A CMOS Quadrature VCO With Subharmonic and Injection-Locked Techniques

• Published in: IEEE transactions on circuits and systems. II, Express briefs Express briefs, 2010-11, Vol.57 (11), p.843-847
• Main Authors: Lee, Shuenn-Yuh, Wang, Liang-Hung, Lin, Yu-Heng
• Format: Article
• Language: English
• Subjects: CMOS; CMOS integrated circuits; Electric potential; Frequency doubled; Frequency measurement; injection locked; Noise; oscillator; Phase noise; Power consumption; quadrature; Quadratures; radio-frequency complementary metal-oxide-semiconductor (RF CMOS); Resonant frequency; subharmonic; Tanks; Tuning; Voltage; voltage-controlled oscillator (VCO); Voltage-controlled oscillators
• ISSN: 1549-7747; 1558-3791
• DOI: 10.1109/TCSII.2010.2082990

A 1-V quadrature voltage-controlled oscillator (QVCO) using subharmonic and injection-locked techniques (SHIL-QVCO) is presented. Instead of using the traditional transformer-coupling LC tank with a large area to implement the quadrature output, we use a frequency-doubled differential pair with an injection-locked method. The proposed QVCO is implemented with a TSMC 0.18- μm 1P6M CMOS process having a 1.4 × 0.67 × mm 2 chip area. This QVCO has the advantages of low phase noise and low power consumption. Experimental results show that the QVCO has a phase noise of - 126 dBc/Hz at an offset frequency of 1 MHz and a power consumption of 4.9 mW to achieve a 186 figure of merit. Moreover, a tuning frequency between 2.17 and 2.52 GHz can be obtained with a tuning voltage range of 0-1 V for the IEEE 802.15.4.