Amplifiers inventions 03/07

20070069811 - Line drivers with extended linearity: Line drivers with extended linearity are described herein. In one embodiment, an example of a line driver includes, but is not limited to, a first amplifier having a first input, a second amplifier having a second input, the first and second amplifiers driving a load of a communication line, and... Agent: Blakely Sokoloff Taylor & Zafman

20070069812 - Input/output signals preserver circuit of amplification circuits: The present invention relates to an input and output signal preservation circuit of an amplification circuit capable of preventing an attenuation of an input signal and an output signal of an amplification circuit in such a manner that an AC input signal is amplified using an amplification device such as... Agent: J.c. Patents

20070069813 - Correlation method for monitoring power amplifier: The invention provides methods and devices for estimating power amplifier nonlinearity using simple correlation techniques. Methods and devices of the invention can monitor a power amplifier that has digitally modulated inputs and an output containing more than one signal stream. A preferred method of the invention creates a test signal... Agent: Greer, Burns & Crain

20070069814 - Self-oscillating driver circuit: A self-oscillating driver circuit comprises a driver stage, a feedforward path which is coupled to an input of the driver stage, and a feedback path which couples an output of the driver stage to an input of the feedforward path. The feedforward path comprises a feedforward filter which is designed... Agent: Maginot, Moore & Beck Chase Tower

20070069815 - Operational amplifier: There is provided an operational amplifier with a broad applicable band and little disturbing noise which is capable of preventing oscillation even when used in connection with a negative feedback path. The present invention relates to an operational amplifier which amplifies a difference between two input voltage signals to a... Agent: Bacon & Thomas, PLLC

20070069816 - Method for transconductance linearization for dc-coupled applications: A Class AB voltage-to-current converter includes a plurality of DC coupled transconductance stages that produce a linearized output and a biasing circuit. The biasing circuit generates a primary bias voltage that is greater than a generated secondary bias voltage. As such, the first transconductance stage becomes active before the second... Agent: Garlick Harrison & Markison

20070069817 - Adaptable voltage control for a variable gain amplifier: A method and apparatus for adaptively controlling a variable gain amplifier (VGA). The operation of the VGA is separated into a low gain mode and a high gain mode and the mode in which the VGA is currently operating in is adaptively sensed. A threshold voltage is compared to a... Agent: Mcandrews Held & Malloy, Ltd

20070069818 - Multilevel power amplifier architecture using multi-tap transformer: A multi-level power amplifier architecture using a multi-tap transformer implemented on a single CMOS integrated circuit wireless communications device is described. By providing a multi-tap transformer for coupling a plurality of power amplifiers to a shared output impedance, such as an antenna, power transmission may be made at different levels... Agent: Garlick Harrison & Markison

20070069819 - Transistor drive circuit, constant voltage circuit, and method thereof using a plurality of error amplifying circuits to effectively drive a power transistor: A transistor drive circuit, a constant voltage circuit, and a method thereof provided with a reference voltage generator, a power voltage detector, and a plurality of error amplifying circuits. The plurality of error amplifying circuits have different operational characteristics. One of the error amplifying circuits is selectively activated in response... Agent: Cooper & Dunham, LLP

20070069820 - Electronic parts for high frequency power amplifier: An electronic part for a high frequency power amplifier is provided which is designed to constitute at least a part of a wireless communication system for performing feedback control by detecting an output power, and which can miniaturize a directional coupler. Also, the electronic part permits control of the output... Agent: Mattingly, Stanger, Malur & Brundidge, P.C.

20070069821 - Active balun device: An active balun device is provided. The active balun device includes: a differential input portion for receiving an external single input signal to output two complementary differential signals; and a differential amplifier connected to the differential input portion in cascade to amplify the two differential signals received from the differential... Agent: Ladas & Parry LLP

20070069822 - Device for measuring very short current pulses: The invention relates to the measurement of current pulses that are very brief (a few nanoseconds) and of very low amplitude (a few microamps), such as those that can emanate from a photodetector used for the optical transmission of data at very high speed, or from a photodetector (photodiode or... Agent: Lowe Hauptman Gilman & Berner, LLP

