Endgate LLC

Endwave Corporation

Mark J Vaughan

Clifford A Mohwinkel

Edward Bryant Stoneham

Mark V Faulkner

A via termination for a microstrip transmission line formed on a substrate includes a termination resistor that connects an end of the signal conductor to a backside ground plane through a via. Two open-circuit stubs are also formed on the first face of the substrate, one stub on each side of the termination resistor. A compensation resistor on the first face of the substrate connects the end of the signal conductor to each open-circuit stub. The load resistor is equal to the characteristic impedance of the transmission line and the compensation resistors are each equal to twice the characteristic impedance. The combined termination ideally exhibits a real impedance equal to the characteristic impedance over a wide frequency range.

Impedance-compensating circuit

A means of connecting a plurality of essentially identical active devices is presented for the purpose of multifunction and multiple function operation. These devices, mounted on a chip, are flip-mounted onto a circuit formed on a base substrate and having large passive elements. Push-pull amplifiers are presented as examples in which the multiple function operation is the combining of amplifiers whose active devices are on a single chip. Electromagnetic coupling, impedance matching and signal transmission are variously provided by the use of strip lines, slotlines, coplanar waveguides, and a slotline converted into a coplanar waveguide.

Push-pull amplifier with dual coplanar transmission line

Two or three conductor coplanar transmission lines and lossy coplanar resistive films are formed on a surface of a substrate. The resistive film dimensions and resistivity are selected to suppress various spurious electromagnetic modes within and around the substrate. The resistive films may be positioned along the outer edges of the transmission lines or between the transmission line conductors. The resistive film may have regular spaced openings for producing an average resistivity different than that of a continuous resistive film. In one embodiment, a signal conductor has a serpentine shape and resistive film elements are positioned between adjacent sections of the signal conductor. In another embodiment, interdigitated resistive film elements extend between transmission line conductors.

Growing community of inventors

San Jose, CA, United States of America

Mark J Vaughan