With Shielding Means Patents (Class 330/68)
  • Patent number: 9007125
    Abstract: In general, an RF power amplifier comprises a controller, a driver, a splitter, a final stage, and a combiner coupled together to function as the RF power amplifier. One or more of the above components are arranged on one or more motherboards, e.g., a printed circuit board (PCB). A heat sink defines a base of the RF power amplifier, and in some embodiments includes at least two grooves formed therein, wherein the electrical components of the splitter and electrical components of the controller fit within one or more of the grooves so that these components can substantially disposed within the heat sink. In some embodiments, a power rail is also provided, and is also disposed substantially within the heat sink. The power rail groove of the heat sink and the carrier of the final stage provide an EMI shield of the power rail.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: April 14, 2015
    Assignee: Empower RF Systems, Inc.
    Inventors: Paulo Correa, Donald M. Wike, Leonid Mogilevsky
  • Patent number: 8902004
    Abstract: A circuit includes an amplifier including a differential input stage including a first input terminal and a second input terminal. The circuit further includes a differential input line coupled to the first input terminal and the second input terminal, and shielding at least partially encompassing the differential input line. The shielding is connected to a node of the differential input stage of the amplifier.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: December 2, 2014
    Assignee: Xilinx, Inc.
    Inventors: Patrick J. Quinn, John K. Jennings, Darragh Walsh, Padraig Kelly
  • Patent number: 8390382
    Abstract: There is provided a power amplifier circuit capable of improving cross isolation between a high frequency band power coupler and a low frequency band power coupler, by directly transmitting power to the high frequency band power coupler and the low frequency band power coupler from a power amplifier, and forming a predetermined inductance circuit or an LC resonance circuit in a line transmitting the power to the high frequency band power coupler. The power amplifier circuit may include a power amplifying unit supplied with power from the outside and amplifying an input signal, a coupling unit having a high frequency band power coupler and a low frequency band power coupler, and an isolation unit including a first power line and a second power line, wherein the first power line has an inductor blocking signal interference generated in a predetermined frequency band.
    Type: Grant
    Filed: February 10, 2011
    Date of Patent: March 5, 2013
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Ki Joong Kim, Youn Suk Kim, Seong Geon Kim, Jun Goo Won, Joong Jin Nam
  • Publication number: 20120294201
    Abstract: There is provided an amplifier apparatus and a signal processing apparatus that reduce a delay or distortion of a power supply voltage used for drain modulation. An amplifier apparatus is an amplifier apparatus that performs drain modulation, and includes a printed circuit board having a first surface and a second surface; an amplifier circuit disposed on the first surface; and a modulation power supply circuit that supplies a variable power supply voltage for performing drain modulation, to the amplifier circuit. The modulation power supply circuit has an output portion that outputs the power supply voltage. The amplifier circuit has an input portion to which the power supply voltage is supplied. The output portion is located on the side of the second principal surface of the printed circuit board and is connected to the input portion through a conductor penetrating through the printed circuit board.
    Type: Application
    Filed: February 22, 2011
    Publication date: November 22, 2012
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yorinao Kurokawa, Tatsuhiro Shimura
  • Patent number: 8253486
    Abstract: There is provided a wireless apparatus having a shielding function for shielding signal interference between driving power from a power amplifier and a conductive wire of a coupler. The wireless apparatus having a shielding function, includes an amplifying unit receiving preset driving power and amplifying a radio frequency (RF) input signal according to a preset gain, an impedance matching unit including at least one coil, receiving the driving power from the amplifying unit, and matching the impedance of a path of a signal, amplified from the amplifying unit, through the coil, and a shielding unit eliminating signal interference between the coil and a transmission path of the driving power from the amplifying unit.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: August 28, 2012
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Ki Joong Kim, Tae Joon Park, Young Jean Song, Jun Goo Won, Youn Suk Kim
  • Patent number: 7760017
    Abstract: An amplifier structure includes shield conductors that are provided spatially adjacent to elongated feedback signal lines that couple a feedback circuit to an amplifier input. The shield conductors are provided between the feedback signal lines and a ground plane, which interrupts a parasitic capacitance that otherwise would be established between the feedback signal line and ground. The shield conductors are electrically coupled to the amplifier's outputs which create a capacitance between the output terminal and the feedback signal line. In some embodiments, the capacitance generated between the output terminal and the feedback signal line can suffice as a capacitor in a feedback path of the amplifier and be contained in an integrated circuit die on which the amplifier is manufactured. Optionally, a structure may be provided that eliminates common mode signals on the feedback lines while simultaneously preserving the common mode signals on the amplifier output terminals.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: July 20, 2010
    Assignee: Analog Devices, Inc.