20070063764 - Class ad audio amplifier: An audio amplifier comprising a Class D audio amplifier having an input receiving an analog input signal, a pulse width modulation stage for converting the analog input signal to a pulse width modulated signal, a driver stage receiving the pulse width modulated signal and for producing a driver PWM signal... Agent: Ostrolenk Faber Gerb & Soffen

20070063765 - Power control and modulation of switched-mode power amplifiers with one or more stages: This invention controls and modulates switched-mode power amplifiers to enable the production of signals that include amplitude modulation (and possibly, but not necessarily, phase modulation), the average power of which may be controlled over a potentially wide range.... Agent: Mcdermott Will & Emery LLP

20070063767 - Bypassable low noise amplifier topology with multi-tap transformer: An amplifier is disclosed that contains a transistor (BJT), a switch (MOSFET), and a transformer. The collector of the BJT is connected to an end of the transformer while the base of the BJT is connected to a point between the ends of the transformer through the MOSFET. When the... Agent: Brinks Hofer Gilson & Lione

20070063766 - High-frequency amplifier: It is an object of this invention to provide a high-frequency amplifier which can efficiently amplify an input signal in a plurality of different frequency bands in a simple configuration. The high-frequency amplifier is configured such that an RF signal having n frequencies (f1>f2 , , , >fn) applied to... Agent: Foley And Lardner LLP Suite 500

20070063768 - Ac amplifier and piezoelectri vibrator oscillator: An AC amplifier has an amplification circuit, and a bias circuit connected together by connecting wiring. The bias circuit receives an input of an AC signal from the amplification circuit via the connecting wiring. A DC voltage of the bias circuit conformed to the amplitude of the AC signal of... Agent: The Webb Law Firm, P.C.

20070063772 - Amplifier system employing analog polynomial predistortion with sub-nyquist digital adaptation: A predistortion linearized amplifier system that uses analog polynomial based predistortion is disclosed. An analog polynomial function generator receives polynomial parameter updates from a polynomial parameter generator. The polynomial parameter generator uses a combination of analog and digital signal processing to create the parameter updates. This processing is performed on... Agent: Myers Dawes Andras & Sherman, LLP

20070063769 - Arrangement and method for digital predistortion of a complex baseband input signal: A system and a method create a pre-distorted signal y(k) from an interpolated broadband baseband signal x(k) for a transmitter power amplifier having at least three branches to which the signal x(k) is respectively connected on the input side. A first branch contains a distortion device for taking into account... Agent: Staas & Halsey LLP

20070063771 - Bias-t circuit: A bias-T circuit including a radio frequency signal input device and a dc bias input device connected in parallel with an output. The radio frequency signal input device includes a capacitive element in series with the output. The dc bias input device includes a radio frequency transistor for controlling the... Agent: Sughrue Mion, PLLC

20070063770 - Power amplifier pre-distortion: A power amplifier pre-distorter is formed by a FIR filter structure which includes an individual look-up table for each filter tap, where each look-up table represents a sampled polynomial in a variable representing signal amplitude, and means for selecting, from each filter tap look-up table, a filter coefficient that depends... Agent: Nixon & Vanderhye, PC

20070063773 - Method and apparatus for reducing ripple in class d amplifiers: Class D amplifiers are used for their high efficiency, but they have some undesirable characteristics, one of these being the residual switching frequency ripple. Embodiments of the present invention comprise methods and apparatuses for reducing the switching frequency ripple using a technique known herein as ripple steering. A secondary output... Agent: The Hecker Law Group

20070063774 - Method and apparatus for controlling the output power of a power amplifier: A method and apparatus is provided for use with a power amplifier to provide a regulated supply to the power amplifier. The invention uses a combination of voltage and current regulation to overcome the problems encountered in the prior art. In one example, voltage regulation is used at high power... Agent: Johnson & Associates

20070057721 - System for amplifiers with low distortion and low output impedance: System for pulse-width-modulated class D audio amplifiers. In one preferred embodiment an adder is described to generate a difference signal responsive to an input signal and a feedback signal, a pulse-width-modulator coupled to the adder to compare the difference signal to a reference signal and produce a pulse-width-modulated signal based... Agent: Texas Instruments Incorporated

