Rc Or Rl Type Patents (Class 333/172)
  • Patent number: 7064624
    Abstract: An isolator, such as a common-mode-reactor, and power-conditioner network is utilized to provide at least one of adequate segment impedance, cross-talk or adequate high-frequency-interference attenuation on, or between, participating segments. The participating segments comprise adequate power conditioning, and are supplied by an isolated or non-isolated common power supply. At least one of the segments may have one of two poles in resistive and/or capacitive and/or inductive contact to ground, as well as having one of the segments, in resistive and/or capacitive and/or inductive contact to another of one of two poles of other segments.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: June 20, 2006
    Assignee: Pepperl+Fuchs, Inc.
    Inventors: Denis M. Poirier, Steffen Graber
  • Patent number: 7057452
    Abstract: A circuit for correcting the offset of an amplification and filtering chain having a predetermined gain and cut-off frequency depending on the value of at least one capacitor, comprising: a correction means for subtracting from the chain input a correction signal depending on the value of a programmable digital word; a digital automaton for, in a setting phase, searching, then memorizing one of two consecutive values of the digital word between which the output signal of the chain switches sign, the input signal being canceled during a setting phase; and comprising a means for, during the setting phase, reducing the value of said at least one capacitor with respect to its normal operating value.
    Type: Grant
    Filed: January 26, 2004
    Date of Patent: June 6, 2006
    Assignee: STMicroelectronics S.A.
    Inventors: Jean Ravatin, François Van Zanten
  • Patent number: 7030717
    Abstract: An impedance matching wave filter includes an original wave filter and a match circuit. The match circuit is connected in parallel with the original wave filter and is able to be varied to produce impedance matching with the original wave filter in order to improve the condition of the return loss and to lower signal fading and signal distortion.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: April 18, 2006
    Assignee: Soontai Tech Co., Ltd
    Inventor: Shun-Ho Chung
  • Patent number: 7015774
    Abstract: A noise filter of the present invention includes an inductor and a resistor connected in parallel with each other. A power supply frequency current does not pass the resistor but passes through the inductor with no loss. On the other hand, a high frequency noise current including a resonance frequency current, does not pass the inductor but is dissipated at the resistor. Therefore, the noise filter does not charge noise power and so does not suffer from a problem due to power discharging. The resonance frequency current caused by the noise filter and the earth capacitance is also dissipated at the resistor. Therefore, no problem is caused by the resonance frequency current.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: March 21, 2006
    Assignee: EMC Inc.
    Inventors: Takashige Terakawa, Hideyuki Yamanaka
  • Patent number: 7002417
    Abstract: Disclosed is apparatus for operating with an RC filter (26, 26A), and a corresponding method. The apparatus includes circuitry (32) for use in measuring an actual value of at least one filter component and a controller (34), coupled to the measurement circuitry, for determining at least one adaptive filter (36, 46) coefficient using the measured actual value to so as to compensate for a deviation of at least one filter component value from an ideal value. Where the filter is embodied as an RC network, the circuitry measures an actual value of both a resistor and a capacitor, and the controller uses the measured actual value of the capacitor when determining the value of a resistor.
    Type: Grant
    Filed: March 21, 2003
    Date of Patent: February 21, 2006
    Assignee: Nokia Corporation
    Inventors: Jaako Maunuksela, Jussi Vepsäläinen, Tuomas Honkanen
  • Patent number: 7002435
    Abstract: There is disclosed a variable capacitance circuit which comprises: first to Nth variable capacitance elements C1-CN (N is an odd number) sequentially connected in series between an input terminal I and an output terminal O, whose capacitances change depending on voltage applied thereto; an ith bias line on the input terminal side provided between an input terminal portion of the first variable capacitance element and a connection point between a 2ith variable capacitance element and a (2i+1)th variable capacitance element; and an ith bias line on the output terminal side provided between an output terminal portion of the Nth variable capacitance element and a connection point between a (2i?1)th variable capacitance element and the 2ith variable capacitance element, where N and i are integers satisfying N=2n+1, n?1, 1?i?n.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: February 21, 2006
    Assignee: Kyocera Corporation
    Inventors: Tsuneo Mishima, Tetsuya Kishino, Hideharu Kurioka
  • Patent number: 6949988
    Abstract: A constant impedance filter maintains a constant input impedance for frequencies that are both inside the filter passband and outside the filter passband. The constant input impedance appears as a pure resistance. The constant impedance filter includes a plurality of filter poles that are connected in series. Each of the filter poles include an inductor, a capacitor, and a resistor. The value of the inductor, the capacitor, and the resistor are selected to provide a constant input impedance over frequency for each pole of the filter, which produces a constant input impedance for the entire filter over frequency. The constant impedance filter can be implemented as a low pass filter, a high pass filter, or a bandpass filter. Furthermore, the constant impedance filter can be implemented in a single-ended configuration or a differential configuration.
