Including Signal Feedback Means Patents (Class 330/291)
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Publication number: 20120293262Abstract: The invention relates to a configurable low noise amplifier circuit which is configurable between a first topology in which the low noise amplifier circuit includes a degeneration inductance whereby the low noise amplifier circuit operates as an inductively degenerated low noise amplifier, and a second topology in which the low noise amplifier circuit includes a feedback resistance whereby the low noise amplifier circuit operates as a resistive feedback low noise amplifier.Type: ApplicationFiled: May 19, 2011Publication date: November 22, 2012Inventors: Jari Johannes HEIKKINEN, Jonne Juhani Riekki, Jouni Kristian Kaukovuori
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Publication number: 20120293265Abstract: Embodiments of the invention are concerned with configurable RFICs. In an exemplary embodiment there is provided a configurable radio-frequency integrated circuit (RFIC) including one or more configurable low noise amplifier circuits, each of said one or more configurable low noise amplifier circuits being configurable between: an internal input impedance matching topology in which the respective low noise amplifier circuit includes one or more internal input impedance matching components adapted to match the input impedance of the respective low noise amplifier to a given input, said one or more internal input impedance matching components being located internally to the respective low noise amplifier circuit; and a topology different from said internal input impedance matching topology.Type: ApplicationFiled: October 12, 2011Publication date: November 22, 2012Inventors: Jari Johannes HEIKKINEN, Jonne Juhani RIEKKI, Jouni Kristian KAUKOVUORI
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Publication number: 20120286874Abstract: A Positive Feedback Common Gate Low Noise Amplifier (PFCGLNA) has positive feedback transistors and input transistors that are of the same conductivity type. Making the positive feedback and input transistors of the same conductivity type reduces sensitivity to process variations. Noise generated by the positive feedback transistors is used to cancel noise generated by the input transistors. In one embodiment, the PFCGLNA: 1) is tunable to have a substantially constant input impedance for any frequency in a wideband frequency range from 680 MHz to 980 MHz, and 2) has a noise figure less than 2.2 dB over the entire wideband frequency range. The input impedance of the PFCGLNA can be tuned to match a source that drives the PFCGLNA by setting a multi-bit digital control value supplied to a digitally-programmable tank load of the LNA.Type: ApplicationFiled: May 13, 2011Publication date: November 15, 2012Applicant: QUALCOMM INCORPORATEDInventors: Namsoo Kim, Joseph Patrick Burke
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Patent number: 8310311Abstract: According to an embodiment, a semiconductor integrated circuit device includes an amplifier and a feedback circuit. The amplifier includes an input terminal receiving an input signal and an output terminal outputting an output signal. The feedback circuit includes a first transistor generating a bias current. The feedback circuit is configured to operate based on the bias current. The feedback circuit is configured to receive the output signal to supply a feedback signal to the input terminal. A signal having a reverse phase to the output signal is input to a gate of the first transistor.Type: GrantFiled: September 21, 2010Date of Patent: November 13, 2012Assignee: Kabushiki Kaisha ToshibaInventor: Junji Wadatsumi
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Publication number: 20120268212Abstract: An amplifier arrangement comprising an amplifier (AMP) with a terminal (SPL) for a supply signal (VSPL) and a bias circuit (BIAS) for providing the supply signal (VSPL) at the terminal (SPL). The bias circuit holds an operating point (OP) of the amplifier (AMP) constant by means of the supply signal (VSPL). The bias circuit (BIAS) comprises a reference circuit (REF) for providing a reference signal (VREF) and a correction device (COR) by means of which the supply signal (VSPL) is regulated based on the reference signal (VREF) and a correction signal (Vfeed), the correction signal (Vfeed) being dependent on the operating point (OP) of the amplifier (AMP). A method for operating an amplifier arrangement is also described.Type: ApplicationFiled: March 23, 2012Publication date: October 25, 2012Applicant: austriamicrosystems AGInventor: Thomas CHRISTEN
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Publication number: 20120229216Abstract: A distributed amplifier with improved stabilization includes an input transmission circuit, an output transmission circuit, at least one cascode amplifier coupled between said input and output transmission circuits. Each cascode amplifier includes a common-gate configured transistor coupled to the output transmission circuit, and a common-source configured transistor coupled between the input transmission circuit and the common-gate configured transistor. The distributed amplifier also includes a non-parasitic resistance and capacitance coupled in series between a drain and a gate of at least one of the common-gate configured transistors for increasing the amplifier stability.Type: ApplicationFiled: March 6, 2012Publication date: September 13, 2012Inventor: Keith Benson
