A high-frequency low-power sinusoidal quadrature oscillator using only CMOS current mirrors

Abstract

A high-frequency low-power sinusoidal quadrature oscillator is presented through a new technique using only CMOS current mirrors. The technique is relatively simple based on (1) internal capacitances of CMOS current mirrors and (2) a resistor of a CMOS current mirror for a negative resistance. No external capacitances or inductances are required. As a particular example, a 3.02-GHz, 0.4-f/sub T/, 0.31-mW, CMOS sinusoidal quadrature oscillator has been demonstrated. The oscillation frequency (f/sub 0/) is 3.02 GHz. The ratio of (f/sub 0//f/sub T/) is 0.4. The power consumption is low at approximately 0.31 mW. Total harmonic distortions (THD) are less than 0.3%. The oscillation frequency is current-tunable over a range of 660 MHz or 21.85%. The amplitude matching and the quadrature phase matching are better than 0.029 dB and 0.15/spl deg/, respectively. A figure of merit called CNR/sub norm/ is 161.68 dBc/Hz at the 2 MHz offset from 3.02 GHz. Comparisons to other approaches are also presented.