    Type: Grant
    Filed: July 14, 2003
    Date of Patent: September 27, 2005
    Assignee: Broadcom Corporation
    Inventor: Siavash Fallahi
  • Patent number: 6946934
    Abstract: The transmission line is provided with a signal strip, a resistive layer opposed to the signal strip across a dielectric layer, and a ground conductor electrically connected to the resistive layer, wherein, in the case where resistance per unit length occurring when a high frequency current induced in the resistive layer through capacitance formed by the dielectric layer between the signal strip and the resistive layer flows in the resistive layer and between the resistive layer and the ground conductor at the time of transmission of a high frequency signal of a predetermine frequency through the signal strip is defined as additional resistance and resistance per unit length occurring when the high frequency current flows through the ground conductor is defined as ground resistance, the additional resistance is larger than the ground resistance.
    Type: Grant
    Filed: December 17, 2003
    Date of Patent: September 20, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Hiroshi Kanno
  • Patent number: 6937115
    Abstract: An electrical component includes a capacitive impedance and a shunt path inductance cancellation feature provided by coupled windings. A filter having a capacitor with capacitor-path inductance cancellation provides enhanced performance over frequency compared with conventional capacitors.
    Type: Grant
    Filed: February 25, 2002
    Date of Patent: August 30, 2005
    Assignee: Massachusetts Institute of Technology
    Inventors: David J. Perreault, Joshua W. Phinney, Timothy C. Neugebauer
  • Patent number: 6867665
    Abstract: An integrated RF filter for use at microwave frequencies comprising: an integrated circuit inductor with connected integrated circuit capacitors, arranged as a tank circuit, and an integrated circuit shunt resistor; the inductor, capacitors and resistor being interconnected in a bridge-T filter arrangement.
    Type: Grant
    Filed: August 21, 2001
    Date of Patent: March 15, 2005
    Assignee: Sirific Wireless Corporation
    Inventors: Tajinder Manku, Bish Ray
  • Patent number: 6864761
    Abstract: A distributed capacitive/resistive electronic device. An electronic device is described which includes a dielectric substrate, a first resistive component, a second resistive component, and a connecting component. The first resistive component is affixed to a first side of the dielectric substrate. The second resistive component is affixed to a second side of the dielectric substrate, wherein the second side is oppositely located from the first side. The connecting component is affixed to the dielectric substrate, wherein the connecting component electrically connects the first resistive component to the second resistive component, wherein the connecting component is electrically connectable to other electronic circuitry, and wherein, at a location removed from the connecting component, the second resistive component is electrically connectable to other electronic circuitry.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: March 8, 2005
    Assignee: Agilent Technologies, Inc.
    Inventors: David D. Eskeldson, Martin L Guth
  • Publication number: 20040251988
    Abstract: The invention includes an integrated adjustable resistor. The integrated adjustable resistor includes a first electrode, a second electrode, and a phase change medium electrically connected to the first electrode and the second electrode. The integrated adjustable resistor further includes an adjustable pulse generator for applying a variable amount of energy to the phase change medium. A resistance of the phase change medium is continuously dependent upon the amount of energy applied to the phase change medium. A resistance dependent circuit is electrically connected to the first electrode and the second electrode. Operation of the resistance dependent circuit is continuously dependent upon the resistance of the phase change medium.
    Type: Application
    Filed: June 16, 2003
    Publication date: December 16, 2004
    Inventors: Manish Sharma, Heon Lee
  • Publication number: 20040212440
    Abstract: In a low-pass filter which is preferably used as a loop filter in a PLL or DLL, filter characteristics which are the same as those of a conventional low-pass filter are realized without causing collateral problems, such as an increase in the circuit area, the circuit complexity, or the resistance value, which may be caused due to size reduction of a capacitive element in the conventional low-pass filter. Thus, in a loop filter including a capacitive element and a resistive element which are connected in series, the first input terminal is provided at the side including the resistive element, and the second input terminal is provided at a connection point of the capacitive element and the resistive element. The first input terminal is supplied with the first electric current.
