Patent ID: 11211898

Abstract:
Disclosed is an integrated circuit amplifier for use in a crystal oscillator. The circuit amplifier comprises a transistor; a voltage dependent capacitance circuit; and a node. The voltage dependent capacitance circuit comprises a device with a voltage dependent capacitance and a bias circuit. The node is connected to a terminal of the transistor and the integrated circuit amplifier is configured such that an intrinsic capacitance of the transistor is dependent on the mean voltage at the node. The node is connected to a terminal of the voltage dependent capacitance circuit and the integrated circuit amplifier is configured such that an effective capacitance of the node is dependent on the intrinsic capacitance of the transistor and the voltage dependent capacitance of said device. When in use, the voltage dependent capacitance circuit reduces the amount of change of the effective capacitance of the node when the mean voltage at the node changes.