模拟滤波器在生理信号前端处理集成电路中是至关重要的模块，它直接影响到所获取的信号质量。由于生理信号的频率范围极低，模拟滤波器中大数值电容的片上实现是亟需解决的问题。总结了电容倍增电路的研究进展，对电流模式倍增电路、电压模式倍增电路、基于电流电压转换方式的电容倍增电路、非平衡电容倍增电路等关键技术进行了提炼和分析，并且展望了电容倍增电路未来的研究方向。
On-chip analog filter is a key part for integrated circuits preprocessing physiological signals, which influences the quality of signals acquired. Since the frequency of the physiological signals is of ultra-low range, the on-chip large capacitance in the analog filter is the key problem to be solved immediately. The paper summaries the recent progress of the capacitance multiplier development, such as current mode capacitance multiplier, voltage mode capacitance multiplier, capacitance multiplier based on current-to-voltage converter and unbalanced capacitance multiplier, and then analyzes the key technology. Finally the paper looks into the future of the capacitance multiplying circuits.
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