    Type: Application
    Filed: April 2, 2004
    Publication date: October 28, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Shiro Dosho
  • Patent number: 6809613
    Abstract: A transmission line filter having low reflectivity and Gaussian characteristics includes at least one inductive element aligned along the transmission line and at least one shunt configuration branching off the transmission line including a capacitive element and a resistive element. The transmission line filter is embodied in complete and incomplete Gaussian filters, and in both lumped element and distributed-element configurations. A method of designing a transmission line filter having low reflectivity and Gaussian characteristics is provided in which values for desired filter parameters are ascertained, formulas for the values of the inductive, capacitive and resistive elements are derived in terms of the desired filter parameters and the number of half-cells, a number of half-cells for the filter required to achieve the desired filter parameters is selected, and lumped element values for the inductive, capacitive, and resistive elements are estimated using the selected number of half-cells.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: October 26, 2004
    Assignee: Teradvance Communications, LLC
    Inventors: Antonije R. Djordjevic, Aleksandra Stekovic, Marcel F. C. Schemmann, Zoran Maricevic
  • Patent number: 6801103
    Abstract: A noise filter 10 of the present invention includes an inductor 71 and a resistor 11 connected in parallel with each other. A power supply frequency current bypasses the resistor 11 but passes through the inductor 71. A high frequency noise current including a resonance frequency current, on the other hand, bypasses the inductor 71 but is dissipated at the resistor 11. Therefore, the noise filter 10 does not accumulate noise power and so does not suffer from a problem due to power releasing. The resonance frequency current caused by combination of inductance of the inductance and earth capacitance in the noise filter 10 is also dissipated at the resistor 11, thus giving rise to no problem of its own.
    Type: Grant
    Filed: July 18, 2002
    Date of Patent: October 5, 2004
    Assignee: EMC Inc.
    Inventors: Takashige Terakawa, Hideyuki Yamanaka
  • Publication number: 20040183625
    Abstract: A control system for the characteristic parameters of an active filter includes: a system for the determination of the technological distribution of the components that provides the information related to said technological distribution of the components; an elaboration system for said information related to said technological distribution of the components; an active filter including at least two programmable passive circuital elements receiving said information related to said technological distribution of the components; said elaboration system, being aware of the topology for said active filter, comprises means for determining the value for said at least two programmable passive circuital elements; means for correcting the value for said at least two programmable passive circuital elements according to the value of the information related to said technological distribution of the components; means for determining the programming values for said at least two programmable passive circuital elements.
    Type: Application
    Filed: February 26, 2004
    Publication date: September 23, 2004
    Applicant: STMicroelectronics S.r.I
    Inventors: Andrea Baschirotto, Piertro Liguori, Vittorio Colonna, Gabriele Gandolfi
  • Patent number: 6794956
    Abstract: A circuit substrate includes resistive films are disposed on the surfaces of lands included in a circuit pattern and these resistive films are used as resistances connected in series to a capacitor. Therefore, the resistances are connected in series without increasing the inductance in the capacitor, and accordingly, a circuit having a small impedance variation with respect to frequency can be obtained. Therefore, it is possible to obtain a power supply circuit and so forth having stable operation and fast response.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: September 21, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Masaaki Taniguchi, Hidekazu Kitamura
  • Patent number: 6791434
    Abstract: A flat group-delay low-pass filter includes a series element connected between an input terminal and an output terminal, and a shunt element with one end thereof grounded. Inductors define the series element, a parallel circuit including a capacitor and a series circuit including a resistor and a capacitor defines the shunt element. The flat group-delay low-pass filter thus eliminates the need for inserting a fixed attenuator to control the effect of reflections due to impedance mismatching between the filter and other components. The resulting flat group-delay low-pass filter and an optical signal receiver including the filter have very low manufacturing costs and component costs.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: September 14, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Tatsuya Tsujiguchi
  • Patent number: 6788168
    Abstract: A filter is formed as an integrated circuit by resistive and capacitive elements and includes, for connection to ground, at least two separate pads of a chip designed to be connected individually to at least two separate terminals of a package.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: September 7, 2004
    Assignee: STMicroelectronics S.A.
