| 主权项 |
1. A voltage controlled oscillator comprising:
a plurality of serially connected composite gain stages, a composite gain stage of the plurality of serially connected composite gain stages comprising:
a transconductance stage having first and second current paths from a first power supply voltage terminal to a second power supply voltage terminal, each of the first and second current paths having an input terminal and an output terminal, and a first variable resistance coupled between the first and second current paths, the first variable resistance responsive to a first, fine tune control signal that adjusts a frequency of the voltage controlled oscillator during operation of the voltage controlled oscillator, wherein the fine tune control signal is generated based on a determination of whether an output signal from the voltage controlled oscillator leads or lags a reference signal; anda transimpedance stage having a first inverter and a second inverter, the first inverter having an input terminal coupled to the output of the first current path and an output terminal, the second inverter having an input terminal coupled to the output of the second current path, and an output terminal, a second variable resistance coupled between the input terminal and the output terminal of the first inverter, a third variable resistance coupled between the input terminal and the output terminal of the second inverter, the second and third variable resistances responsive to a second, coarse tune control signal that is generated based on the first, fine tune control signal, wherein the second, coarse tune control signal adjusts a frequency range of the voltage controlled oscillator until the frequency range is in a desired range. |
