Patent ID: 7535308

Claim:
A voltage-controlled oscillator comprising: an inductor-capacitor bank supplied with a power source voltage and a control voltage, wherein the inductor-capacitor bank oscillates first and second oscillation nodes from which first and second oscillation signals are generated, respectively; a negative resistor circuit including first and second control nodes and first and second transistors which provide negative resistance to the inductor-capacitor bank, wherein the negative resistor circuit maintains the oscillation of the first and second oscillation nodes; a direct current block which couples the second oscillation node with the first control node and couples the first oscillation node with the second control node, wherein the first control node controls the first transistor and the second control node controls the second transistor; an alternating current block including a source resistor disposed between a junction node, which is connected to the first and second transistors, and a ground voltage; a first bias circuit controlled by the junction node, wherein the first bias circuit provides a first feedback voltage to the first control node and maintains a voltage at the junction node of the first and second transistors; and a second bias circuit controlled by the junction node, wherein the second bias circuit provides a second feedback voltage to the second control node and maintains a voltage at the junction node of the first and second transistors.