    Inventors: Fabrice Guitton, Choukri Karoui
  • Publication number: 20040169565
    Abstract: The invention relates to a tuning circuit for tuning a filter stage, which has an RC element (1) with an RC time constant (&tgr;), with the RC time constant (&tgr;) being the product of the resistance of a resistor (R1) in the RC element (1) and the capacitance of a capacitor (C1), which is connected in series with the resistor (R1), in the RC element (1), having a comparator (10) for comparison of the voltage which is produced at the potential node (4) between the resistor (R1) and the capacitor (C1), with a reference ground voltage; and having a controller (15) which varies the charge on the capacitor (C1) in the RC element (1) until the comparator (10) indicates that the voltage which is produced at the potential node (4) is equal to the reference ground voltage, with the controller (15) switching a capacitor array (26) as a function of the charge variation time, which capacitor array (26) is connected in parallel with the capacitor (C1) in the RC element (1), in order to compensate for any discrepancy bet
    Type: Application
    Filed: February 6, 2004
    Publication date: September 2, 2004
    Inventors: Richard Gaggl, Manfred Nopp, Peter Pessl, Christian Schranz, Dietmar Straussnigg
  • Patent number: 6784760
    Abstract: A filter circuit directed primarily to use in the CATV industry includes at least one frequency dependent component, such as an RF choke, capacitor or inductor, for attenuating signals over at least a portion of the frequency range of signals which pass through the filter. In a typical application, signals are transmitted and received in both forward and return paths at each end of a multi-channel, two-way communication system. Signals in the frequency range of the return path, or of both paths, are attenuated by a desired amount, which is essentially constant over the frequency range of attenuation. In any case, the circuit component providing the attenuation is frequency dependent, thus providing a number of advantages, such as reducing the number of circuit components, reducing filter size and cost, and/or increasing the filter's electric surge and power handling capabilities.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: August 31, 2004
    Assignee: John Mezzalingua Associates, Inc.
    Inventors: Ahmet Burak Olcen, Henry Pixley
  • Publication number: 20040164819
    Abstract: There is disclosed a variable capacitance circuit which comprises: first to Nth variable capacitance elements C1-CN (N is an odd number) sequentially connected in series between an input terminal I and an output terminal O, whose capacitances change depending on voltage applied thereto; an ith bias line on the input terminal side provided between an input terminal portion of the first variable capacitance element and a connection point between a 2ith variable capacitance element and a (2i+1)th variable capacitance element; and an ith bias line on the output terminal side provided between an output terminal portion of the Nth variable capacitance element and a connection point between a (2i−1)th variable capacitance element and the 2ith variable capacitance element, where N and i are integers satisfying N=2n+1, n≧1, 1≦i≦n.
    Type: Application
    Filed: September 25, 2003
    Publication date: August 26, 2004
    Applicant: KYOCERA CORPORATION
    Inventors: Tsuneo Mishima, Tetsuya Kishino, Hideharu Kurioka
  • Patent number: 6781217
    Abstract: A transmission line structure comprises a plurality of conductive lines over an insulating layer. With three conductive lines, a center conductive line is disposed between the outer conductive lines to define a gap distance therebetween that is less than their height. In a further aspect, a conductive layer (e.g., a ground plane) contacts the insulating layer on a side thereof opposite the plurality of conductive lines. A ratio for the height of the conductive lines relative to the distance therebetween is kept greater than another ratio for the width of the center conductor relative to the thickness of the insulating layer.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: August 24, 2004
    Assignee: Intel Corporation
    Inventor: David GenLong Chow
  • Patent number: 6781482
    Abstract: An integrated circuit having a substrate and an LC tank circuit comprises an inductor with parallel capacitors. The capacitors include triple plate integrated capacitors having a highest metal plate, a common middle plate and a lowest metal plate. The lowest plate is connected to a virtual ground node. A control circuit element connected to the middle plate allows the resonant frequency of the tank circuit to be controlled.
    Type: Grant
    Filed: December 18, 2002
    Date of Patent: August 24, 2004
    Assignee: Zarlink Semiconductor Limited
    Inventor: Peter Graham Laws
  • Patent number: 6782055
    Abstract: A receiver circuit that can obtain a reception signal with accuracy in high-speed communications using two-wire transmission lines. The receiver circuit receives information signals in a communication system with two-wire transmission lines for transmitting the information signals in opposite phases to each other. The receiver circuit includes an alternating-current coupling arrangement provided for each of the two-wire transmission lines and for extracting alternating-current components of the information signals inputted through the transmission lines. The receiver circuit also includes a reception signal generating arrangement for obtaining a reception signal corresponding to the information signals in accordance with output signals from each of the alternating-current coupling arrangements. Each of the alternating-current coupling arrangements include two time constant circuits having time constants different from each other and connected in parallel to each other between an input and output thereof.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: August 24, 2004
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Yuji Nagatani, Kazuya Iwamoto, Hiroshi Hashimoto
  • Patent number: 6774714
    Abstract: A functional circuit and a filter are disposed between a first power supply wire capable of being set in a first electric potential of a semiconductor device and a second power supply wire capable of being set in a second electric potential, which is different from the first electric potential. The functional circuit is connected to the first power supply wire or the second power supply wire. Then, the filter transmits a signal inputted or outputted between the outside of the semiconductor device and the functional circuit.