    Inventors: Kimo Y. F. Tam, Stefano D'Aquino
  • Patent number: 7741915
    Abstract: Disclosed is a power amplification apparatus in a communication system. The apparatus includes a high power amplifier for amplifying an input signal; and a lattice panel, one surface of which is in contact with a ground plane of the high power amplifier, the one surface including a first line and a second line. The first line has at least two first etched portions and at least one first copperplate portion, the first copperplate portion being positioned between the first etched portions, and the first copperplate portion being formed at an interval of ? 0 4 , and the second line has at least two second etched portions and at least one second copperplate portion, the second copperplate portion being positioned between the second etched portions, and the second copperplate portion being formed at an interval of ? 0 ? 4 .
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: June 22, 2010
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Jin-Ho Yoon
  • Patent number: 7259625
    Abstract: The present invention provides a differentially driven monolithic inductor circuit having a shield differentially driven by phase shift buffers and a single-ended monolithic inductor circuit having single-ended shields driven by phase shift buffers, both inductor circuit types providing high Quality factor (Q) at operating frequencies in the multi-GHz range and circuits incorporating the same.
    Type: Grant
    Filed: April 5, 2005
    Date of Patent: August 21, 2007
    Assignee: International Business Machines Corporation
    Inventor: David I. Sanderson
  • Patent number: 7133705
    Abstract: A portable power amplifier includes portable encapsulating cases, a printed board incorporated in those encapsulating cases, and a power amplifying device mounted on this printed board. An antenna switch and an antenna are provided near the power amplifying device, which is connected to those components in a pattern. This structure improves heat dissipation efficiency of the portable power amplifier.
    Type: Grant
    Filed: May 23, 2002
    Date of Patent: November 7, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Terumoto Akatsuka, Keisuke Utsunomiya, Haruki Owaki, Motoyoshi Kitagawa
  • Patent number: 7068521
    Abstract: In a semiconductor device such as a high-frequency power amplifier module, a plurality of amplifying means are formed on a semiconductor chip which is mounted on a main surface of a wiring substrate, and electrodes of the semiconductor chip are electrically connected by wires to electrodes of the wiring substrate. In order to make the high-frequency power amplifier module small in size, a substrate-side bonding electrode electrically connected to a wire set at a fixed reference electric potential is place at a location farther from a side of the semiconductor chip than a substrate-side output electrode electrically connected to an output wire. A substrate-side input electrode electrically connected to an input wire is located at a distance from the side of the semiconductor chip about equal to the distance from the side of the semiconductor chip to the substrate-side output electrode, or at a location farther from the side of the semiconductor chip than the substrate-side bonding electrode is.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: June 27, 2006
    Assignees: Renesas Technology Corp., Hitachi Tohbu Semiconductor, Ltd.
    Inventors: Iwamichi Kohjiro, Yasuhiro Nunogawa, Sakae Kikuchi, Shizuo Kondo, Tetsuaki Adachi, Osamu Kagaya, Kenji Sekine, Eiichi Hase, Kiichi Yamashita
  • Patent number: 6624703
    Abstract: This invention provides a terminal arrangement for an electrical device. The electrical device includes a ground terminal on its outer surface that has a relatively large surface area. The electrical device also includes a plurality of contact terminals that are arranged around the periphery of the outer surface. Preferably, these terminals are generally equally-spaced from each other. Where the outer surface is rectangular, a terminal is normally located in each corner and one or more terminals are located along a side between the corners. The electrical device can be, for instance, a power amplifier. In such an arrangement, the amplifier is used to receive a radio frequency signal at a first side of the outer surface and output an amplified radio frequency signal from a second side of the outer surface. The power used to operate the amplifier is provided by power supply signals that typically enter at outer surface corners.
