A 0.55V 61dB-SNR 67dB-SFDR 7MHz 4th-Order Butterworth Filter Using Ring-Oscillator-Based Integrators in 90nm CMOS

📋 论文概要

本文提出了一种基于环形振荡器积分器的4阶巴特沃斯滤波器，在0.55V低电压下实现了61dB SNR和67dB SFDR，带宽为7MHz，解决了传统OTA积分器在低电压下增益和带宽难以兼顾的问题。

💡 主要创新点

• 采用环形振荡器（ring oscillator）代替传统OTA实现积分器，避免了低电压下OTA增益和带宽的折衷，实现了低电压高性能滤波。
• 通过环形振荡器积分器构建4阶巴特沃斯滤波器，在0.55V供电下达到61dB SNR和67dB SFDR，同时保持7MHz带宽。
• 在90nm CMOS工艺中验证了该架构的可行性，为低电压模拟滤波器设计提供了新思路。

🏷 关键词

📄 原文摘要

Oregon State University, Corvallis, OR 1 2 Integrators are key building blocks in many analog signal processing circuits and systems. They are typically implemented using either an opamp-RC or a Gm-C architecture depending on bandwidth and linearity requirements. The performance of both these topologies depends on the operational transconductance amplifier (OTA) used to implement the integrator. Reduced supply voltage and lower transistor output impedance make it difficult to implement high-gain widebandwidth OTAs in a power-efficient manner. Consequently, the DC gain of the integrator is often severely limited when designed in deep-submicron CMOS processes. Conventional integrators employ multi-stage OTAs operating in weak inversion and forward body biasing to achieve large DC gain at low supply voltages [1]. These techniques require automatic biasing to guarantee robust operation under all conditions and the use of frequency compensation combined with

👥 作者与机构

Brian Drost1,2, Mrunmay Talegaonkar2, Pavan Kumar Hanumolu2

Silicon Laboratories, Corvallis, OR