Source-linked AI summary
A 140.5$\mu$W, 99.8% Accuracy, 96.1dB SNR BioZ IC for Real-Time Cell Analysis with On-Demand Push-Pull Excitation and Continuous-Time $\Delta\Sigma$ T-D Readout
Jiayang Li, Junzhe Chen, Xin Zhang, Peiqing Li, Liwen Zhang, Navya Nayak, Yating Zou, Xuanyu Liang, Hubin Zhao, Roshan Weerasekera, Xiao Liu, Reza Haqshenas, Dai Jiang, Martin Cryan, Sohmyung Ha, Andreas Demosthenous, Edoardo Charbon, Dinesh Pamunuwa
TL;DR
BioZ readout must combine high SNR and accurate magnitude/phase measurements with low power. This IC pairs an on-demand push–pull driver with a continuous-time ΔΣ T-D readout, achieving 96.1 dB peak SNR, 99.8% impedance-magnitude accuracy, 0.13° phase error, and 140.5 μW maximum power.
Problem
BioZ analysis needs high SNR and accurate magnitude/phase readout, while parallel testing across many antibiotic conditions also calls for low power per channel.
Source: p. 1Method
The IC combines an on-demand push–pull excitation driver with a duty-cycled current comparator and continuous-time ΔΣ T-D converters that use residual-time feedback.
Source: pp. 1–2Results
96.1 dB peak SNR, 99.8% impedance-magnitude accuracy, 0.13° phase error, and 140.5 μW maximum power were achieved.
Source: p. 1Takeaways & Limitations
The IC was tested on ARPE-19 epithelial cells at 60%, 70%, and 95% nominal confluence across 15.6–250 kHz.
Source: p. 3
Abstract
from arXiv · showhide
This paper presents a bioimpedance IC combining an on-demand push-pull driver and continuous-time $\Delta\Sigma$ T-D readout to address the trade-off between SNR, accuracy and power consumption. The driver delivers 200$\mu$App with $\leq$0.14% THD while consuming 80.3$\mu$A. Using a 6MHz clock, the readout achieves 53.6ps effective timing resolution at a 4k$\Omega$ load (0.1-4Hz noise integration). The IC achieves 96.1dB peak SNR, 99.8% magnitude accuracy and 0.13$^{\circ}$ phase error at a maximum power consumption of 140.5$\mu$W.