    Type: Grant
    Filed: October 2, 2000
    Date of Patent: September 23, 2003
    Assignee: Skyworks Solutions, Inc.
    Inventors: Shiaw Chang, Kevin Choi, Roger J. Forse
  • Patent number: 6624692
    Abstract: A radio frequency amplifier includes a waveguide filter positioned between a first and a second amplifier circuit, which reduces the distortion between the amplifier circuits. The waveguide includes a main body having a cavity.
    Type: Grant
    Filed: April 17, 2001
    Date of Patent: September 23, 2003
    Assignee: Alps Electric Co., Ltd.
    Inventors: Shigetaka Suzuki, Akira Takayama
  • Patent number: 6611170
    Abstract: An angular rate amplifier, which is adapted to amplify useful signals, which are proportional to rotation motion of a carrier, and to suppress noise, which is not proportional to rotation motion of a carrier, in output signals from an angular rate producer, including a MEMS (MicroElectronicMechanicalSystem) angular rate sensor. Compared with a conventional amplifiers, a noise shield and a co-resident trans impedance amplifier are utilized to achieve high signal/noise ratio. Furthermore, the angular rate producer and the noise shield and a co-resident trans impedance amplifier are used in a micro inertial measurement unit (IMU) to improve performance of the micro inertial measurement unit to form highly accurate, digital angular increments, velocity increments, position, velocity, attitude, and heading measurements of a carrier under dynamic environments.
    Type: Grant
    Filed: February 13, 2001
    Date of Patent: August 26, 2003
    Assignee: American GNC Corporation
    Inventors: Hiram McCall, Ching-Fang Lin
  • Publication number: 20030117220
    Abstract: An object of the present invention is to provide a radio frequency power amplifier of multi stage amplifying method that is designed to reduce instability of output power caused by electromagnetic coupling of bias supply terminals and interconnections of each stage to thereby operate stably. Another object of the present invention is to provide a radio frequency power amplifier that is designed to reduce distortion of output power caused by electromagnetic coupling of bias supply terminals and interconnections of each stage to thereby provide high efficiency.
    Type: Application
    Filed: December 10, 2002
    Publication date: June 26, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Akira Kuriyama, Masami Ohnishi
  • Patent number: 6473314
    Abstract: A low cost radio frequency interference filter assembly comprises a multiple layer structure including a middle trace layer disposed between an upper ground layer and lower ground layer. Non-conductive insulation layers are disposed between the middle trace layer and the upper and lower ground layers. The upper layer includes input contacts, signal contacts, and capacitors which are coupled to the signal contacts and an upper grounded substrate. The middle trace layer includes a grounded substrate and trace lines which are coupled to the signal contacts of the upper layer by signal vias. The lower layer includes a grounded substrate. Ground vias are formed through the insulation layers to couple the middle grounded substrate to the upper and lower grounded substrates. The filter assembly may be formed as an integral projection of a printed circuit board assembly.
    Type: Grant
    Filed: August 3, 2000
    Date of Patent: October 29, 2002
    Assignee: Powerwave Technologies, Inc.
    Inventors: James Keith Custer, Pauline Mei-Seung Tong
  • Publication number: 20020135420
    Abstract: An angular rate amplifier, which is adapted to amplify useful signals, which are proportional to rotation motion of a carrier, and to suppress noise, which is not proportional to rotation motion of a carrier, in output signals from an angular rate producer, including a MEMS (MicroElectronicMechanicalSystem) angular rate sensor. Compared with a conventional amplifiers, a noise shield and a co-resident trans impedance amplifier are utilized to achieve high signal/noise ratio. Furthermore, the angular rate producer and the noise shield and a co-resident trans impedance amplifier are used in a micro inertial measurement unit (IMU) to improve performance of the micro inertial measurement unit to form highly accurate, digital angular increments, velocity increments, position, velocity, attitude, and heading measurements of a carrier under dynamic environments.
