Amplifiers inventions 02/08

20080048773 - Method and apparatus for dc offset cancellation in amplifiers: A system, circuit, and method of canceling DC offset errors in cascaded amplifiers comprises arranging a plurality of any of analog voltage and analog current amplifier stages in any of cascaded and parallel configurations; operatively connecting a feedback comparator and digital logic in a feedback path around a given amplifier,... Agent: Gibb & Rahman, LLC

20080048774 - High efficiency load insensitive power amplifier: An advanced balanced RF power amplifier circuit is provided. The RF power amplifier has a pair of RF amplification paths constructed to efficiently operate in a high-power mode. When instructed to operate in a low-power mode, one of the amplification paths is deactivated, and optionally, an impedance device is also... Agent: William J. Kolegraff

20080048775 - Auto gain control circuit: An auto gain control circuit comprises a first peak detector, a variable gain amplifier, a second peak detector, a multiplexer and a controller. The first peak detector detects peaks of an input signal to generate a first peak signal. The variable gain amplifier amplifies the input signal to generate an... Agent: Birch Stewart Kolasch & Birch

20080048776 - Methods and systems for stabilizing an amplifier: The invention generally relates to stabilizing an MRI power delivery system. In one aspect, a stabilization module that is in electrical communication with the MRI power delivery system is provided. The stabilization module includes a closed loop control system. The closed loop control system is used to modify the at... Agent: Proskauer Rose LLP

20080048777 - Semiconductor device: 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.... Agent: Mattingly, Stanger, Malur & Brundidge, P.C.

20080048778 - Amplifier with common-mode feedback circuit: A common-mode feedback circuit is provided. An amplifier with a common-mode feedback circuit is compensated by adding a compensating unit so that the amplifier totally has two poles and one zero in its frequency response. Accordingly, the gain of the amplifier is not sacrificed, and both the stability and the... Agent: Birch Stewart Kolasch & Birch

20080048779 - Active emi suppression circuit: A network device comprises an interface coupling an electronic device to a differential pair of signal lines, and an active common mode suppression circuit coupled to the interface in parallel to differential signal lines of the electronic device.... Agent: Koestner Bertani LLP

20080048780 - Linearization apparatus of triode region type operational transconductance amplifier: Provided is a linearization apparatus of a triode region type operational transconductance amplifier that can provide a wide linear input range even when a differential pair input transistor having a short channel length is used at a low power supply voltage. The linearization apparatus of the triode region type operational... Agent: Blakely Sokoloff Taylor & Zafman

20080048781 - Circuit arrangement and method for setting an analog output signal: A circuit arrangement includes a signal processing unit and a regulation unit. The signal processing unit processes an input signal to form an analog output signal. The regulation unit is coupled to the signal processing unit in order to produce a digital regulation signal as a function of the analog... Agent: Eschweiler & Associates LLC

20080048782 - Circuit and method of establishing dc bias levels in an rf power amplifier: A method and apparatus is used to provide DC stabilization and noise reduction in a multistage power amplifier. The invention uses various feedback techniques to stabilize DC levels, which helps to reduce noise. The invention also uses other techniques to reduce noise, and to reduce the noise transfer function in... Agent: Johnson & Associates

20080048783 - Bias circuit: A bias circuit that supplies bias voltage or bias current to one end of a transmission line includes an inductor that prohibits a high frequency component of a baseband signal transmitted on the transmission line and passes a frequency component near direct current of the baseband signal, and an impedance-decrease... Agent: Birch Stewart Kolasch & Birch

20080048784 - Medium voltage or high voltage audio power amplifier and protection circuit: A circuit for a power amplifier includes a main amplifier stage having an operational amplifier (110), a buffer NPN transistor (126) and an NPN transistor (127) connected in a totem pole configuration, and a buffer PNP transistor (133) and a PNP transistor connected in a totem pole configuration. The transistors... Agent: Carlson, Gaskey & Olds, P.C.

