A precise 90° quadrature OTA-C oscillator tunable in the 50-130-MHz range

Author

Linares-Barranco, Bernabé ; Serrano-Gotarredona, Teresa ; Ramos-Martos, Juan ; Ceballos-Cáceres, Joaquín ; Mora, José Miguel ; Linares-Barranco, Alejandro

Author_Institution

Inst. de Microelectron. de Sevilla, Seville, Spain

Volume

51

Issue

4

fYear

2004

fDate

4/1/2004 12:00:00 AM

Firstpage

649

Lastpage

663

Abstract

We present a very-large-scale integration continuous-time sinusoidal operational transconductance amplifiers quadrature oscillator fabricated in a standard double-poly 0.8-μm CMOS process. The oscillator is tunable in the frequency range from 50 to 130 MHz. The two phases produced by the oscillator show a low-quadrature phase error. A novel current-mode amplitude control scheme is developed that allows for very small amplitudes. Stability of the amplitude control loop is studied as well as design considerations for its optimization. Experimental results are provided.

Keywords

VLSI; operational amplifiers; optimisation; oscillators; phase noise; quadrature amplitude modulation; 50 to 130 MHz; VLSI; analog very large-scale integration; continuous-time sinusoidal operational transconductance amplifiers quadrature oscillator; current-mode amplitude control; gmC; impedance probe; low-quadrature phase error; multiphase oscillators; oscillator stability; phase noise; quadrature OTA-C oscillator tunable; quadrature oscillators; sinusoidal oscillators; standard double-poly; transconductance-capacitance oscillators; very-large-scale integration; Bridge circuits; Frequency; Impedance measurement; Operational amplifiers; Oscillators; Probes; Soil; Transconductance; Tunable circuits and devices; Very large scale integration;

fLanguage

English

Journal_Title

Circuits and Systems I: Regular Papers, IEEE Transactions on

Publisher

ieee

ISSN

1549-8328

Type

jour

DOI

10.1109/TCSI.2004.823673

Filename

1284740