    Type: Application
    Filed: February 13, 2001
    Publication date: September 26, 2002
    Inventors: Hiram McCall, Ching-Fang Lin
  • Patent number: 6160453
    Abstract: A high-frequency power amplifier has a high-frequency input, a high-frequency output and at least one power transistor connected therebetween. The power transistor has a first electrode serving as a control input, a cooling terminal connected to a second electrode and a third electrode. The third electrode is connected to a high-frequency reference potential conductor and the high-frequency reference potential conductor is connected in terms of high-frequency to the second electrode. An input signal applied to the high-frequency input is coupled out as an output signal at the high-frequency output.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: December 12, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventors: Peter Feld, Horst Kroeckel, Markus Vester
  • Patent number: 6144260
    Abstract: The present invention relates to an amplifier comprising a first amplification circuit (1) formed of a first transistor (10) and a second amplification circuit (2) formed of a second transistor (11), wherein a first filter (3) having a desired pass-band and a desired attenuation band is connected between the output section of the foregoing first amplification circuit (1) and the input section of the foregoing second amplification circuit (2), thereby reducing noises in the output.
    Type: Grant
    Filed: March 2, 1998
    Date of Patent: November 7, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Koji Hashimoto, Yoshikuni Fujihashi, Hiroshi Takahashi, Kazuhiro Yahata
  • Patent number: 6133787
    Abstract: A method and apparatus for controlling the common mode impedance misbalance of an isolated single-ended circuit for all common mode paths, thereby allowing the balancing of the common mode impedances which reduces common mode effects while maintaining the advantages of the single-ended amplifier including circuit simplicity and the reference input connected to circuit ground. In one embodiment, two solid shields enclose the circuit as completely as possible with the inner shield connected to circuit ground which is also the reference for all other inputs to the circuit. A discrete capacitor is connected between the outer shield and each of the non-reference inputs. When the shield is complete, i.e., solid, almost solid with minimal holes or a fine mesh, the value of the discrete capacitor is selected to match the parasitic capacitance formed between the outer shield and the inner shield. In another embodiment, the shield may be incomplete, i.e.
    Type: Grant
    Filed: May 6, 1999
    Date of Patent: October 17, 2000
    Assignee: Physio-Control Manufacturing Corporation
    Inventors: Daniel Yerkovich, Douglas K. Medema, Randall J. Makela
  • Patent number: 6118672
    Abstract: The tuner structure of the present invention includes: a circuit board on which electronic circuit components such as transistors and resistors have been mounted; a chassis angle; and a shield cover. In the tuner structure, a feedthrough capacitor for inputting/outputting a power, a control signal and the like is mounted to a metal plate disposed in parallel to the circuit board.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: September 12, 2000
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Miyoshi Yamauchi, Mitsuhiro Noboru, Haruo Koizumi, Syuuji Matsuura, Toshifumi Akiyama
  • Patent number: 6040739
    Abstract: A new amplifier module construction enhances the manufacturer's ability to repetitively construct multiple copies of millimeter microwave amplifiers having performance characteristics that are consistent with one another, particularly in input VSWR ratio characteristic, and which performance characteristic do not significantly change following any necessary rework of the amplifier module, including any MMIC chip replacement. In this module, a waveguide to microstrip transition is formed of a backshort member that is separate from the metal base or cover and that backshort member is held pressed in place against the substrate by force exerted by the module's cover plate through a spring member against the exterior of the backshort member. The spring member is formed by a resilient compressible gasket.
    Type: Grant
    Filed: September 2, 1998
    Date of Patent: March 21, 2000
    Assignee: TRW Inc.
    Inventors: Robert S. Wedeen, Arthur J. Durham, Matthew D. Ferris, G. Sam Dow
  • Patent number: 6040741
    Abstract: A preamplifier for amplifying signal voltages from a signal source with high source impedance has a signal input connected to the signal source, a first supply voltage terminal connected to the first power supply voltage potential, a second supply voltage terminal connected to a second power supply voltage potential and a signal output supplying an output signal. In this preamplifier, the first and second power supply voltage potentials can be shifted in parallel depending on the output signal. Alternatively or cumulatively, a known preamplifier may be developed so that the potential of a shield for the signal source can be controlled by the output signal.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: March 21, 2000
    Assignee: Krohne Messtechnik GmbH & Co. KG
    Inventor: Roland Van der Pol
  • Patent number: 6011700
    Abstract: A shielding case eliminates the problem in that the fixing portion of a feed-through capacitor juts out of the cabinet thereof; it does not affect the mounting conditions or the like of internal electronic components even if a part of the cabinet is bent inward to provide a portion on which the feed-through capacitor is mounted; and it enables automated assembly. The shielding case provides all the aforesaid advantages without sacrificing the shielding effect thereof.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: January 4, 2000
    Assignee: Alps Electric Co., Ltd.
