Patent ID: 10250188

Abstract:
A voltage controlled oscillator includes a resonance unit, coupling unit and source degeneration unit. The resonance unit includes two first inductors and two first variable capacitors. The first inductor is electrically connected to the first variable capacitor. The coupling unit includes a first transistor and a second transistor. Power supply input terminals of the first and second transistors are electrically connected to the resonance unit. The source degeneration unit includes two adjustable inductors, two fourth inductors and two second variable capacitors. The adjustable inductors are connected to power supply output terminals of the first and second transistors, respectively. The second variable capacitor is electrically connected to the adjustable inductor and the fourth inductor, wherein equivalent inductance of the adjustable inductor is adjusted, such that input impedance looking in the direction away from the resonance unit from the power supply input terminal is featured by negative capacitance.