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Patent number: 8258873Abstract: An apparatus and method include a transmission line carrying a propagating signal between an inlet port and an outlet port. The propagating signal can include a forward traveling wave and optionally a backward traveling wave. A feedback stage samples a the propagating signal at the outlet port, generates a feedback signal the includes a time translation and a gain translation in the feedback energy, and routes the feedback signal to the inlet port such that the gain translation constructively interferes with the forward traveling wave and thereby increases the amplitude of the forward traveling wave.Type: GrantFiled: September 24, 2009Date of Patent: September 4, 2012Assignee: The Regents of the University of CaliforniaInventor: James Buckwalter
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Patent number: 8254598Abstract: An integrated circuit for providing programmable microphone interface includes an input terminal for receiving an input signal and an output terminal for providing an output audio signal. In an embodiment, the integrated circuit includes a bias circuit, an amplifier circuit and two feedback circuits. The amplifier circuit includes a first input, a second input, and an output. The first input receives either the input signal or a feedback signal, depending upon mode control signals. The second input receives either the feedback signal or the input signal depending upon the mode control signals. The first feedback circuit is in communication with the output and the first input of the amplifier and includes a first resistor and a first capacitor connected in parallel. The second feedback circuit includes an integrator circuit and provides the feedback signal. The mode control signals can be set in a programmable mode control register.Type: GrantFiled: June 12, 2007Date of Patent: August 28, 2012Assignee: Winbond Electronics CorporationInventor: Peter Holzmann
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Publication number: 20120200359Abstract: An amplifier arrangement with an amplifier arrangement input and an amplifier arrangement output is disclosed. The amplifier arrangement comprises a first transistor and a first ballast resistance, wherein the first ballast resistance connects a first transistor base of the first transistor to a common base terminal at least one second transistor and at least one second ballast resistance, wherein the at least one second ballast resistance connects a second transistor base of the at least second transistor to the common base terminal; and a feedback device comprising a feedback input terminal for sensing at least a base voltage of the first transistor and further comprising a feedback output terminal that is connected to the common base terminal.Type: ApplicationFiled: February 7, 2011Publication date: August 9, 2012Inventors: Udo Karthaus, Lothar Schmidt
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Patent number: 8228222Abstract: The disclosure relates to an amplifier comprising a digital delta-sigma modulator, a quantifier receiving a signal supplied by a delta-sigma stage and supplying a quantified signal, and a power circuit supplying an output signal. The device comprises N state loops of a first type configured to send the output signal to adders of N delta-sigma stages of lower rank, each state loop of the first type comprising an analog low-pass filter for supplying a filtered output signal, and an analog to digital converter for supplying a digital filtered output signal.Type: GrantFiled: December 15, 2010Date of Patent: July 24, 2012Assignees: Universite de Provence Aix-Marseillei, Centre National de la Recherche Scentifique, Primachip SASInventors: Hassan Ihs, Christian Dufaza
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Publication number: 20120176199Abstract: An integrated circuit according to one embodiment includes a first transimpedance amplifier and a second transimpedance amplifier. In the integrated circuit, one of the first transimpedance amplifier and the second transimpedance amplifier is set into an enabled state and the other is set into a disabled state. The first transimpedance amplifier and the second transimpedance amplifier share an input transistor. The first transimpedance amplifier has a first resistor provided between a feedback node thereof and an input node connected to the input transistor. The second transimpedance amplifier has a second resistor provided between a feedback node thereof and the first resistor. A feedback resistor of the second transimpedance amplifier is configured with a series connection of the first resistor and the second resistor.Type: ApplicationFiled: February 14, 2011Publication date: July 12, 2012Inventor: Daisuke Umeda
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Patent number: 8208876Abstract: A power amplifier controller circuit controls a power amplifier based upon an amplitude correction signal indicating the amplitude difference between the amplitude of the input signal and an attenuated amplitude of the output signal. The power amplifier controller circuit comprises an amplitude control loop and a phase control loop. The amplitude control loop adjusts the supply voltage to the power amplifier based upon the amplitude correction signal. The amplitude loop may include a variable gain amplifier adjusting the amplitude of the input signal. The amplitude loop can include a compression control block which may be configured either to adjust the gain in the variable gain amplifier or the voltage from the power supply based upon the operating level of the other, in addition to being based upon the amplitude correction signal, thus providing a way of maintaining the depth beyond the PA's compression point and allowing a control of the efficiency of the RF power amplifier.Type: GrantFiled: February 2, 2007Date of Patent: June 26, 2012Assignee: Quantance, Inc.Inventors: Serge F. Drogi, Vikas Vinayak