    Type: Grant
    Filed: October 12, 2001
    Date of Patent: August 10, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsuyoshi Chida, Yasuhiro Hegi
  • Patent number: 6759926
    Abstract: An LC filter circuit includes first and second LC-trap capacitor conductors, respectively, that are opposed to third and LC-trap capacitor conductors with an insulating sheet therebetween to define first and second LC trap capacitors, respctively. A portion of a first LC resonator inductor and the first LC trap capacitor define an input-side LC trap circuit, and a portion of a second LC resonator inductor and the second LC trap capacitor define an output-side LC trap circuit.
    Type: Grant
    Filed: August 6, 2002
    Date of Patent: July 6, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Naoto Yamaguchi
  • Publication number: 20040095209
    Abstract: A first operational amplifier receives a reference voltage at one input terminal, a first transistor is connected between a first power source line and the first operational amplifier, a second transistor is connected between the first power source line and the first operational amplifier, a resistor is connected between the first transistor and a second power source line, a first switch is connected to the second transistor, a variable capacitor connected between the first switch and the second power source line, a second switch is connected the variable capacitor and the second power source line, a second operational amplifier is connected to the variable capacitor and the reference voltage, a third switch is connected to the second transistor, a load is connected between the third switch and the second power source line, and a control circuit is connected to the first to third switches.
    Type: Application
    Filed: April 24, 2003
    Publication date: May 20, 2004
    Inventor: Hiroyuki Mori
  • Patent number: 6737911
    Abstract: The adaptive filter can be realized with a very low circuitry outlay, as a result of which the adaptive filter for the first time becomes practical for many applications. In particular, the area required by the filter is small since the large time constants that are necessary for many applications can be realized in a simple manner by the control circuit. The adaptive filter is suitable in particular for “mixed signal ASICS”, in which the required preconditions for the control circuit are already present, so that the control circuit can be realized just by means of corresponding wiring.
    Type: Grant
    Filed: December 10, 2001
    Date of Patent: May 18, 2004
    Assignee: Infineon Technologies AG
    Inventor: Udo Ausserlechner
  • Patent number: 6734760
    Abstract: A lumped filter includes an input terminal, an output terminal, and a ground electrode disposed on a dielectric film on an alumina substrate. A first spiral inductor is connected between the input terminal and the ground electrode. A second spiral inductor is connected between the output terminal and the ground electrode. MIM capacitors are inserted between the input terminal and the first spiral inductor, and between the output terminal and the second spiral inductor. A third spiral inductor is inserted between the first and second spiral inductors. The spiral inductors have self-inductance, and capacitance between the spiral inductors and the electrodes adjacent thereto, by which the spiral inductors self-resonate and define as parallel LC resonators.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: May 11, 2004
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Tatsuya Tsujiguchi
  • Patent number: 6727780
    Abstract: A method for achieving a desired value of electrical impedance between conductors of an electrical power distribution structure by electrically coupling multiple bypass capacitors and corresponding electrical resistance elements in series between the conductors. The resistance elements may be annular resistors, and may provide the designer a greater degree of control of the system ESR. The annular resistors may comprise a first terminal, an annular resistor, and a second terminal. The second terminal may be located within the confines of the annular resistor. The annular resistors may be printed onto a conductive plane (e.g. a power plane or a ground plane), or may be a discrete component.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: April 27, 2004
    Assignee: Sun Microsystems, Inc.
    Inventors: Istvan Novak, Valerie St.Cyr, Michael C. Freda, Merle Tetreault
  • Publication number: 20040075510
    Abstract: A distributed capacitive/resistive electronic device. An electronic device is described which includes a dielectric substrate, a first resistive component, a second resistive component, and a connecting component. The first resistive component is affixed to a first side of the dielectric substrate. The second resistive component is affixed to a second side of the dielectric substrate, wherein the second side is oppositely located from the first side. The connecting component is affixed to the dielectric substrate, wherein the connecting component electrically connects the first resistive component to the second resistive component, wherein the connecting component is electrically connectable to other electronic circuitry, and wherein, at a location removed from the connecting component, the second resistive component is electrically connectable to other electronic circuitry.
