A chopper amplifier with a low duty‐cycle sub‐sampling in the switched‐capacitor integrator for noise reduction-Reference-Cited by-同舟云学术

A chopper amplifier with a low duty‐cycle sub‐sampling in the switched‐capacitor integrator for noise reduction

Published:2023-04 Issue:7 Volume:59 Page:
ISSN:0013-5194
Container-title:Electronics Letters
language:en
Short-container-title:Electronics Letters

Author:

Mu Geng¹²^ORCID,Lyu Liangjian³,Ye Dawei⁴^ORCID,Richard Shi C.‐J.⁵

Affiliation:

1. Fudan University Shanghai China

2. State Key Laboratory of ASIC and System Fudan University Shanghai People's Republic of China

3. East China Normal University Shanghai China

4. Huazhong University of Science and Technology Wuhan China

5. University of Washington Washington Seattle USA

Abstract

AbstractThis letter presents a low‐noise implementation of the switched‐capacitor (SC) DC servo loop (DSL) in the capacitively coupled chopper instrumentation amplifier (CCIA). The noise of the SC integrator in SC DSL is first analyzed, then a low duty‐cycle subsampling and unbalanced capacitor ratio are proposed to reduce the noise. Fabricated in a 65‐nm complementary metal‐oxide semiconductor (CMOS) process, the CCIA achieves 2.5 μVrms input‐referred noise, integrated from 0.5 to 250 Hz, and 110‐mV electrode‐DC offset (EDO) cancellation range. Besides, the calculated noise of the SC integrator well matches the measured, which proves the noise analysis. Compared with prior designs adopting similar SC integrators, this work reduces the noise level by 2× and increases the cancellation range by 2×.

Funder

Science and Technology Commission of Shanghai Municipality

Publisher

Institution of Engineering and Technology (IET)

Subject

Electrical and Electronic Engineering

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