Translinearized broadband lc-type voltage-controlled oscillator and adjustable capacitor array circuit

Abstract

The invention discloses a transwire linearized wideband LC type voltage controlled oscillator and an adjustable capacitor array circuit; a transwired linearized broadband LC type voltage controlled oscillator includes an LC oscillating circuit and an adjustable capacitor array circuit 1; its features In that: the LC oscillating circuit includes a PMOS transistor 1, a PMOS transistor 2, a three-terminal differential inductor 1 and a bias circuit; the gate of the PMOS transistor 1 is connected to the drain of the PMOS transistor 2 through an AC coupling capacitor 1, and the PMOS transistor 2 The gate of PMOS transistor 1 is connected to the drain of PMOS transistor 1 through AC coupling capacitor 2; the symmetrical ends of three-terminal differential inductor 1 are respectively connected to the gate of PMOS transistor 1 and the gate of PMOS transistor 2, and the middle of three-terminal differential inductor 1 The tap end is connected to a bias circuit; the adjustable capacitor array circuit one is connected in parallel with symmetrical two ends of the three-terminal differential inductor one; the invention can be widely used in various high-frequency local oscillator phase-locked loop systems.

Description

technical field [0001] The invention relates to an LC-type voltage-controlled oscillator, in particular to a transwire linearized broadband LC-type voltage-controlled oscillator and an adjustable capacitor array circuit. Background technique [0002] The voltage-controlled oscillator is an important part of the phase-locked loop, which is used to provide the local oscillator frequency and form the phase-locked loop loop. The core part of the voltage-controlled oscillator is usually composed of an active transconductance device and a resonant circuit, and the resonant circuit forms an oscillation through feedback. The active transconductance device is used to compensate the energy loss of the resonant tank oscillation, so as to generate a continuous and stable oscillation signal. As the core of the phase-locked loop, the voltage-controlled oscillator plays the role of providing the local oscillator frequency. Its oscillation frequency is proportional to its control voltage. ...

AI Technical Summary

Problems solved by technology

The traditional LC-type voltage-controlled oscillator usually cross-couples the gate and drain of the MOS device to form an active transconductance device. Since the oscillation signal swing of the LC-type voltage-controlled oscillator is usually close to or even exceeds the power supply voltage, this makes the Under large-signal working conditions, within the oscillation frequency cycle, the MOS device works in the triode region for nearly half of the cycle, showing transconductance nonlinear characteristics, and cannot obtain good phase noise characteristics

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