A 140.5$μ$W, 99.8% Accuracy, 96.1dB SNR BioZ IC for Real-Time Cell Analysis with On-Demand Push-Pull Excitation and Continuous-Time $ΔΣ$ T-D Readout

This paper presents a bioimpedance IC combining an on-demand push-pull driver and continuous-time $ΔΣ$ T-D readout to address the trade-off between SNR, accuracy and power consumption. The driver delivers 200$μ$App with $\leq$0.14% THD while consuming 80.3$μ$A. Using a 6MHz clock, the readout achieves 53.6ps effective timing resolution at a 4k$Ω$ 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$μ$W.