    Inventor: Satoru Matsuzaki
  • Patent number: 5990736
    Abstract: A high frequency power amplifier including: a multi-layer printed-circuit board, a transistor for amplifying an input signal and outputting the amplified signal, a first print circuit pattern for receiving the input signal and supplying the input signal to the transistor, a second print circuit pattern for supplying a supply voltage to the transistor, a ground terminal, and concentrated constant elements connected to the transistor on the multi-layer printed-circuit board is disclosed, wherein at least two layers of the multi-layer printed-circuit board are connected to the ground terminal, the first and second print circuit patterns are sandwiched on one layer of the multi-layer print circuit between the at least two layers, a first shielding circuit pattern, connected to the ground terminal, arranged around the first print circuit pattern on the one layer is further provided; and a second shielding circuit pattern, connected to the ground terminal, arranged around the second print circuit pattern on the one
    Type: Grant
    Filed: May 6, 1998
    Date of Patent: November 23, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Isao Nasuno, Yohei Ichikawa
  • Patent number: 5831476
    Abstract: A method (140) for tuning millimeter-wave FET amplifiers (20) during manufacture, through the application (144) of a gate bias voltage (52) so as to tune the FET (22) of the amplifier (20) to match an input circuit (24), and through the application (146) of a drain bias voltage (74) so as to tune the FET (22) of the amplifier (20) to match an output circuit (26), then measuring (150) the frequency response of the amplifier (20). This tuning method (140) is repeated (152) until a predetermined frequency response has been achieved. Once achieved, the predetermined frequency response is realized (154) by permanently fixing the gate bias voltage (52) and the drain bias voltage (74) at the determined values. This iterative method (140) of tuning amplifiers (20) is then repeated for all amplifiers (20) to be tuned.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: November 3, 1998
    Assignee: Motorola, Inc.
    Inventors: Kenneth Vern Buer, John Holmes, David Warren Corman
  • Patent number: 5814761
    Abstract: A passive Electromagnetic Interference (EMI) dissipation apparatus typically utilized with an active host component to reduce self-generated and externally-generated electromagnetic interference and to improve the performance of the host component is disclosed. The apparatus includes a housing and a circuit located within the housing. The circuit includes a plurality of pyramidal-shaped resonating chambers having internally conductive surfaces covered with a layer of electrically resistive material, a plurality of quartz resonators each mounted upon a damping compound, and a plurality of permanent magnets each including a magnetically permeable bar. The electromagnetic interference is dissipated in the circuit over a broad range of frequencies in the form of heat. In a preferred embodiment, the plurality of permanent magnets and the corresponding plurality of permeable bars are mounted within a common chamber located immediately below the base of each of the pyramidal-shaped resonating chambers.
    Type: Grant
    Filed: September 7, 1995
    Date of Patent: September 29, 1998
    Assignee: Shakti Audio Innovations
    Inventor: Benjamin J. Piazza
  • Patent number: 5412340
    Abstract: The present invention provides a shield structure for shielding a microwave circuit device, which can establish a reliable electric contact between the ground wiring patterns of a circuit substrate, and can completely prevent external noise from entering into the circuit, with the use of a light and compact shield case. A circuit substrate has microwave components mounted thereon, ground patterns formed on peripheral portions of the upper surface of the substrate, and a ground pattern formed in the lower surface of the substrate along the entire periphery thereof. A shield case main body receiving the circuit substrate comprises a case main body, a top plate, and a bottom plate. The thickness of the case main body increases from a predetermined position such that it contacts the ground patterns. The bottom plate is coupled integral with the case main body with the circuit substrate interposed therebetween, in a state where the circuit substrate is received in the body.
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: May 2, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Sadao Tanikoshi
  • Patent number: 5352991
    Abstract: A power amplifier assembly that dissipates a maximum of one thousand one hundred watts includes a power amplifier circuit and a chassis that has an overall volume of 0.02 cubic meters. The chassis includes a heat sink base that contains a mounting pattern for the power amplifier circuit. By thermally coupling the power amplifier circuit to the heat sink base via thermal coupling devices and the mounting pattern, the heat sink base dissipates a maximum of one thousand one hundred watts in a volume of 0.016 cubic meters.