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Publication number: 20120154045Abstract: A push-pull low noise amplifier (LNA) includes at least one amplifier block. Each amplifier block includes a bypass stage and at least one gain cell. The bypass stage has a first node and a second node. The gain cell has an input terminal and an output terminal, comprising a loading stage and a driving stage. When the push-pull LNA is in a first gain mode, the loading stage is enabled and the bypassing stage is disabled; and when the push-pull LNA is in a second gain mode, the loading stage is disabled and the bypassing stage is enabled.Type: ApplicationFiled: May 17, 2011Publication date: June 21, 2012Inventors: Ming-Da Tsai, Yu-Hsin Lin
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Patent number: 8193720Abstract: An electrodeless lamp protecting device installed between an electrodeless lamp and a power source comprises a substrate having a feedback signal input module, a signal level determination module and a protection signal output module installed on the substrate. A signal of the power source is transmitted from the feedback signal input module to the signal level determination module, and the signal serves as a reference for an output signal of the protection signal output module, such that the electrodeless lamp has an automatic protection function upon the receipt of an abnormal signal.Type: GrantFiled: March 16, 2010Date of Patent: June 5, 2012Inventor: Chih-Chiang Yang
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Publication number: 20120105158Abstract: Provided is a feedback amplifier including: an amplification circuit unit to generate an output voltage by amplifying an input voltage inputted through an input terminal; an output circuit unit to output the generated output voltage through an output terminal; a feedback circuit unit to control the gain of the amplification circuit unit by determining a total feedback resistance value using an external control signal and controlling an input current while the total feedback resistance value is determined; and a bias circuit unit to apply a bias voltage to the feedback circuit unit.Type: ApplicationFiled: July 19, 2011Publication date: May 3, 2012Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTEInventors: Sang-Heung LEE, Hae Cheon Kim, Eun Soo Nam
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Patent number: 8154346Abstract: In one embodiment, a method includes: detecting one of a short-to-ground condition and a short-to-supply condition at an output node; selectively activating a feedback control transistor according to the detecting; detecting a first current passing through a first transistor using a second transistor sized to be smaller than the first transistor; mirroring the detected current using a plurality of transistors to form a feedback current; and providing the feedback current to a gate electrode of the first transistor according to the selectively activating the feedback control transistor.Type: GrantFiled: November 2, 2010Date of Patent: April 10, 2012Assignee: IML International LtdInventor: Chiayao S. Tung
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Patent number: 8149051Abstract: A solid-state image sensor capable of suppressing color mixture while suppressing increase of load capacitances of transfer gates and a short circuit between two adjacent transfer gates is provided. This solid-state image sensor comprises a plurality of transfer gates and a shielding material line blocking light incident from above a prescribed pixel upon another pixel adjacent to the prescribed pixel. The shielding material line has a downward projecting portion on a region corresponding to at least one transfer gate entering an ON-state in photoreception.Type: GrantFiled: January 27, 2006Date of Patent: April 3, 2012Assignee: Semiconductor Components Industries, LLCInventors: Yoshinari Ichihashi, Ryu Shimizu, Kazuhiro Sasada
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Publication number: 20120068771Abstract: An RF power amplifier device in which the circuit is provided on two separate dies which are attached together vertically. According to one embodiment of the present invention, the RF power amplifier includes a first die including an amplifying circuit for amplifying an RF signal, and a second die including at least one circuit component coupled to the amplifying circuit. The first die is vertically coupled to the second die, and the second die may be a flip chip and include harmonic loads and/or feedback circuit.Type: ApplicationFiled: September 22, 2010Publication date: March 22, 2012Inventors: James M. Carroll, John G. Heston, Jon Edward Mooney
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Patent number: 8115553Abstract: A radio frequency wide band amplifier having a noise that does not exceed a threshold value, and a linearity better than a threshold value. The radio frequency wide band amplifier architecture includes a first stage amplifier and a second stage amplifier. The second stage amplifier includes an input source resistor (Rin) that receives an input voltage signal, a feedback resistor (Rfb) directly connected to the input source resistor, a p-type metal-oxide-semiconductor (PMOS) transistor directly connected to the input source resistor. The PMOS transistor receives an output from the input source resistor. A n-type metal-oxide-semiconductor (NMOS) transistor directly connected to the input source resistor. The NMOS transistor receives an output from the input source resistor. A lumped output resistor (Rout) that receives an output from the feedback resistor, the PMOS transistor, and the NMOS transistor. A terminal of the lumped output impedance is connected to ground.Type: GrantFiled: September 15, 2010Date of Patent: February 14, 2012Assignee: Newport Media, Inc.Inventor: Dejun Wang