20070057720 - Systems and methods for load detection and correction in a digital amplifier: Systems and methods for detecting the impedance of an output load coupled to a digital amplifier and compensating for changes in the response of the amplifier. One embodiment of the invention is implemented in a Class D pulse width modulated (PWM) amplifier. In this embodiment, a digital PCM test signal... Agent: Law Offices Of Mark L. Berrier

20070057722 - Power amplification apparatus of a portable terminal: The present invention relates to a power amplification circuit of a mobile device for improving the efficiency and the linearity properties of the power amplifier. In one embodiment, the power amplifier improves these properties by controlling the input voltage of the supplemental amplifier so that the power amplifier operates as... Agent: Avago Technologies, Ltd. C/o Klaas, Law, O'meara & Malkin, P.C.

20070057723 - High performance input receiver circuit for reduced-swing inputs: An input buffer receiver circuit for electronic devices (e.g., memory chips) to receive and process reduced-swing and high bandwidth inputs to obtain “buffered” output signals therefrom with symmetrical rising and falling delays, and without additional current dissipation over previous receiver circuits, is disclosed. The receiver circuit may include two stages... Agent: Jones Day

20070057724 - Operational amplifier: An operational amplifier 1 is provided with differential amplifier 2, replica amplifier 3, voltage-current converting circuit 4, reference current source 5 and comparator 6. Differential amplifier 2 includes P-channel MOS transistors PT1 and PT2, gate and drain electrodes of which are connected to each other to function as loads, and... Agent: Oblon, Spivak, Mcclelland, Maier & Neustadt, P.C.

20070057725 - Selective differential low-noise amplifier: A selective differential low-noise amplifier includes a pair of transistors, each transistor of the pair being connected by its source to a current source and by its gate and/or its source to a differential voltage source, a coupling circuit between the gate of each transistor and the source of the... Agent: Jacobson Holman PLLC

20070057726 - Amplification circuit improved with linearity and frequency converter using the same: Provided is a frequency converter using an amplification circuit that is improved with linearity by coupling a main transistor and an auxiliary transistor in parallel. An amplification circuit that is improved with linearity comprises an input block amplifying an input signal, an induction block inducing a current proportionate to an... Agent: Foley And Lardner LLP Suite 500

20070057727 - Differential operational amplifier: Disclosed is a differential operational amplifier that outputs first and second output voltages corresponding to first and second input voltages, the amplifier comprising a differential circuit that operates depending on the first and second input voltages; a control voltage generation circuit that generates a control voltage for making an intermediate... Agent: SocalIPLaw Group LLP

20070057728 - Method and arrangement for adjusting an output impedance of a power amplifier: The invention relates to power amplifiers having an adjustable output impedance. A power amplifier according to the invention can be used, for example, for feeding a radio frequency transmission signal into an antenna of a mobile communication device. The real part of an output impedance of a power amplifier according... Agent: Ware Fressola Van Der Sluys & Adolphson, LLP

20070057729 - Power amplifier and wireless communication device: There are provided a power amplifying transistor, a bias circuit which supplies a bias current to the base of the power amplifying transistor, a current mirror circuit which detects a peak value of the collector voltage of the power amplifying transistor, and a control circuit which, when the peak value... Agent: Leydig Voit & Mayer, Ltd

20070057730 - Margin tracking cascode current mirror system and method: A margin tracking cascode current mirror system including a current mirror circuit having a current source device having a predetermined operating voltage for providing a current to a load, a cascode circuit interconnected between the current mirror and the load for controlling the output impedance of the system and for... Agent: Iandiorio & Teska

20070057731 - On-chip harmonic termination for rf power amplifier applications: A radio frequency (“RF”) amplifier as disclosed herein includes an on-chip power transistor formed on a substrate and an on-chip harmonic termination formed on the same substrate. The on-chip harmonic termination is configured to provide a short-circuit termination for even harmonics of the RF output signal and to provide an... Agent: Ingrassia, Fisher & Lorenz, P.C.

