Solid State Circuits, 59 (3), 702-715
Part of collection
Institutional Repository
Document type
journal article
Rights
© 2024 Xiangdong Feng, Yuxuan Luo, Tianyi Cai, Yangfan Xuan, Yunshan Zhang, Yili Shen, Changgui Yang, Qijing Xiao, S. Du, Bo Zhao