Analysis and Optimization of SFDR in Differential Active-RC Filters

Author

Meghdadi, Masoud ; Bakhtiar, M. Sharif

Author_Institution

Dept. of Electr. Eng., Sharif Univ. of Technol., Tehran, Iran

Volume

59

Issue

6

fYear

2012

fDate

6/1/2012 12:00:00 AM

Firstpage

1168

Lastpage

1177

Abstract

This paper presents a method for optimizing SFDR in differential active-RC filters. Simple analytical expressions for noise and third-order intermodulation (IM3) distortion in active-RC filters are derived. The nonlinear behavior of two-stage Miller-compensated op amps, which are extensively used in active-RC implementations, is also modeled. These expressions and models are used to maximize SFDR in active-RC filters by means of proper admittance scaling and optimizing the share of each op amp in the total power consumption. It is shown that both the power consumption of the filter and its area can be significantly reduced, for a given SFDR, by exploiting the presented method.

Keywords

RC circuits; active filters; circuit optimisation; intermodulation distortion; operational amplifiers; IM3 distortion; SFDR optimization; admittance scaling; differential active-RC filters; nonlinear behavior; spurious free dynamic range; third-order intermodulation distortion; total power consumption; two-stage Miller-compensated operational amplifier; Linearity; Noise; Nonlinear distortion; Operational amplifiers; Optimization; Prototypes; Transfer functions; Active-RC filters; IIP3; Miller-compensated op amps; SFDR optimization; channel selection; low power; noise; phase margin; scaling; third-order intermodulation (IM3);

fLanguage

English

Journal_Title

Circuits and Systems I: Regular Papers, IEEE Transactions on

Publisher

ieee

ISSN

1549-8328

Type

jour

DOI

10.1109/TCSI.2011.2173388

Filename

6112188