Abstract: A tunable capacitance circuit comprises a plurality of varactor transistors which are coupled in series. An antenna tuner comprises such a tunable capacitance circuit.

Abstract: A semiconductor torsional micro-electromechanical (MEM) switch is described having a conductive movable control electrode; an insulated semiconductor torsion beam attached to the movable control electrode, the insulated torsion beam and the movable control electrode being parallel to each other; and a movable contact attached to the insulated torsion beam, wherein the combination of the insulated torsion beam and the control electrode is perpendicular to the movable contact. The torsional MEM switch is characterized by having its control electrodes substantially perpendicular to the switching electrodes. The MEM switch may also include multiple controls to activate the device to form a single-pole, single-throw switch or a multiple-pole, multiple-throw switch. The method of fabricating the torsional MEM switch is fully compatible with the CMOS manufacturing process.

Abstract: An electronic system 8 is disclosed herein. The system includes circuitry 10 for processing a signal and a plurality of antennas 12a-12b. A plurality of switches 22a-22b are also included. Each of the switches 22a-22b is coupled between the processing circuitry 10 and a corresponding one of the antennas 12a-12b. Each of the switches 22a-22b includes first and second power MOSFETs where the source of the first MOSFET is coupled to the source of the second MOSFET. The system further includes circuitry 28 for selecting of one of the plurality of switches 22a-22b to be on.

Abstract: A highly accurate UHF television tuner utilizes an improved housing and an improved mounting system for securing the tuning rotor and stator within the housing. The housing is fabricated from sheet metal that is welded at the corners to provide mechanical rigidity, and soldered at the corners to provide a good electrical contact. A cover is placed over an open end of the housing and soldered at the corners further to increase the mechanical rigidity of the housing. The depth of the housing is increased to reduce the effects of the housing on the tuner elements. An eyelet is mounted in one end of the housing for supporting the rotor shaft, and the stator is mounted by insulating posts that are inserted through sleeves integrally formed in the housing. An improved contact for more effectively grounding the rotor shaft to the housing is provided, and an improved detenting system is provided for the selector shaft to reduce the effects of inertial creep.