Modeling of MOS varactors and characterizing the tuning curve of a 5-6 GHz LC VCO

Author

Sameni, Pedram ; Siu, Chris ; Iniewski, Krzysztof ; Hamour, Marwa ; Mirabbasi, Shahriar ; Djahanshahi, Hormoz ; Chana, Jatinder

Author_Institution

Dept. of Electr. & Comput. Eng., British Columbia Univ., Vancouver, BC, Canada

fYear

2005

fDate

23-26 May 2005

Firstpage

5071

Abstract

A novel accumulation-mode MOS varactor model used for characterizing the tuning curve of LC-tank voltage-controlled oscillators (VCOs) is presented. The VCO tuning characteristic is seen to depend not only on the C-V characteristics of the varactor but also on losses in the tank. Effects of variations in the tank quality factor (Q) and oscillator´s swing on the VCO tuning curve are discussed. Also a practical SPICE model using a pMOS transistor to describe an accumulation-mode MOS varactor is proposed. The model has been verified in a number of structures manufactured in a standard 0.13 μm CMOS process and is suitable for simulation within many circuit design environments.

Keywords

CMOS analogue integrated circuits; Q-factor; capacitance; circuit tuning; integrated circuit design; semiconductor device models; varactors; voltage-controlled oscillators; 5 to 6 GHz; CMOS process; LC VCO; LC-tank voltage-controlled oscillators; Q-factor; SPICE model; accumulation-mode MOS varactor model; circuit design; pMOS transistor; quality factor; tuning characteristic; tuning curve; Capacitance-voltage characteristics; Circuit optimization; MOSFETs; Manufacturing processes; Q factor; SPICE; Semiconductor device modeling; Tuning; Varactors; Voltage-controlled oscillators;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 2005. ISCAS 2005. IEEE International Symposium on

Print_ISBN

0-7803-8834-8

Type

conf

DOI

10.1109/ISCAS.2005.1465774

Filename

1465774