Patent ID: 7881686

Claim:
A voltage-controlled capacitor comprising: a substrate assembly with an input terminal, a control terminal, and a voltage reference terminal; voltage reference lines disposed on the substrate assembly, wherein at least one of the voltage reference lines is coupled to the voltage reference terminal; a mechanical conductor membrane spaced above the substrate assembly and coupled directly or indirectly to one or more of the voltage reference lines at opposing ends of the mechanical conductor membrane so that the opposing mechanical conductor membrane is anchored at two or more ends and so that the mechanical conductor membrane is AC coupled to the one or more voltage reference lines, wherein at least a portion of the mechanical conductor membrane is movable to and from a first position a first distance from a surface of the substrate assembly and a second position a second distance from the surface of the substrate assembly; one or more posts disposed between the substrate assembly and the mechanical conductor membrane and disposed between the two or more ends anchoring the mechanical conductor membrane, where the one or more posts support the mechanical conductor membrane; a signal conductor disposed on the substrate assembly, where the signal conductor is DC coupled to the control terminal, wherein a voltage on the control terminal at least partially controls the position of the mechanical conductor membrane; a layer of dielectric material disposed between a top surface of the signal conductor and the mechanical conductor membrane, where a gap exists between at least one of (a) the mechanical conductor membrane and the layer of dielectric material or (b) the layer of dielectric material and the signal conductor when the mechanical conductor membrane is in the first position, and substantially no gap exists when the mechanical conductor membrane is in the second position; and a coupling capacitor with a first terminal and a second terminal, where the first terminal is coupled to the input terminal and where the second terminal is coupled to the signal conductor.