Title :
Analysis of oscillator amplitude control, and its application to automatic tuning of quality factor for active LC filters
Author :
Li, Shaorui ; Tsividis, Yannis
Author_Institution :
Dept. of Electr. Eng., Columbia Univ., New York, NY, USA
Abstract :
This paper presents an analytical solution to the amplitude control of the Q-enhanced LC resonator. It is shown that due to the nonlinearity of the active devices, effective amplitude control is realizable by a conventional magnitude-locked-loop, and that it is applicable to the automatic quality factor tuning of active LC filters. The effects of the weak nonlinearity magnitude and the amplitude used in the reference resonator on the achieved Q of filter resonator(s) is discussed. The results are verified by simulations and breadboard experiments.
Keywords :
MOSFET; Q-factor; active filters; circuit tuning; resonator filters; semiconductor device models; Q-enhanced LC filter resonator; active LC filters; active devices; automatic tuning quality factor; magnitude locked loop; oscillator amplitude control; Active filters; Active inductors; Automatic control; Oscillators; Q factor; Resonant frequency; Resonator filters; Spirals; Steady-state; Tuning;
Conference_Titel :
Circuits and Systems, 2004. ISCAS '04. Proceedings of the 2004 International Symposium on
Print_ISBN :
0-7803-8251-X
DOI :
10.1109/ISCAS.2004.1328960
