A Low-Phase Noise and High Output Swing RF LC-VCO in CMOS Technology

• Published in: 2006 International RF and Microwave Conference pp. 197 - 200
• Main Authors: Ramiah, H., Zulkifli, T.Z.A.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01-09-2006
• Subjects: Circuit optimization; CMOS process; CMOS technology; Inductors; LC-tank; Measurement standards; Open drain buffer; Phase noise; Radio frequency; RF CMOS; Varactors; Voltage controlled oscillator (VCO); Voltage-controlled oscillators; Wireless LAN
• ISBN: 0780397444; 9780780397446
• DOI: 10.1109/RFM.2006.331068

This paper presents the design of a 1.8-V, 3.5GHz CMOS complementary cross-coupled LC-VCO designed for WLAN IEEE 802.11a, two step frequency up-conversion applications with integrated stacked planar inductor. The tuning range of the VCO spans from 3.38 GHz to 3.55 GHz achieved through a depletion mode pMOS based varactor and the corresponding core circuit current consumption is 2.5mA. Implemented in a 0.18mum standard CMOS process the VCO is integrated with a high gain cross-coupled open drain buffer and measures a close in 1/f 3 phase noise of -57 dBc/Hz at 10 kHz of offset frequency. The far out phase noise, 1/f 2 is -116 dBc/Hz at 1 MHz of offset frequency