Patent ID: 6731182
Filing Date: 2004-05-04
Classification: H03B,H03L

Abstract:
A voltage-controlled oscillator comprising:a resonant portion including at least one variable-capacitance device and at least one inductor, and a first capacitance device connected in parallel with the inductor, the capacitive device having an identical structure with the variable-capacitance device; an active portion including differential pair transistors and supplying electric power to the resonant portion in such a way as not to attenuate oscillation of the resonant portion; a current source connected to emitters or sources of both of the differential pair transistors, and is a circuit having a resistor and a second capacitive device connected in parallel; and wherein at least the variable-capacitance device included in the resonant portion, the active portion, and the current source are formed within a single semiconductor integrated circuit.