A novel nonlinear settling model of OTA for high-resolution switched-capacitor sigma-delta modulator design

Author

Shi, Chunlei ; Li, Xiaopeng ; Ismail, Mohammed

Author_Institution

Dept. of Electr. Eng., Ohio State Univ., Columbus, OH, USA

fYear

1999

fDate

22-24 Nov. 1999

Firstpage

47

Lastpage

50

Abstract

A novel nonlinear settling model of OTAs in SC integrators is presented. Using this accurate model, the requirement for OTAs in high-resolution sigma-delta modulator A/D converters is relaxed. Firstly, a signal-dependent nonlinear settling time constant is derived based on the circuit-level analysis. Then, a modified nonlinear settling algorithm is proposed by including the obtained nonlinear settling time constant. Finally, a high resolution fourth-order cascaded sigma-delta modulator is simulated and results are compared with other approaches.

Keywords

cascade networks; integrated circuit modelling; operational amplifiers; sigma-delta modulation; switched capacitor networks; OTA; SC integrators; circuit-level analysis; fourth-order cascaded sigma-delta modulator; high-resolution sigma-delta modulator A/D converters; model; modified nonlinear settling algorithm; nonlinear settling model; nonlinear settling time constant; signal-dependent nonlinear settling time constant; simulation; switched-capacitor sigma-delta modulator design; Circuit analysis; Circuit simulation; Delta-sigma modulation; Energy consumption; Intensity modulation; Signal analysis; Signal processing algorithms; Signal resolution; Switches; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Microelectronics, 1999. ICM '99. The Eleventh International Conference on

Print_ISBN

0-7803-6643-3

Type

conf

DOI

10.1109/ICM.2000.884802

Filename

884802