20080048785 - Low-noise amplifier: Various embodiments of a two-stage low noise amplifier (LNA) having a gain that can be adjusted without varying input its impedance are disclosed. For example, in an illustrative embodiment, an exemplary low noise amplifier can include an input stage that includes a first transistor, and an output stage that includes... Agent: Kathy Manke Avago Technologies Limited

20080042743 - Differential input class d amplifier: A differential input Class D audio power amplifier incorporating a differential error amplifier is introduced. In response of differential input signal, this differential error amplifier generates two error signals, which subsequently generates final output signal. This architecture makes it the effect of feedback signal error correction doubled, which helps in... Agent: Greenblum & Bernstein, P.L.C

20080042744 - Output circuit of vacuum-tube amplifier: An output circuit of a vacuum-tube amplifier is disclosed. An output circuit of a conventional vacuum-tube amplifier has shortcomings that a front end amplification unit uses a coupling condenser or a transformer to output an AC signal to an output node, a bias voltage of a cathode of a vacuum... Agent: Joseph Hyosuk Kim, Ph.d. Jhk Law

20080042746 - Sigma-delta based class d audio or servo amplifier with load noise shaping: An amplifier capable of driving an analog load is provided. The amplifier can be constructed and arranged to operate as at least one circuit selected from the group consisting of a class D amplifier, voltage regulator, audio amplifier, servo amplifier, servo control, digital control, switching power supply, and switching power... Agent: Daly, Crowley, Mofford & Durkee, LLP

20080042745 - Sigma-delta based class d audio power amplifier with high power efficiency: An amplifier capable of driving an analog load is provided. The amplifier comprises a sigma delta modulator (SDM), a pulse processing circuit, an output stage, and a feedback loop. The SDM produces a plurality of noise-shaped output pulses based upon a digital input signal to the amplifier and an error... Agent: Daly, Crowley, Mofford & Durkee, LLP

20080042747 - Current source circuit and differential amplifier: A current source block and a negative resistance generation block are connected in parallel. The negative resistance generation block generates a negative resistance in response to the minute variations of an output voltage. Thus the output resistance of a current source circuit is given by the combined resistance of the... Agent: Mcdermott Will & Emery LLP

20080042748 - Db-linear variable voltage gain amplifier: A variable voltage gain amplifier in an automatic voltage gain control circuit includes a denominator current source that generates a denominator current corresponding to a denominator a numerator current source that generates a numerator current corresponding to a numerator, and a differential amplifier that amplifies an input voltage with a... Agent: F. Chau & Associates, LLC

20080042749 - Silicon-on-insulator differential amplifier circuit: A differential amplifier formed on a silicon-on-insulator substrate, including means to prevent the bodies of its differential input transistors from charging to unwanted potentials in the standby state. In one aspect of the invention, the means takes the form of switching transistors inserted between the differential input transistors and their... Agent: Nixon Peabody, LLP

20080042750 - Apparatus and method for regulating the output power of an amplifier stage: The present invention relates to a device and a method for regulating the output power of an amplifier stage, e.g. an amplifier stage in a mobile data transmission system.... Agent: Infineon Technologies Ag Patent Department

20080042751 - Non-uniform distributed multi-stage circuits: Provided herein is a non-uniform multi-stage distributed circuit capable of operation with an improved gain-bandwidth product. The circuit can include an input port, an output port and a transmission line coupled therebetween. Two or more amplifier stages can be coupled successively to the transmission line. Each amplifier stage can include... Agent: Orrick, Herrington & Sutcliffe, LLPIPProsecution Department

20080042752 - Current limit circuit for compensating for output load mismatch of a rf power amplifier: An apparatus and method is disclosed for providing control of current consumption of a power amplifier. The power amplifier comprises an output stage for amplifying a RF signal, and the output stage is operably coupled to an output load. The power amplifier further comprises a bias circuit operably coupled to... Agent: Booth Udall, PLC

20080036532 - Transmitter power amplifier working at different power supplies: A method to reduce transmitted output power and the battery consumption is provided. This involves first determining the required output level. The amplitude of the input signal provided to a PA driver may be based on the required output power level. This amplitude may be set by a PGA. A... Agent: Garlick Harrison & Markison

20080036533 - Multi-path doherty amplifier and control method of a multi-path doherty amplifier: Embodiments of the present invention may provide a Doherty amplifier that includes a first amplifying path and at least one second amplifying path. The first amplifying path may include a carrier amplifier to amplify an input signal in a Class 1 mode. The second amplifying path may include a supplementary... Agent: Ked & Associates, LLP

20080036534 - Power amplifier circuit having a bias signal inputted into input terminal and method thereof: The present invention discloses an adjustable gain power amplifier circuit. The adjustable gain power amplifier circuit includes a power amplifying unit for receiving and amplifying an input signal to generate an output signal; a power detecting unit for detecting power of the input signal to generate a detecting signal; and... Agent: North America Intellectual Property Corporation

