Summary: | 碩士 === 國立臺灣科技大學 === 電子工程系 === 96 === Chapter four presents a low power Colpitts injection locked frequency divider (ILFD) based on the all-NMOS Colpitts VCO topology. The all-nMOS ILFD uses an internal feedback so that the VCO can operate at the low power mode. At the supply voltage of 1.4 V, the tuning range of the free running ILFD is from 3.05 GHz to 3.16 GHz, about 110 MHz while the tuning voltage is tuned from 0 V to 1.4 V. At the injection signal power of 0 dBm, the total locking range of the ILFD in the divide-by-2 (-4) mode is from 5.78 to 6.6 (12.1 to 12.75) GHz, about 0.82 (0.65) GHz. The ILFD dissipates 2.6 mW at the supply voltage of 1.4 V and was fabricated in the 1P6M 0.18 μm CMOS process. The phase noise of the locked ILFD tracks with the low-phase-noise injection source.
Chapter five presents a 5.2GHz, 0.43V voltage-controlled oscillator (VCO) designed and implemented in a 0.18 μm CMOS 1P6M process. The designed circuit topology consists of two parallel LC resonators in series with the gates of negative differential resistance transistors. At the supply voltage of 0.43 V, the output phase noise of the VCO is -116 dBc/Hz at 1MHz offset frequency from the carrier frequency of 5.3 GHz, and the figure of merit is -187.8dBc/Hz. Total VCO core power consumption is 1.8275 mW. Tuning range is about 715 MHz, from 5.41 to 4.826 GHz, while the control voltage was tuned from 0 V to 1.2 V.
Chapter six shows a new differential Colpitts voltage-controlled oscillator (VCO) designed and implemented in a 0.13 μm CMOS 1P8M process. The designed circuit topology consists of all-nMOS Colpitts LC-tank VCOs, and the forward-biased body-source junction diode is used to enhance the VCO performance. At the supply voltage of 1.0 V, the output phase noise of the VCO is -113.8 dBc/Hz at 1MHz offset frequency from the carrier frequency of 13.64 GHz, and the figure of merit is -191.3 dBc/Hz. Total power consumption is 3.3 mW. Tuning range is about 270 MHz, from 13.63 to 13.9 GHz, while the control voltage was tuned from 0 V to 1.0 V.
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