Patent ID: 6304152
Filing Date: 2001-10-16
Classification: H03B,H03J

Abstract:
A digital-control Colpitts oscillator circuit having: a transistor amplifier; a first capacitor connected between an output of said transistor amplifier and a control electrode of said transistor amplifier; a second capacitor connected between said output of said transistor amplifier and an AC-ground potential; and an oscillator element connected between said control electrode of said transistor amplifier and said AC-ground potential; said first capacitor, said second capacitor and said oscillator element making up a parallel resonance circuit, and an equivalent capacitance of said first capacitor and said second capacitor connected in series through said output of said transistor amplifier being variable under the condition that the ratio of the capacitance of said first capacitor to that of said second capacitor is kept unchanged at a prescribed value.