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Publication number: 20120025913Abstract: An envelope amplifier includes an amplifier unit, a comparator unit and an output unit. The amplifier unit is made up of a first output section that outputs a first current in response to an amplitude of an input envelope signal, and a second output section. The second output section outputs a second current of a current value proportionate to a current value of the first current. Absolute value of the current value of the second current is greater than that of a current value of the first current. Comparator unit compares the current value of the first current. The output unit sums a current via an inductor derived from a current sustained or broken in response to a compared result of the comparator unit to the second current to deliver the resulting sum current at an output end. The first current is configured to be terminated without being delivered to the output unit (FIG. 1).Type: ApplicationFiled: July 27, 2011Publication date: February 2, 2012Applicants: NEC CORPORATION, Renesas Electronics CorporationInventors: Yuri Honda, Yuji Takahashi
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Publication number: 20120025914Abstract: A CMOS power amplifier includes: a first MOS transistor connected between a first power terminal and a first output stage and having a gate connected to an input stage; a second MOS transistor connected between the first output stage and a ground and having a gate connected to the input stage; a switching circuit unit connecting or separating a feedback line between the input stage and the first output stage to select a linear amplifying operation or a non-linear amplifying operation; and a resistor formed at the feedback line between the input stage and the first output stage to determine a linear amplification gain when the feedback line is turned on.Type: ApplicationFiled: June 30, 2011Publication date: February 2, 2012Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.Inventors: Youn Suk KIM, Chul Hwan YOON, Joong Jin NAM, Ki Joong KIM, Jun Goo WON
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Patent number: 8107901Abstract: A feedback loop with an adjustable closed loop frequency response. The feedback loop contains adjustable pole (212, 213) and adjustable zero elements (220,221) for changing the pole and/or zero locations in the feedback loop's loop frequency response thereby changing the closed loop frequency response of the feedback loop. In one embodiment, the feedback loop is a Cartesian feedback loop suitable for use in a radio transmitter.Type: GrantFiled: August 20, 2001Date of Patent: January 31, 2012Assignee: Motorola Solutions, Inc.Inventors: Paul H. Gailus, Manuel P. Gabato, Kevin J. McCallum, Jeffrey B. Wilhite
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Publication number: 20120019325Abstract: A current-mode amplifier including an input stage, a feedback circuit and an output stage is provided. The input stage has an input terminal for receiving an input current of the current-mode amplifier. The input stage generates a corresponding inner current in accordance with the input current and a feedback current. The feedback circuit is connected to the input stage. The feedback circuit generates the corresponding feedback current in accordance with the inner current of the input stage. An input terminal of the output stage is connected to an output terminal of the input stage. An output terminal of the output stage serves as an output terminal of the current-mode amplifier.Type: ApplicationFiled: August 13, 2010Publication date: January 26, 2012Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTEInventors: Horng-Yuan Shih, Wei-Hsien Chen, Kai-Cheung Juang
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Patent number: 8102214Abstract: Provided is controlled-gain wideband feedback low-noise amplifier. The controlled-gain wideband feedback low-noise amplifier includes: a feedback amplifier configured to isolate an input signal and an output signal obtained by amplifying the input signal, feed back the output signal to the input signal to amplify wideband input signals, resonate a low-frequency band signal among the wideband input signals to amplify the low-frequency band signal among the wideband input signals, and be switched in accordance with a control signal to control an amplification gain of the low-frequency band signal among the wideband input signals; and a cascode amplifier configured to amplify a high-frequency band signal among the wideband signals inputted from the feedback amplifier, and be switched in accordance with a control signal to control an amplification gain of the high-frequency band signal among the wideband signals.Type: GrantFiled: August 25, 2010Date of Patent: January 24, 2012Assignee: Electronics and Telecommunications Research InstituteInventors: Bong-Hyuk Park, Kwang-Chun Lee