    Type: Grant
    Filed: August 12, 1993
    Date of Patent: October 4, 1994
    Assignee: Motorola, Inc.
    Inventors: Jeffrey S. Lipschultz, John N. Lubbe, Marc H. Pullman
  • Patent number: 5274340
    Abstract: In a microwave multistage amplifier, a shield casing (8) has a partition plate (7) integrally moulded with and disposed in the casing (8); microwave amplifiers (5, 6) are arranged on a dielectric substrate so as to locate the partition plate therebetween; and an upper cover plate (11) is provided which can be screwed to partition plate (7). By virtue of the above-mentioned arrangement, it becomes possible to strictly separate rooms defined in the casing from each other and suppress generation of a surface wave mode of the microwave propagation on the dielectric substrate, thereby assuring an isolation between the amplifiers.
    Type: Grant
    Filed: April 13, 1992
    Date of Patent: December 28, 1993
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akihito Deki, Yukiro Kashima, Hirotaka Fujisaki
  • Patent number: 5087888
    Abstract: A way of constructing modular RF power amplifiers. RF power amplifiers are constructed of a standardized chassis plus a number of RF power modules with each such power module containing provisions for self-cooling.
    Type: Grant
    Filed: July 26, 1990
    Date of Patent: February 11, 1992
    Assignee: Motorola, Inc.
    Inventors: Michael C. Mountz, Peter A. Kwitkowski
  • Patent number: 5072193
    Abstract: The ease of manufacture and performance of printed circuit board RF amplifier and other electronic apparatus requiring a high degree of internal shielding is improved by distributing DC or other signals through rigid conduits having at least one flat side and containing the desired power or signal wires. The rigid conduit is typically soldered, flat side down, at multiple locations to an AC ground plane. The wires exit the conduit through side exit holes and end holes. Side holes are desirably provided at regular intervals. The flat side prevents or reduces rolling or other misalignment of the conduit during assembly, thereby easing circuit board construction. Conduits with square cross-sections are preferred.
    Type: Grant
    Filed: October 1, 1990
    Date of Patent: December 10, 1991
    Assignee: Motorola, Inc.
    Inventors: Lance G. Wilson, William J. Miller
  • Patent number: 4963833
    Abstract: An improved high powered power amplifier, where the improvement comprises an improved grounding technique by decreasing the contact resistance, and an improved thermal transfer and dissipating technique. The heat generated by a power amplifier device is transferred and dissipated substantialy outside a chassis and is in direct contact with a heat sinking device located outside the chassis. By having the heat transfer and heat dissipation occurring outside the chassis and by having the power amplifier device in direct contact with the heat sinking device, the power amplifier is capable of reliably operating at higher power levels.
    Type: Grant
    Filed: June 12, 1989
    Date of Patent: October 16, 1990
    Assignee: Motorola, Inc.
    Inventor: Michael C. Mountz
  • Patent number: 4751471
    Abstract: An amplifying circuit for amplifying a bipotential input signal, including an insulating housing having a conductive input contact mounted on the housing and adapted to engage a human body so that the bipotential input signal applied to the contact; a lead amplifier having inverting and non-inverting inputs, one of which is coupled to the input contact, and an output; first and second diodes connected in parallel inverse polarity across the inputs of the lead amplifier; third and fourth diodes connected in parallel inverse polarity from the inverting input of the lead amplifier to a circuit common potential; and an output resistor connected from the inverting input to the output of the lead amplifier. Portions of the input contact are surrounded by a voltage drive shield connected to the output of the lead amplifier.
    Type: Grant
    Filed: December 23, 1986
    Date of Patent: June 14, 1988
    Assignee: Spring Creek Institute, Inc.
    Inventor: W. J. Ross Dunseath, Jr.
