Title :
An Integrated 5–2.5-GHz Direct-Injection Locked Quadrature LC VCO
Author :
Jang, S.-L. ; Chuang, Y.-H. ; Lee, S.-H. ; Chi, L.-R. ; Lee, C.-F.
Author_Institution :
Dept. of Electron. Eng., Nat. Taiwan Univ. of Sci. & Technol., Taipei
Abstract :
This letter presents an integrated direct-injection locked quadrature voltage controlled oscillator (VCO), consisted of a 5-GHz VCO integrated with injection locked LC frequency dividers for low-power quadrature generation. The circuit is implemented using a standard 0.18-mum CMOS process. The differential VCO is a full PMOS Colpitts oscillator, and the frequency divider is performed by adding an injection nMOS between the differential outputs of complementary cross-coupled np-core LC VCO. The measurement results show that at the supply voltage of 1.8-V, the master 5-GHz VCO is tunable from 4.73 to 5.74GHz, and the slave 2.5-GHz VCO is tunable from 2.36 to 2.87GHz. The measured phase noise of master VCO is -118.2dBc/Hz while the locked quadrature output phase noise is -124.4dBc/Hz at 1-MHz offset frequency, which is 6.2dB lower than the master VCO. The core power consumptions are 7.8 and 8.7mW at master and slave VCOs, respectively
Keywords :
CMOS integrated circuits; MMIC oscillators; UHF oscillators; frequency dividers; injection locked oscillators; 0.18 micron; 1.8 V; 2.36 to 2.87 GHz; 4.73 to 5.74 GHz; 7.8 mW; 8.7 mW; CMOS process; Colpitts oscillator; VCO; injection-locked frequency divider; locking range; microwave oscillators; quadrature generation; voltage controlled oscillators; CMOS process; Frequency conversion; Frequency measurement; Injection-locked oscillators; MOS devices; Master-slave; Phase noise; Tunable circuits and devices; Voltage; Voltage-controlled oscillators; CMOS; injection-locked frequency divider (ILFD); low-voltage; quadrature generation; wide locking range;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2006.890343