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Publication number: 20120007681Abstract: A system for a feedback transimpedance amplifier with sub-40 khz low-frequency cutoff is disclosed and may include amplifying electrical signals received via coupling capacitors utilizing a transimpedance amplifier (TIA) having feedback paths comprising source followers and feedback resistors. The feedback paths may be coupled prior to the coupling capacitors at inputs of the TIA. Voltages may be level shifted prior to the coupling capacitors to ensure stable bias conditions for the TIA. The TIA may be integrated in a CMOS chip and the source followers may comprise CMOS transistors. The TIA may receive current-mode logic or voltage signals. The electrical signals may be received from a photodetector, which may comprise a silicon germanium photodiode and may be differentially coupled to the TIA. The chip may comprise a CMOS photonics chip where optical signals for the photodetector in the CMOS photonics chip may be received via one or more optical fibers.Type: ApplicationFiled: July 1, 2011Publication date: January 12, 2012Inventor: Brian Welch
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Patent number: 8089316Abstract: A broadband active circuit with a feedback structure includes: an active load unit providing a load varied according to a control voltage; an active circuit unit connected between the active load unit and a ground and outputting a signal corresponding to a pre-set bandwidth, among input signals; and a feedback circuit unit formed between an output terminal of the active circuit unit and the active load unit and providing a signal from the output terminal of the active circuit unit to the active load unit.Type: GrantFiled: December 23, 2009Date of Patent: January 3, 2012Assignee: Samsung Electro-Mechanics Co., Ltd.Inventors: Chul Gyun Park, Jae Sung Rieh, Dong Hyun Kim
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Publication number: 20110304399Abstract: Disclosed herein is a driver amplifier circuit, including: a first current source transistor of a first conductivity type, and a second current source transistor of the first conductivity type, control voltages being supplied to gates of the first current source transistor and the second current source transistor, respectively; a first switching transistor of the first conductivity type, and a second switching transistor of the first conductivity type; a third switching transistor of a second conductivity type, and a fourth switching transistor of the second conductivity type; first, second, third, and fourth resistor elements; and a first output node and a second output node.Type: ApplicationFiled: July 8, 2011Publication date: December 15, 2011Applicant: Sony CorporationInventors: Hidekazu Kikuchi, Tomokazu Tanaka, Kunio Gosho
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Publication number: 20110291763Abstract: A method for low noise signal amplification includes modifying a signal by way of a first amplification stage and conveying the modified signal to a second amplification stage. The method continues with comparing an output of the second amplification stage with a signal ground in a low-frequency feedback loop and changing a bias voltage for the first amplification stage as a result of the comparing step.Type: ApplicationFiled: May 28, 2010Publication date: December 1, 2011Inventor: David E. Smith
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Publication number: 20110279183Abstract: An electronic circuit includes a linear amplifier unit having a first current feedback loop, assisted by a switched-mode amplification unit having a second current feedback loop. The inputs of the two units are connected so that they receive, at the same time, a current setpoint in an operating mode in order to generate a fixed current across a load connected to the output of the units. The first feedback loop includes a first sensor to measure the current in the load, a first subtractor element to subtract the first measured current from the current setpoint, a first controller connected to the output of the first subtractor element and controlling a linear amplifier, which supplies the first output current to the load. The second feedback loop includes a second current sensor to measure a second current supplied to the load, between a connecting node of two switches connected in series to a supply voltage source and an inductor whose output is connected to the load.Type: ApplicationFiled: May 17, 2011Publication date: November 17, 2011Inventors: Claude Froidevaux, Jean-Marc Vaucher
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Publication number: 20110234320Abstract: A voltage output device which is capable of preventing an increase in circuit scale and includes an offset compensation function that is suitably applicable in particular to a drive circuit for display devices such as liquid crystal display panels. The voltage output device includes an operational amplifier which has an inverting input terminal and a non-inverting input terminal. Resistance values of a load resistor on the inverting input side and a load resistor on the non-inverting input side are maintained when the output voltage of the amplifier has changed while sequentially varying either one or both of the resistance values of the load resistor on the inverting input side and the load resistor on the non-inverting input side in a state that the inverting input terminal and the non-inverting input terminal are connected. The voltage output device is configured to output the output voltage of the amplifier with the inverting input terminal not connected to the non-inverting input terminal.Type: ApplicationFiled: March 17, 2011Publication date: September 29, 2011Applicant: OKI SEMICONDUCTOR CO., LTD.Inventor: Hiroyoshi ICHIKURA