20080036535 - Amplifying circuit of semiconductor integrated circuit: An amplifying circuit of a semiconductor integrated circuit includes a data amplifier that outputs an up-signal and a down-signal amplified according to a comparison result between an up-data signal and a down-data signal in response to a control signal. The data amplifier repeats an operation of amplifying the up-signal and... Agent: Venable LLP

20080036536 - System and method for linearizing a cmos differential pair: An integrated receiver with channel selection and image rejection substantially implemented on a single CMOS integrated circuit. A receiver front end provides programmable attenuation and a programmable gain low noise amplifier. LC filters integrated onto the substrate in conjunction with image reject mixers provide image frequency rejection. Filter tuning and... Agent: Sterne, Kessler, Goldstein & Fox P.l.l.c.

20080036537 - Wide-band low-noise cmos amplifier: A CMOS low-noise wide-band amplifier (LNA) 211 is provided. The LNA can include a Gm doubler 410, a source follower 420, and a coupling circuit (430/440) that couples a differential input to the Gm doubler with the source follower for achieving high linearity over a wide frequency range at a... Agent: Motorola, Inc Intellectual Property Section

20080036538 - Rail-to-rail class ab amplifier: A rail-to-rail class AB amplifier includes an input circuit for converting a voltage difference between a first input signal and a second input signal into respective currents, a first current adder circuit for adding a drain current of a first input NMOS transistor and a drain current of a second... Agent: F. Chau & Associates, LLC

20080036539 - Power amplifier circuit and test apparatus: Power amplifier circuit outputs an output voltage corresponding to an input voltage supplied, and includes positive and negative-side output units including a positive or negative-side output resistor and a positive or negative-side transistor having its source terminal connected to one end of the positive or negative-side output resistor to make... Agent: Jianq Chyun Intellectual Property Office

20080036540 - Amplifier arrangement and method for amplifying a signal: An amplifier arrangement and a method for amplifying a signal. A transistor (1) is used to amplify an input signal (inp) and to provide an intermediate signal (out1). The intermediate signal is amplified to form an output signal (out) which is fed back to the transistor (1).... Agent: Cohen Pontani Lieberman & Pavane LLP

20080036541 - Bias circuit for maintaining high linearity at cutback power conditions: To improve operation during cutback power mode by reducing gain expansion, sections of a multi-section amplifier are selectively biased. During cutback power condition, fewer than all sections of the multi-section amplifier are biased. Selective biasing reduces power consumption and obtains desired output power. To reduce gain expansion, a bias resistor... Agent: Weide & Miller, Ltd.

20080036542 - Power supply device for driving an amplifier: A power supply device for driving an amplifier includes a first power generator, a second power generator, a charge pump and a control unit. The first power generator is used for providing a first voltage for a first power reception end of the amplifier. The second power generator is used... Agent: North America Intellectual Property Corporation

20080030266 - Limiting amplifiers: A limiting amplifier with an input stage with dc offset cancellation, identical gain stages, an output buffer and a feedback filter. The input stage receives a differential input signal and outputs a first intermediate differential signal. The gain stages are cascaded to amplify the first intermediate differential signal and generate... Agent: Thomas, Kayden, Horstemeyer & Risley, LLP

20080030267 - Class-d audio amplifier with half-swing pulse-width-modulation: An amplifier includes a first comparator, a second comparator, and an output switch. The first and second comparators respectively compare a pair of differential signals with a half-swing modulation signal to generate first and second pulse-width-modulation (PWM) control signals, wherein a voltage swing of the half-swing modulation signal is smaller... Agent: Duane Morris, LLPIPDepartment

20080030268 - Multi-channel, multi-power class d amplifier with regulated power supply: Methods and apparatus are disclosed to reduce the size, weight, and heat loss of power modules mountable in loudspeakers. Disclosed embodiments replace conventional linear technology with high frequency switching technology in both the power supply and amplifier. In these embodiments Class-D switching occurs at a low and fixed frequency, using... Agent: Perkins Coie LLP Patent-sea