  • Patent number: 4695678
    Abstract: An electronic device carrier structure includes at least one signal line which is connected to an electronic device, such as a one-chip operational amplifier, and at least a pair of guard lines extending substantially along the corresponding signal line each at one side thereof thereby preventing an electrical signal carried on the signal line from being adversely affected. Such a structure is preferably applied to a one-to-one image sensor including a single array of photoelectric elements and operational amplifier chips for amplifying signals supplied from the photoelectric elements through signal lines connected therebetween.
    Type: Grant
    Filed: October 5, 1984
    Date of Patent: September 22, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Masanori Itagaki, Junichi Takahashi, Hideyasu Endou
  • Patent number: 4679002
    Abstract: A low noise, high gain differential amplifier suitable for EEG amplification is constructed in a shielded metal enclosure, preferably on a ground plane circuit board. The amplifier is battery powered to eliminate all possibility of noise from the power system. The amplifier utilizes a pair of operational amplifiers to provide high input impedance for each of two input signals. A differential amplifier generates an internal signal which is filtered and amplified by a pair of bandpass amplifiers and overlapping low pass and high pass amplifiers.
    Type: Grant
    Filed: April 25, 1985
    Date of Patent: July 7, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Gary W. Sherwin, John M. Zomp
  • Patent number: 4625178
    Abstract: A feedforward amplifier arranged as a unitized gain block particularly suitable for use in cable communication systems. The feedforward amplifier includes a single circuit board integrally mounting the directional couplers, delay lines and attenuator circuitry in a symmetrical arrangement. The main and error amplifiers are mounted separately from the main circuit board via releasable connectors and each amplifier is arranged on its substrate as a mirror image of the other to provide a symmetrical signal path. The amplifiers and the circuit board are enclosed within a compact metal housing which provides heat sinking for the amplifiers and facilitates removal of the amplifiers for servicing.
    Type: Grant
    Filed: July 19, 1985
    Date of Patent: November 25, 1986
    Assignee: General Instrument Corporation
    Inventor: Leif R. Mannerstrom
  • Patent number: 4585999
    Abstract: A low noise radiofrequency amplifier (10), using a dc SQUID (superconducting quantum interference device) as the input amplifying element. The dc SQUID (11) and an input coil (12) are maintained at superconductivity temperatures in a superconducting shield (13), with the input coil (12) inductively coupled to the superconducting ring (17) of the dc SQUID (11). A radiofrequency signal from outside the shield (13) is applied to the input coil (12), and an amplified radiofrequency signal is developed across the dc SQUID ring (17) and transmitted to exteriorly of the shield (13). A power gain of 19.5.+-.0.5 dB has been achieved with a noise temperature of 1.0.+-.0.4 K. at a frequency of 100 MHz.
    Type: Grant
    Filed: April 27, 1984
    Date of Patent: April 29, 1986
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Claude Hilbert, John M. Martinis, John Clarke
  • Patent number: 4412183
    Abstract: An AC resistor attenuator with low parasitic capacitance coupling and, thus, a substantially constant attenuation value over a relatively wide frequency range is disclosed. The AC resistor attenuator comprises a first elongate resistor substantially entirely surrounded by a second elongate resistor. The first and second elongate resistors are thermally matched and have a substantially identical resistance profile. The first and second resistors are connected in series. The other ends of the first and second resistors are connected across the source of the signal to be attenuated. The attenuated signal is obtained at the junction between the first and second resistors. Except in the case where fifty percent (50%) attenuation is to be provided, the higher value resistance of the attenuator forms the first resistor and the lower value forms the second resistor.
    Type: Grant
    Filed: October 6, 1980
    Date of Patent: October 25, 1983
    Inventor: Benjamin T. Brodie
  • Patent number: 4051444
    Abstract: A magnetic flowmeter system having a high impedance double ended AC preamplifier stage for amplifying voltages induced in a fluid flowing in and transverse to the field of an AC energized electromagnet. The preamplifier output voltages are amplified in a single-ended AC amplifier. The output voltage of the AC amplifier is demodulated by a phase sensitive detector. The DC output voltage is divided by a DC voltage derived from the AC source of energization for the electromagnet, so a net output voltage results which is free of common mode and quadrature voltages and independent of field fluctuations, but is obtained without feedback to the input of the system.
    Type: Grant
    Filed: June 7, 1976
    Date of Patent: September 27, 1977
    Assignee: Sybron Corporation
    Inventor: Heinz Walter Gruner