Patent ID: 7196592
Filing Date: 2007-03-27
Classification: H03B,H03L

Abstract:
1. A voltage-controlled oscillator circuit, comprising: a pair of inductors coupled to a first power source; a variable resistor; a pair of capacitors respectively coupled between the variable resistor and the pair of inductors in serial; a pair of first switches respectively coupled between the pair of capacitors and a second power source, wherein the first switch of the pair comprises a first gate coupled to a connection point of the other first switch and the corresponding capacitor; and an amplitude control circuit having a peak detector having a first input terminal coupled to a connection point of the capacitor and the corresponding inductor, and a first output terminal, wherein a voltage level of the first output terminal tracks that of the first input terminal; and a second switch coupled between the first control gates of the first switches, having a second gate coupled to a second output terminal.