JSSC 2014第11期Analog Circuits65nm

Analysis and Design of a High-Order Discrete-Time Passive IIR Low-Pass Filter Ma

提出一种基于电荷共享旋转的高阶离散时间无源IIR低通滤波器，支持电压采样和电荷采样模式。

65nm CMOS, 1.2V, 800MS/s, 400kHz-30MHz带宽, 100dB阻带抑制, +21dBm IIP3, 4.57nV/√Hz噪声, 2mW功耗, 0.42mm²面积

离散时间滤波器IIR低通滤波器电荷共享无源设计纳米CMOS

▸创新点1：采用电荷共享旋转技术实现高阶滤波，通过电容和开关的巧妙组合，避免了传统高阶滤波器对复杂运算放大器的依赖，显著降低了功耗和面积。

▸创新点2：通过流水线技术提升采样率至800 MS/s，有效解决了高阶滤波器在高速采样下的性能瓶颈，同时保持了较低的功耗和噪声水平。

▸创新点3：兼容数字纳米技术，使用开关、电容和简单的gm-cell，而非传统运算放大器，使得滤波器能够在纳米级CMOS工艺中高效实现，适应现代集成电路的发展趋势。

▸创新点4：滤波器带宽可编程范围为400 kHz至30 MHz，最大阻带抑制达到100 dB，IIP3为+21 dBm，平均点噪声为4.57 nV/√Hz，在1.2 V电压下仅消耗2 mW，面积仅为0.42 mm²，展现了卓越的综合性能。

Abstract

In this paper , we propose a discrete-time IIR low-pass ﬁlter that achieves a high-order of ﬁltering through a charge-sharing rotation. Its sampling rate is then multiplied through pipelining. The ﬁrst stage of the ﬁlter can operate in either a voltage-sampling or charge-sampling mode. It uses switches, capacitors and a simpl eg m - c e l l ,r a t h e rt h a no p a m p s , thus being compatible with digit al nanoscale technology. In the voltage-sampling mode, the gm-cell is bypassed so the ﬁlter