Patent ID: 11888445
Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 22:
23. The system of claim 22, wherein for each variable capacitor device:
the first control path comprises the first transistor and at least one capacitor serially connected between a first terminal and a second terminal of the variable capacitor device;
the second control path comprises the second transistor and at least one capacitor serially connected between the first terminal and the second terminal of the variable capacitor device;
the first and second terminals of the variable capacitor device are coupled to the first and second tank nodes, respectively, of the resonant tank circuit; and
each variable capacitor device further comprises:
differential control terminals comprising a first control terminal and a second control terminal, wherein the first control terminal is coupled to a gate terminal of the first transistor, and the second control terminal is coupled to first and second source/drain terminals of the second transistor; and
a first tuning terminal and a second tuning terminal, wherein the first tuning terminal is coupled to first and second source/drain terminals of the first transistor, and the second tuning terminal is coupled to a gate terminal of the second transistor;

wherein the phase-locked loop system further comprises a calibration system configured to generate different sets of first and second reference voltages that are applied to respective first and second tuning terminals of two or more of the variable capacitor devices to adjust at least one of (i) a capacitance-to-differential voltage transfer characteristic of each of the two or more of the variable capacitor devices, and (ii) a ratio of a differential mode gain of the voltage-controlled oscillator to a common mode gain of the voltage-controlled oscillator.