    Type: Application
    Filed: October 22, 2002
    Publication date: April 22, 2004
    Inventors: David D. Eskeldson, Martin L. Guth
  • Patent number: 6721544
    Abstract: A duplexer structure for allowing an RF transmitter and an RF receiver to share a common antenna includes impedance matching circuitry to match the receiver input impedance to the antenna impedance during a receive operation and impedance transformation circuitry to transform the antenna impedance to a lower impedance at the receiver input terminals during a transmit operation. The impedance matching circuitry and the impedance transformation circuitry of the duplexer share one or more passive components, thus reducing the overall number of components required to implement the duplexer. This reduction in component count reduces the amount of chip area required to implement the duplexer and increases the ease with which the RF transceiver is integrated onto a semiconductor chip. In one embodiment, the duplexer uses a differential topology to provide common mode noise rejection and even harmonic distortion cancellation within a transceiver.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: April 13, 2004
    Assignee: Intel Corporation
    Inventor: Luiz M. Franca-Neto
  • Patent number: 6696885
    Abstract: An IQ generator is integrated into an IC for generating IQ output signal. The IQ generator includes a signal generator providing input with two identical signals opposed in phase, a filter comprises a plurality capacitances and inductances, and output providing the I and Q signals. The capacitances and inductances of the filter are integrated into said integrated circuit.
    Type: Grant
    Filed: April 2, 2001
    Date of Patent: February 24, 2004
    Assignee: Nokia Mobile Phones Limited
    Inventor: Kaare Christensen
  • Patent number: 6690250
    Abstract: The invention relates to an RFI filter used for avoidance of mains retro-action in the form of radio noise. RFI filters are connected to frequency converters in order to reduce radio noise transmitted via conductors. These filters comprise large noise-decoupling capacitors which are connected to earth, and during start up of the frequency converter the capacitors cause leakage currents to earth. This gives rise to problems in those circumstances, where a circuit breaker is connected to a frequency converter and an RFI filter, because the leakage current is higher than the trigger current for the circuit breaker. The solution to this problem is to place a resistor in series with the noise-decoupling capacitor and parallel with the resistor to place a switch, which can be opened or closed with a control signal from a controller. The invention also concerns a method for activation of an RFI filter.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: February 10, 2004
    Assignee: Danfoss Drives A/S
    Inventor: Henry Møller
  • Patent number: 6674321
    Abstract: A capacitive element includes two or more voltage-variable capacitors (varactors). The varactors are configured so that they are coupled in series with respect to an applied AC signal and are coupled in parallel with respect to an applied DC bias voltage. The effective capacitance of the overall capacitive element can be tuned by varying the DC bias voltage.
    Type: Grant
    Filed: August 1, 2002
    Date of Patent: January 6, 2004
    Assignee: Agile Materials & Technologies, Inc.
    Inventor: Robert A. York
  • Patent number: 6674343
    Abstract: An electronic filter assembly of the type that includes a female terminal cap having a fitting portion and containing a terminal passage through the fitting portion, and a collet assembly secured in and substantially closing the terminal passage of the female terminal cap. The collet assembly comprises an insulator, a collet terminal, and a seal. The insulator is made from a single piece of insulator material, containing a bore therethrough. The collet terminal extends through the bore of the insulator. The seal is located inside the terminal passage of the female terminal cap, between the collet terminal and the female terminal cap.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: January 6, 2004
    Assignee: Tresness Irrevocable Patent Trust
    Inventors: Jerry M. Gould, Andrew F. Tresness
  • Patent number: 6661312
    Abstract: A multilayer filter array, which is formed by layering a plurality of conductive patterns, includes: coils corresponding to respective plurality of lines, which are formed by arranging the plurality of conductive patterns respectively to a single insulator layer; and capacitors corresponding to respective plurality of lines, which are formed by facing the conductive patterns to each other with insulator layers therebetween on insulator layers differing from the insulator layers the coils exist thereupon, wherein only a single conductive pattern, which configures a capacitor corresponding to a respective line, of the capacitors corresponding to respective plurality of lines, is deployed on each respective insulator layer forming each of the capacitors. Accordingly, inductance and capacitance become independently adjustable, as in addition, disparity of damping characteristics between signal lines may be made smaller.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: December 9, 2003
    Assignee: TDK Corporation
    Inventor: Masashi Orihara
  • Publication number: 20030222729
    Abstract: A method for tuning a filter to a desired frequency using successive approximation. Elements of the filter are selected according to a control code used to vary the filter's oscillation frequency. The control code is set to the middle of the control code range and resulting oscillation frequency is compared to the desired frequency. If the control code needs to be increased, the control code is set to ¾ of the control code range. If the control code needs to be decreased, the control code is set to ¼ of the control code range. The method continues using successive approximation to determine the value of each bit of the control code. Thus, successive approximation is used to converge on the value of the control code that produces an oscillation frequency of the filter that is closest to the desired frequency (with a maximum error of 1 least significant bit).
