Abstract
The goal of this work is to use TSMC 0.18μm CMOS process to implement a PLL-based frequency synthesizer with a monolithic LC-tank voltage-controlled oscillator. The building blocks include phase frequency detector, charge pump, loop filter, voltage-controlled oscillator and programmable divider. A new structure that can generate higher negative resistance is proposed. We use this new negative resistance circuit to implement LC-tank voltage-controlled oscillator. The simulated negative resistance of this new structure is -259.8 Ω. The simulated negative resistance of conventional structure is -152.7Ω. . It allows the circuit to take less time to become oscillation. A quadrature oscillator is also implemented by this new negative resistance circuit. It can support quadrature outputs without any digital circuit. The simulated negative resistance of the new structure is -272.1 Ω. The simulated negative resistance of conventional structure is -141.5Ω. In addition, a new low flicker noise transistor layout is proposed. It can reduce the effect of flicker noise for phase noise. Better phase noise of a monolithic LC-tank voltage-controlled oscillator is obtained.