This brief presents a power-efficient quadrature signal generator and current driver application-specific integrated circuit (ASIC) for bioimpedance measurements in an electrical impedance tomography system for monitoring lung function. The signal generator is realized by a digital recursive signal oscillator with the ability of generating quadrature signals over a wide frequency range. The generated in-phase signal is applied to a current driver. It uses a balanced current-mode feedback architecture that monitors the output current through a feedback loop to minimize common-mode voltage build-up at the injection site. The quadrature signals can be used for I/Q demodulation of the measured bioimpedance. The ASIC was designed in TSMC 65 nm technology occupying an area of 0.21 mm2. The current driver can generate up to 0.7 mA $_{\text {p-p}}$ current up to 200 kHz and consumes 2.7 mW power using ±0.8 V supplies.

中文翻译：

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用于生物阻抗应用的低功耗递归 I/Q 信号发生器和电流驱动器

本简介介绍了一种用于监测肺功能的电阻抗断层扫描系统中的生物阻抗测量的高能效正交信号发生器和电流驱动器专用集成电路 (ASIC)。信号发生器由具有在宽频率范围内产生正交信号的能力的数字递归信号振荡器实现。产生的同相信号被施加到电流驱动器。它使用平衡电流模式反馈架构，通过反馈环路监控输出电流，以最大限度地减少注入部位的共模电压累积。正交信号可用于测量的生物阻抗的 I/Q 解调。ASIC 采用台积电 65 纳米技术设计，面积为 0.21 平方毫米。电流驱动器可产生高达 0.7 mA $_{\文本{pp}}$电流高达 200 kHz，使用 ±0.8 V 电源消耗 2.7 mW 功率。