The research described in this thesis focuses on the design of a low power consumption and phase noise LC-VCO. With the current-reused topology, the proposed LC-VCO can operate using only half amount of DC current compared with the conventional topologies to achieve low power consumption. Here, we also propose to add an external resistor at the substrate node of the NMOS transistor, which reduces the substrate thermal noise of the NMOS transistor effectively and the phase noise of the LC-VCO as well. Based on proposed topology and novel method, we implement a low power and low phase noise dual-band LC-VCO, which operates at 2.5/3.5 GHz. The proposed dual-band LC-VCO is implemented by TSMC 0.18-μm 1P6M CMOS process and the measured results are similar to simulation ones. Therefore, the performances of the proposed LC-VCO achieve anticipation. The result shows that the phase noise reduction is about 7.0 dB and 4.0 dB at 10-kHz and 1-MHz offset frequency, respectively. With only 1.3 V bias voltage and 3.12 mW power consumption, the proposed LC-VCO operates 2.5 GHz and 3.5 GHz with phase noise of -121 dBc/Hz and -117 dBc/Hz, respectively, at 1 MHz offset frequency.
A 2.4/5 GHz dual-band VCO using a variable inductor and switched resonator / Kao, H. L.;Yang, D. Y.;Chin, Albert;McAlister, S. P.