20080030269 - Distortion compensator and wireless communication device: A distortion compensator, comprising a distortion component generator that generates a distortion component orthogonal baseband signal corresponding to a nonlinear distortion component based upon an analog orthogonal baseband signal, a distortion component synthesizer that synthesizes a composite signal by combining the analog orthogonal baseband signal and the distortion component orthogonal... Agent: Finnegan, Henderson, Farabow, Garrett & Dunner LLP

20080030270 - Startup and shutdown click noise elimination for class d amplifier: A method of minimizing an audible click noise from a speaker in a Class D audio power amplifier upon shutdown or startup of a switching stage having two switches series connected at a node, the speaker being connected to the node via an output filter comprising an inductor and a... Agent: Ostrolenk Faber Gerb & Soffen

20080030271 - Stereo separation adjustment circuit and mos integrated circuit thereof: A stereophonic separation can be adjusted without narrowing the dynamic range. Between the sources of a MOS transistor (Q5), to which a composite signal is inputted, and a MOS transistor (Q6), to which a reference voltage is inputted, there are connected in parallel the series connections of resistors and switch... Agent: Woodcock Washburn LLP

20080030272 - Amplifier with improved compensation topology and related amplifier circuit, system, and method: An embodiment of an amplifier includes an amplifier output node operable to provide an output signal, and an output stage. The output stage includes a drive buffer having an input node and an output node, a drive transistor, and a compensation capacitor. The drive transistor has a control node coupled... Agent: Bryan A. Santarelli Graybeal Jackson Haley LLP

20080030273 - Active load with adjustable common-mode level: A differential preamplifier includes an active load with adjustable common-mode output level. The active load includes a transistor pair, a resistor pair, and a current source. The transistor load is employed to provide high gain, low offset, and a large bandwidth for the differential preamplifier. The resistor pair and current... Agent: Sterne, Kessler, Goldstein & Fox P.l.l.c.

20080030274 - Gate bias generator: The problem to be solved is incomplete compensation of threshold voltage spreading in amplifier FETs for example in MMIC's. The problem is solved in a gate bias circuit comprising a first constant current source (I1) connected between the gate of an amplifier FET (T1) and a second voltage source (V2),... Agent: Leydig Voit & Mayer, Ltd

20080030275 - Compensation of an amplifier comprising at least two gain stages: An embodiment of an amplifier circuit comprising a succession of amplification stages having at least a first amplification stage receiving a first signal and a second amplification stage downstream of the first amplification stage; a stage of unity gain capable of receiving the first signal and of providing a second... Agent: Bryan A. Santarelli Graybeal Jackson Haley LLP

20080030276 - Multi-mode power amplifier with high efficiency under backoff operation: A multi-mode RF amplifier is disclosed having high and low output power modes and two power paths. A first RF amplifier delivers power to both paths. When the multi-mode RF amplifier is biased into the high power, HP, mode, substantial power is delivered via both (first and second) paths. While... Agent: Cesari And Mckenna, LLP

20080030277 - Power amplifier with output voltage compensation: A power amplifier to provide a compensated output voltage to a load through a series-connected impedance. The power amplifier includes an inner positive current feedback loop that is capable of sensing changes in the resistance of the load, and which adjusts the effective impedance of the series-connected impedance seen by... Agent: Lowrie, Lando & Anastasi

20080030278 - Distributed amplifier having a variable terminal resistance: A distributed amplifier is disclosed herein, which includes a signal amplification unit amplifying a RF input signal fed into the RF signal, a first biasing circuit providing a direct current (DC) bias signal, a second biasing circuit providing a DC bias signal, the variable terminal resistance providing an adjustable resistance,... Agent: Birch Stewart Kolasch & Birch

20080030279 - Circuit with q-enhancement cell having feedback loop: According to an example embodiment, an amplitude feedback loop may include an RF amplifier, a detector, a comparator, and a Q-enhancement cell. In an example embodiment, the RF amplifier has an output signal, and the detector has an input coupled to the output signal of the RF amplifier and is... Agent: Brake Hughes Bellermann LLP C/o Intellevate

20080030280 - Circuits and methods for implementing transformer-coupled amplifiers at millimeter wave frequencies: Circuits and methods are provided for building integrated transformer-coupled amplifiers with on-chip transformers that are designed to resonate or otherwise tune parasitic capacitances to achieve frequency tuning of amplifiers at millimeter wave operating frequencies.... Agent: Frank Chau, Esq. F. Chau & Associates, LLC