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Publication number: 20110235455Abstract: Circuits, devices and methods are provided, such as an amplifier (e.g., a voltage regulator) that includes a feedback circuit that supplies negative feedback through a feedback path. One such feedback path includes a capacitance coupled in series with a “one-way” isolation circuit through which a feedback signal is coupled. The “one-way” isolation circuit may allow the feedback signal to be coupled from a “downstream” node, such as an output node, to an “upstream” node, such as a node at which an error signal is generated to provide negative feedback. However, the “one-way” isolation circuit may substantially prevent variations in the voltage at the upstream node from being coupled to the capacitance in the isolation circuit. As a result, the voltage at the upstream node may quickly change since charging and discharging of the capacitance responsive to voltage variations at the upstream node may be avoided.Type: ApplicationFiled: March 29, 2010Publication date: September 29, 2011Applicant: Micron Technology, Inc.Inventor: DONG PAN
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Publication number: 20110227648Abstract: Illustrative embodiments of a power amplifier are disclosed which include a plurality of amplifier cells, each having an input and an output. The plurality of amplifier cells are formed on a semiconductor substrate such that the outputs of the plurality of amplifier cells are electrically coupled in series. Each of the plurality of amplifier cells may comprise a first transistor that is electrically insulated from the semiconductor substrate and a first feedback resistor configured to dynamically bias the first transistor.Type: ApplicationFiled: March 10, 2011Publication date: September 22, 2011Inventors: Saeed Mohammadi, Sultan R. Helmi, Jing-Hwa Chen, Andrew J. Robison
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Publication number: 20110221532Abstract: According to an embodiment, a semiconductor integrated circuit device includes an amplifier and a feedback circuit. The amplifier includes an input terminal receiving an input signal and an output terminal outputting an output signal. The feedback circuit includes a first transistor generating a bias current. The feedback circuit is configured to operate based on the bias current. The feedback circuit is configured to receive the output signal to supply a feedback signal to the input terminal. A signal having a reverse phase to the output signal is input to a gate of the first transistor.Type: ApplicationFiled: September 21, 2010Publication date: September 15, 2011Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Junji Wadatsumi
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Publication number: 20110204979Abstract: An apparatus and method include a transmission line carrying a propagating signal between an inlet port and an outlet port. The propagating signal can include a forward traveling wave and optionally a backward traveling wave. A feedback stage samples a the propagating signal at the outlet port, generates a feedback signal the includes a time translation and a gain translation in the feedback energy, and routes the feedback signal to the inlet port such that the gain translation constructively interferes with the forward traveling wave and thereby increases the amplitude of the forward traveling wave.Type: ApplicationFiled: September 24, 2009Publication date: August 25, 2011Applicant: The Regents of the University of CaliforniaInventor: James Buckwalter
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Patent number: 8004360Abstract: The present invention discloses a Class-D power amplifier and control method thereof. In one embodiment, the amplifier feeds back the signal at the output node to the inverting input of the comparator, and provides a high frequency triangular wave signal to the non-inverting input of the comparator. In addition, the non-inverting input of the comparator may be coupled to an offset voltage, while the inverting input of the comparator may be coupled to a fixed-frequency rectangular wave signal, a feedback signal which is derived from the output stage and an input signal. In use, the switching frequency may be at least substantially fixed, so as to reduce the influence on the system caused by electromagnetic interruption (EMI). Further, the control circuit is simple, and some devices can be integrated.Type: GrantFiled: April 23, 2010Date of Patent: August 23, 2011Assignee: Monolithic Power Systems, Inc.Inventors: Junming Zhang, Yuancheng Ren, Yunping Lang
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Patent number: 7999780Abstract: An amplifier circuit includes an operational amplifier having first and second input nodes and one output node which is connected to a data line for which a pixel is provided; a feedback circuit having first and second elements which are connected to one of the first and second input nodes at their one ends; and a first switch section. The first switch section switches an operation mode between a first drive mode in which the other end of the first element is connected to the output node and a second drive mode in which the other end of the second element is connected to the output node.Type: GrantFiled: April 4, 2007Date of Patent: August 16, 2011Assignee: Renesas Electronics CorporationInventors: Yoshiharu Hashimoto, Takayuki Shu, Masayuki Kumeta
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Publication number: 20110181271Abstract: A peaking circuit according to the present invention includes amplifiers connected in multiple stages and feedback circuits for feedback to an input from two or more output points with different gains as seen from the input. The peaking circuit is configured to be able to change an amount of feedback of the feedback circuits.Type: ApplicationFiled: January 26, 2011Publication date: July 28, 2011Inventors: Norio CHUJO, Takehito Kamimura
