Premium
Low‐phase‐noise CMOS VCO with harmonically tuned LC tank
Author(s) -
Chung Yujin,
Lee JongRyul,
Kim Bumman
Publication year - 2004
Publication title -
microwave and optical technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 76
eISSN - 1098-2760
pISSN - 0895-2477
DOI - 10.1002/mop.20240
Subject(s) - voltage controlled oscillator , phase noise , dbc , lc circuit , electrical engineering , offset (computer science) , voltage , cmos , materials science , noise (video) , microwave , engineering , optoelectronics , electronic engineering , capacitor , telecommunications , computer science , artificial intelligence , image (mathematics) , programming language
A low‐phase‐noise voltage‐controlled oscillator (VCO) has been demonstrated using a harmonically tuned LC resonance tank. In this circuit configuration, the voltage shape at the differential cell is almost rectangular; thus, the cell is switched effectively and the phase noise is reduced. More importantly, the proposed tank suppresses down‐conversion of the noise around 2f 0 to the phase noise, due to the 2 nd harmonic short of the tank. Therefore, the phase noise of the VCO based on the tank is improved considerably. The VCO for 1‐GHz operation has been realized using a 0.35‐μm CMOS process. It shows a phase noise of −111.6 dBc/Hz at 100 KHz offset, which is a 5.7‐dB improvement over a comparable standard VCO. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 164–167, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20240