    Type: Application
    Filed: May 29, 2003
    Publication date: December 4, 2003
    Inventor: Lance M. Wong
  • Patent number: 6657522
    Abstract: A wide bandwidth bias tee including a high frequency terminal, a first resistor coupled between the high frequency terminal and a capacitor, a second resistor coupled to the capacitor, the second resistor coupled in series with the first resistor, and a low frequency terminal, the low frequency terminal coupled to the second resistor.
    Type: Grant
    Filed: February 1, 2002
    Date of Patent: December 2, 2003
    Assignee: M/A-Com
    Inventors: M. Tekamul Buber, Adil Khalil, Robert Ian Gresham
  • Patent number: 6657484
    Abstract: A system and method for decoupling capacitance for an integrated chip includes a load coupled between a power supply line and a ground. A distributed resistive-capacitive (RC) filter is coupled between the power supply line and the ground in series with the load. The distributed RC filter is operable to provide decoupled capacitance to the integrated circuit chip.
    Type: Grant
    Filed: May 30, 2002
    Date of Patent: December 2, 2003
    Assignee: Texas Instruments Incorporated
    Inventor: Patrick W. Bosshart
  • Patent number: 6617939
    Abstract: An equalization card is provided for a cable assembly carrying high speed data signals. The cable assembly includes a cable with conductors, a plug mounted on the cable and a socket receiving the plug. An equalization card is removeably received within the plug. The equalization card conveys data signals over data paths between the plug and receptacle. The circuit board attenuates frequency components below at least one half of the fundamental frequency of the data rate, without introducing equalization attenuation into frequency components below a second harmonic of the fundamental frequency. The circuit components maintains a substantially constant attenuation level for frequency components of the data signal below a predefined frequency cutoff that is less than the second harmonic of the fundamental frequency of the data rate.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: September 9, 2003
    Assignee: Tyco Electronics Corporation
    Inventor: Dean Vermeersch
  • Patent number: 6617941
    Abstract: A filter system includes at least two longitudinal branches with longitudinal inductors and at least one filter section (B) and an adjacent filter section (A). The filter section (B) is provided with at least one transverse branch that is interposed between the longitudinal branches, the adjacent filter section (A) adjoining the transverse branch. The number of inductors of a filter section that arc wound around different magnet cores can be reduced by equivalence transformation.
    Type: Grant
    Filed: January 2, 2002
    Date of Patent: September 9, 2003
    Assignee: Vacuumschmelze GmbH & Co. KG
    Inventor: Dirk Heumann
  • Publication number: 20030155994
    Abstract: A passive filter arrangement and a method of providing such a filter is described. The frequency response of the filter arrangement is substantially the same as the frequency response of a first filter of an order having a first value, the frequency response of the first filter being representable by a first set of one or more poles and/or one or more zeros. Descriptions of a plurality of second filters are generated, each second filter having an order lower than the order of the first value, each second filter having a frequency response representable by a one or more poles and/or one or more zeros, the one or more poles and/or one or more zeros of each lower order filter being a subset of the first set. The lower order filters are cascaded.