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Publication number: 20110169568Abstract: The present invention relates generally to an operational amplifier. In one embodiment, the present invention is an operational amplifier including a transimpedance input stage, the transimpedance input stage including a first stage connected to a first resistor and a second resistor, and an output stage connected to the transimpedance input stage.Type: ApplicationFiled: February 3, 2011Publication date: July 14, 2011Inventors: Zachary M. Griffith, Miguel E. Urteaga, Mark J.W. Rodwell
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Publication number: 20110169573Abstract: A step gain amplifier has an amplifier with an input and an output, and a bias circuit connected to the input and to a bias node. A passive feedback circuit using only passive elements connects the output to the input. A control circuit is connected to the bias circuit at the bias node.Type: ApplicationFiled: January 11, 2010Publication date: July 14, 2011Inventors: Bun Kobayashi, Steven W. Schell, Yonghan Chris Kim, Pei-Ming Daniel Chow, Mau-Chung Frank Chang
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Publication number: 20110156818Abstract: An output-impedance in a power amplifier is provided. A first transistor QBUF of a buffer stage is connected to a first side of a resistor RF and a second transistor QAMP to a second opposite side of the resistor RF. The first transistor feeds a current IRF to the second resistor QAMP. The current IRF at the second transistor is copied and multiplied by a factor (n) to form an output current IOUT, as (1+n)* IRF. The current IRF is fed back to the first transistor and the output current IOUT is fed to a load resistor R.Type: ApplicationFiled: December 30, 2009Publication date: June 30, 2011Inventors: Mats Carlsson, Daniel Bjork
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Publication number: 20110143685Abstract: A multiband low noise amplifier (LNA) with parallel resonant feedback includes an amplifier element configured to receive a radio frequency (RF) signal at an RF input and provide an amplified version of the RF signal at an RF output, a resistive feedback circuit coupled between the RF input and the RF output, and a plurality of series-coupled resonant circuits coupled in series with the resistive feedback circuit between the RF input and the RF output of the amplifier element, wherein each of the resonant circuits is configured to operate as an effective short circuit at a frequency other than a resonant frequency and configured to operate as an effective open circuit at the resonant frequency to decouple the resistive feedback from the amplifier element at each resonant frequency.Type: ApplicationFiled: December 10, 2009Publication date: June 16, 2011Inventor: Haki Cebi
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Patent number: 7956691Abstract: A system and method for over-voltage protection of a power amplifier is provided. A power amplifier is typically employed in a transmitter to amplify signals prior to transmission via a load; the load may include an antenna or a cable. As a result of an impedance mismatch between the power amplifier and its load, excess power from the power amplifier output fails to reach the load and must be dissipated by one or more transistors in the power amplifier. In severe impedance mismatch conditions, this dissipated power may damage or destroy the transistor(s). An automatic gain control (AGC) is provided for detecting a gain difference between the power amplifier and a replica power amplifier. A gain difference may signal an over-voltage situation. The AGC may be configured to adjust the gain of the power amplifier if a gain difference exists to prevent device damage.Type: GrantFiled: June 9, 2009Date of Patent: June 7, 2011Assignee: Broadcom CorporationInventors: Ramon Gomez, Flavio Avanzo, Giuseppe Cusmai, Takayuki Hayashi
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Patent number: 7940122Abstract: There is provided an amplifier circuit having a common-source amplifier, an output load connected to an output terminal of the common-source amplifier, a buffer circuit connected to the output terminal of the common-source amplifier, a feedback circuit connected between an output terminal of the buffer circuit and an input terminal of the common-source amplifier, and a control circuit for controlling an impedance of the feedback circuit in accordance with a gain of the common-source amplifier.Type: GrantFiled: July 31, 2008Date of Patent: May 10, 2011Assignee: Fujitsu LimitedInventor: Hiroyuki Satou
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Patent number: 7940120Abstract: The power amplifier mainly includes a main amplifier, two splitters, one combiner, one subtracter, two phase shifters, one attenuator and one error amplifier. The splitters, subtracter and combiner are designed in the form of 90-degree or quadrature hybrid couplers. A quadrature hybrid can be implemented with any lumped or transmission-line elements and has an important advantage compared to the in-phase splitter that at equal values of reflection coefficients from loads connected to the in phase and 90° phase shift terminals, the reflection wave is lacking at the main input terminal and, consequently, the input voltage standing wave ratio of a quadrature hybrid does not depend on the equal load mismatch level.Type: GrantFiled: August 26, 2009Date of Patent: May 10, 2011Assignee: Alcatel LucentInventors: Andrei Grebennikov, Florian Pivit
