An RF CMOS Q-Enhanced LC Resonator

Abstract

This paper investigates a Q-enhanced LC resonator implemented with a Q-enhancement circuit based on both active and reactive components. An analytical expression is presented for the Q-enhancement circuit and simulations are compared with measurements on a differential Q-enhanced LC tank operating at 1779-1870 MHz. Sensitive circuits and inaccurate models leads to inaccurate simulations. To improve the accuracy of simulations, S-parameter measurements of components and sub-circuits are included in the simulations whereby an accuracy of 3 MHz in the estimate of the resonator center frequency results.