20070057732 - Ota-based high-order filters: Nth-order OTA-C (Operational Transconductance Amplifiers and Capacitors) filter structures are realized by using the analytical synthesis method to achieve the following three important criteria simultaneously: filters use just n grounded capacitors, each of which is located at each of just n nodes in the realized circuit, because they use smaller... Agent: Hdsl

20070057733 - Low noise amplifier with switch gain control: This invention presents a low noise amplifier with switching gain control, comprising an amplifier having an impedance matching circuit a switch circuit, a signal amplifying branch circuit, a switch control circuit, a signal attenuating circuit and a current bias circuit, wherein the switch circuit controls signal amplifying or attenuating based... Agent: Law Offices Of Clement Cheng

20070052474 - Amplifier and device having amplifier, and mutual conductance control method: An amplifier is provided with an amplifier circuit including a plurality of first transistors having gates thereof coupled in common, a bias circuit including a plurality of second transistors that are coupled and outputs a bias voltage to the gates of the plurality of first transistors, and a selection circuit... Agent: Arent Fox Pllc

20070052475 - Method and apparatus for combining multiple signals for high efficiency applications: Methods and apparatus are provided for efficiently combining and filtering a plurality of input signals into a single combined output signal. M number of input signals are received, combined and filtered by a filter/combiner. The filter/combiner has a plurality of input stages for each input signal, and an output stage... Agent: Docket Clerk

20070052476 - Charging circuit and control method and integrated circuit utilizing the same: A charging circuit for a bridge tied load (BTL) including an amplifier and a load driven by the amplifier according to a voice signal and a reference voltage stored in a reference capacitor. The charging circuit comprises a power supply and a comparison unit. The power supply provides one of... Agent: Birch Stewart Kolasch & Birch

20070052477 - Efficient power supply for rapidily changing power requirements: A highly efficient power supply, a method for supplying power, and a method for arranging a power supply, for a UHF or microwave radio frequency amplifier intended for operation with a signal that has a power level which varies at a high frequency rate. The power supply has an output... Agent: Young & Thompson

20070052478 - Low distortion class-d amplifier using carrier reference signal symmetry modulation.: An electronic class-D amplifier with intrinsically low distortion employing modulation of the slopes of a triangular-wave carrier reference signal; the modulation being in proportion to the derivative of the input signal. The negation of the distortion is most successful if this derivative signal is shifted in phase and gain to... Agent: Osha Liang L.l.p.

20070052479 - Dynamic bias circuit for a radio-frequency amplifier: A dynamic bias circuit for an RF amplifier is provided to overcome the drawbacks of conventional bias circuits. The dynamic bias circuit of the present invention is best used for an RF amplifier having an FET amplifying transistor. It automatically raises the DC bias point as the input power increases.... Agent: Lin & Associates Intellectual Property

20070052480 - Circuit which can be programmed using a resistor and which has a reference current source: A circuit configured to be programmed using a resistor includes an output terminal, a reference voltage source, a first circuit, and a current mirror arrangement. The output terminal is configured to be connected to a programming resistor. The reference voltage source is configured to generate a reference voltage on the... Agent: Harold C. Moore Maginot, Moore & Beck

20070052481 - Method and apparatus for protecting rf power amplifiers: Method and apparatus are provided for protecting radio frequency (RF) power amplifiers. A circuit (10) is provided for limiting a supply current to a first stage (Q3) of the RF power amplifier having a second stage (Q2) coupled to the first stage. The circuit comprises a comparator (14) having first... Agent: Ingrassia, Fisher & Lorenz, P.c.

20070052482 - Low noise amplifier for a radio receiver: In one embodiment, the present invention includes an amplifier having a transistor stage coupled between a supply voltage and a bias current. The transistor stage has an input to receive a radio frequency (RF) input signal obtained from an antenna. The amplifier has an input impedance that is unmatched to... Agent: Trop Pruner & Hu, Pc

20070046368 - Circuit for creating tracking transconductors of different types: Systems and method for tracking different types of transconductance cells is shown and described. In these multi-cell systems, the addition of one or more tracking control modules allows circuit designers to advantageously incorporate multiple transconductor topologies and their uniquely beneficial characteristics into their designs, without eradicating its centralized multi-cell tuning... Agent: Marger Johnson & Mccollom, P.C.