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Publication number: 20110084766Abstract: A broadband active circuit with a feedback structure includes: an active load unit providing a load varied according to a control voltage; an active circuit unit connected between the active load unit and a ground and outputting a signal corresponding to a pre-set bandwidth, among input signals; and a feedback circuit unit formed between an output terminal of the active circuit unit and the active load unit and providing a signal from the output terminal of the active circuit unit to the active load unit.Type: ApplicationFiled: December 23, 2009Publication date: April 14, 2011Applicant: Samsung Electro-Mechanics Co., Ltd.Inventors: Chul Gyun Park, Jae Sung Rieh, Dong Hyun Kim
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Patent number: 7917106Abstract: An RF power amplifier system comprises an amplitude control loop and a phase control loop. The amplitude control loop adjusts the supply voltage to the power amplifier based upon the amplitude correction signal indicating the amplitude difference between the amplitude of the input signal and an attenuated amplitude of the output signal. The phase control loop adjusts the phase of the input signal based upon a phase error signal indicating a phase difference between phases of the input signal and the output signal. The phase control loop may comprise one or more variable phase delays introducing a relative phase delay to allow the phase differences between the input and output signals of the PA circuit to be within a range compatible with a phase comparator generating the phase error signal, and a low frequency blocking module that removes the larger extent, lower frequency components of the phase error signal.Type: GrantFiled: January 31, 2007Date of Patent: March 29, 2011Assignee: Quantance, Inc.Inventors: Serge Francois Drogi, Vikas Vinayak, Mark Gehring, Cary Renzema, Jeremy Lubkin
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Patent number: 7915958Abstract: An amplifier comprises an input terminal that inputs an AC voltage signal; an amplifying unit having a transistor for amplifying the input AC voltage signal; a current detecting unit connected internally of said amplifying unit; and a control-current source controlled by said current detecting unit that drives an input stage of the transistor.Type: GrantFiled: October 29, 2008Date of Patent: March 29, 2011Assignee: Renesas Electronics CorporationInventor: Hirokazu Ooyabu
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Publication number: 20110063035Abstract: Provided is controlled-gain wideband feedback low-noise amplifier. The controlled-gain wideband feedback low-noise amplifier includes: a feedback amplifier configured to isolate an input signal and an output signal obtained by amplifying the input signal, feed back the output signal to the input signal to amplify wideband input signals, resonate a low-frequency band signal among the wideband input signals to amplify the low-frequency band signal among the wideband input signals, and be switched in accordance with a control signal to control an amplification gain of the low-frequency band signal among the wideband input signals; and a cascode amplifier configured to amplify a high-frequency band signal among the wideband signals inputted from the feedback amplifier, and be switched in accordance with a control signal to control an amplification gain of the high-frequency band signal among the wideband signals.Type: ApplicationFiled: August 25, 2010Publication date: March 17, 2011Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTEInventors: Bong-Hyuk PARK, Kwang-Chun Lee
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Patent number: 7899420Abstract: A wireless transmission device includes a RF power amplification section for amplifying a transmit RF signal and outputting the amplified signal to a transmission antenna, a detector section, and a control section. The RF power amplification section includes a plurality of stages of amplification, the transmit RF signal is input to an input of a first one of the plurality of stages of amplification, and an output of a last one of the plurality of stages of amplification is output to the transmission antenna. The detector section includes a plurality of detectors provided so as to correspond to the plurality of stages of amplification, each for detecting an input level of a corresponding one of the stages of amplification, and a synthesizer for synthesizing together detection outputs from the plurality of detectors. The control section controls, in a feedback control, an output level of the RF power amplification section based on an output level of the synthesizer.Type: GrantFiled: January 15, 2008Date of Patent: March 1, 2011Assignee: Panasonic CorporationInventors: Shigeki Nakamura, Fumiya Kamimura, Junji Ito, Hidefumi Suzaki
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Patent number: RE42846Abstract: The present invention discloses a Class-D power amplifier and control method thereof. In one embodiment, the amplifier feeds back the signal at the output node to the inverting input of the comparator, and provides a high frequency triangular wave signal to the non-inverting input of the comparator. In addition, the non-inverting input of the comparator may be coupled to an offset voltage, while the inverting input of the comparator may be coupled to a fixed-frequency rectangular wave signal, a feedback signal which is derived from the output stage and an input signal. In use, the switching frequency may be at least substantially fixed, so as to reduce the influence on the system caused by electromagnetic interruption (EMI). Further, the control circuit is simple, and some devices can be integrated.Type: GrantFiled: December 14, 2010Date of Patent: October 18, 2011Assignee: Monolithic Power Systems, Inc.Inventors: Junming Zhang, Yuancheng Ren, Yunping Lang