    Type: Application
    Filed: January 8, 2003
    Publication date: August 21, 2003
    Applicant: ALCATEL
    Inventors: Francois Jeanjean, Geert Arthur Edith Van Wonterghem
  • Patent number: 6608536
    Abstract: A constant impedance filter maintains a constant input impedance for frequencies that are both inside the filter passband and outside the filter passband. The constant input impedance appears as a pure resistance. The constant impedance filter includes a plurality of filter poles that are connected in series. Each of the filter poles include an inductor, a capacitor, and a resistor. The value of the inductor, the capacitor, and the resistor are selected to provide a constant input impedance over frequency for each pole of the filter, which produces a constant input impedance for the entire filter over frequency. The constant impedance filter can be implemented as a low pass filter, a high pass filter, or a bandpass filter. Furthermore, the constant impedance filter can be implemented in a single-ended configuration or a differential configuration.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: August 19, 2003
    Assignee: Broadcom Corporation
    Inventor: Siavash Fallahi
  • Publication number: 20030146809
    Abstract: A wide bandwidth bias tee including a high frequency terminal, a first resistor coupled between the high frequency terminal and a capacitor, a second resistor coupled to the capacitor, the second resistor coupled in series with the first resistor, and a low frequency terminal, the low frequency terminal coupled to the second resistor.
    Type: Application
    Filed: February 1, 2002
    Publication date: August 7, 2003
    Inventors: M. Tekamul Buber, Adil Khalil, Robert Ian Gresham
  • Patent number: 6590476
    Abstract: The present invention relates to a lowpass filter for effectively suppress a spurious in stop-band. The lowpass filter includes an input port microstrip element; an output port microstrip element; a first open-ended microstrip element; a second open-ended microstrip element; a first connector microstrip element; and, a second connector microstrip element. The each open-ended microstrips of the present invention is composed of distributed elements and distributed resistances connected each others in series and operated as a capacity, has a large impedance of the microstrip by low influence of a resistance in case of a low frequency, and has a small impedance of the microstrip by high influence of a resistance value in case of a high frequency. The present invention can effectively suppress the spurious characteristic, which is a disadvantage of the conventional lowpass filter composed of transmission lines at the RF band or the microwave band, by inserting resistance elements in open-ended microstrips.
    Type: Grant
    Filed: December 31, 2001
    Date of Patent: July 8, 2003
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Moon Que Lee, Keun Kwan Ryu, In Bok Yom, Seong-Pal Lee
  • Patent number: 6573811
    Abstract: A resistor tuning network for an RC filter has a first, fixed resistor and a second, variable resistance connected in parallel with the fixed resistor. The variable resistance is an R-2R ladder circuit having an input and first and second output terminals, with a first line having a plurality of first arms connected in series with the input and first output terminal and nodes between each pair of arms, each arm having an identical resistor R. A series of shunt arms are selectively connected between the respective nodes and the first or second output terminal. Each shunt arm has a 2R resistor and a switch in series, and each switch has a first, closed position connecting the shunt arm to the first output terminal and a second, open position connecting the shunt arm to the second output terminal, such that the resistance of the ladder network is varied dependent on the switch positions and is at a maximum value when all switches are closed and a minimum value when all switches are open.
    Type: Grant
    Filed: February 7, 2001
    Date of Patent: June 3, 2003
    Assignee: National Semiconductor Corporation
    Inventor: Brian C. Martin
  • Patent number: 6552629
    Abstract: In accordance with the teachings of this invention a novel method and apparatus is taught which provides for the stabilizing of an output signal through an output circuit having a compensation circuit coupled with an output capacitor, such that the compensation circuit is configured to compensate for an equivalent series resistance of the output capacitor. The compensation circuit compensates for the equivalent series resistance by providing a shift in a phase of the output signal to stabilize the output signal. The shift in phase is accomplished through the addition of a second zero at a second zero frequency to stabilize the output signal. The second zero is added such that the second zero frequency is closer to a first pole frequency than a first zero frequency, where the first pole frequency is proportional to the equivalent series resistance and the first zero is proportional to the output capacitor.
    Type: Grant
    Filed: December 12, 2000
    Date of Patent: April 22, 2003
    Assignee: Micrel, Incorporated
    Inventors: Jeffrey M. Dixon, Charles Coles, Andrew M. Cowell
  • Patent number: 6552630
    Abstract: A bi-directional low-pass filter for use at a user end or an office end in a communication network is disclosed. By providing compensation and high-band attenuation circuitry, the low-pass filter exhibits an improved attenuation value in high-band and a general attenuation value in a low-frequency band. The satisfactory attenuation performance in the high-frequency band minimizes the signal interference of a high-band communication terminal with a low-band communication terminal in the communication network. Further, by providing symmetric input/output circuitry, the low-pass filter can be operated reversibly.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: April 22, 2003
    Assignee: Primax Electronics Ltd.
    Inventors: Her-Jun Chueh, Kuang-Che Chen