20070046367 - Method and apparatus for presetting an amplifier: An output of a common mode differential amplifier is initialized to a known state, which includes inputting a voltage to a network conductor of an electronic assembly, where the network conductor is coupled to a first input node of a first differential input of the amplifier. The amplifier is on... Agent: Ibm Burlington (ave) C/o Law Office Of Anthony England

20070046369 - High sensitivity rfid tag integrated circuits: A method and apparatus for an ultra-high sensitivity, low cost, passive (no battery) low-power energy harvesting data transmitting circuit energy, such as a RFID (Radio Frequency IDentification) tag integrated circuit “chip.” By using combinations of special purpose design enhancements, the low-power energy harvesting passive data transmitting circuit, such as the... Agent: Christie, Parker & Hale, LLP

20070046370 - High-frequency power amplifier: In a base-bias-control-type high-frequency power amplifier with a plural stage configuration, a rising voltage of a base bias current supplied to an initial stage transistor is made lower than a rising voltage of a base bias current supplied to a second stage transistor by a bias circuit, and a difference... Agent: Miles & Stockbridge PC

20070046371 - Power amplifier: A radio frequency power amplifier including control electronics for providing control signals for timing of the power amplifier. A first group of the drivers are coupled to the control electronics and a second group of drivers are coupled to the control electronics. The first group of drivers operate in response... Agent: Patrick W. Rasche Armstrong Teasdale LLP

20070046372 - Portable electronic unit: To provide a portable electronic unit that can reduce power consumption. A high-frequency amplification circuit amplifies heart rate information received by an antenna and detects the information by means of a detection circuit. A gain control circuit controls a gain in a gain control amplification circuit in two steps in... Agent: Bruce L. Adams, Esq.

20070046373 - Input buffer design using common-mode feedback (cmfb): An input buffer includes a first stage for receiving an input signal and having a first pair of complementary output signals, the first stage including an input circuit for receiving the input signal, an output circuit for generating the first pair of complementary output signals based on the input signal,... Agent: Dickstein Shapiro LLP

20070046374 - Linearity-improved differential amplification circuit: A linearity-improved differential amplification circuit is provided, A linearity-improved differential amplification circuit comprises a main differential amplification unit differentially amplifying a first and a second input signals, a main bias unit biasing the main differential amplification unit, a first current source coupled in series between a power supply voltage terminal... Agent: Foley And Lardner LLP Suite 500

20070046375 - Method and device for automatic gain control with limited jitter: The invention concerns controlling automatic gain control for a digital signal receiver. The method includes receiving a digital feedback signal for controlling an amplifier and processing the digital feedback signal to deliver a driving signal to an analog amplifier. Processing the digital feedback signal comprises regulating the evolution of the... Agent: Mckenna Long & Aldridge LLP

20070046376 - Neutralization of feedback capacitance in amplifiers: A transistor amplifier circuit has a current to current feedback transformer for neutralization of feedback capacitance and setting the input impedance of the amplifier. IM3 cancellation is implemented by out-of-band terminations at the input, which does not depend on the loading of the output of the amplifier. The IM3 cancellation... Agent: Philips Intellectual Property & Standards

20070046377 - Power distribution and biasing in rf switch-mode power amplifiers: Methods of and apparatus for distributing power and biasing RF PAs. A power distribution network includes a pre-final amplifier stage power distribution network and a final amplifier stage power distribution network. The pre-final amplifier stage power distribution network includes one or more pre-final amplifier stage power distribution branches, which may... Agent: Mcdermott Will & Emery LLP

20070046379 - Cascode connection circuit: A cascode connection circuit includes a first field effect transistor (FET) which has a source terminal and a drain terminal, the source terminal being connected to ground; a second FET which has a source terminal and a gate terminal, the source terminal being connected to the drain terminal of the... Agent: Leydig Voit & Mayer, Ltd

20070046378 - Operational amplifier output stage and method: An operational amplifier includes an input stage for producing a a voltage signal in response to an input signal. An output stage includes an output transistor having a source coupled to a supply voltage and a gate coupled to receive the voltage signal. An output cascode transistor has a source... Agent: Texas Instruments Incorporated