Implementation of a multi-band Voltage-Controlled Ring Oscillator Using 0.18 um CMOS

• Main Authors: Kuo-Wei Cheng, 鄭國偉
• Other Authors: Mu-Huo Cheng
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/g9689y

碩士 === 國立交通大學 === 電機與控制工程系所 === 93 === This thesis presents a multi-band voltage-controlled ring oscillator via the multiple-pass connection, resulting in a wide range of oscillation frequency. Most multiple-pass ring oscillators are designed to increase the oscillation frequency. In this thesis, we also exploit the concept of multiple-pass to design a multiple-pass ring oscillator which can decrease the oscillation frequency. A connection is designed via the NMOS switch to combine together the two circuits all via the concept of multiple-pass such that a wider range of oscillation frequency can be obtained. Hence, we obtain a voltage-controlled oscillator with two frequency bands which can be easily controlled by the on/off of the NMOS switches. We design a nine-stage ring oscillator; each stage consists of twelve MOS transistors including eight NMOS transistors and four PMOS transistors. This oscillator is simulated using 0.18 $\mu m,$ 1P6M CMOS technology provided by Taiwan Semi-Conductor Manufacturing Company. The post simulation of the design oscillator, under the supply voltage of 1.8 V, shows that the required power is 91.4 mw, the phase noise is -115.8 dBc/Hz at a 1-MHz offset from a 2-GHz center frequency, the frequency tuning range is from 0.32GHz to 1.8GHz, and the minimum peak-to-peak output swing is 1.67V.