Amplifiers inventions 11/07

20070273437 - Driving device: Output signal waveform having high input signal reproducibility is outputted from inductive load or the like. Output signals V1a and V1b obtained by feeding back an output signal Vp-n1 at output terminals 50 and 51 across load L1 to input terminals 9a and 9b are compared with an input signal... Agent: Finnegan, Henderson, Farabow, Garrett & Dunner LLP

20070273436 - Pwm modulator and class-d amplifier having the same: A pulse width modulation (PWM) modulator includes an integrator generating an integrated signal based on an input signal and an output signal, a low pass filter (LPF) receiving the integrated signal and performing low pass filtering, a comparator receiving an output signal of the LPF and a predetermined reference signal,... Agent: F. Chau & Associates, LLC

20070273438 - Mode selection amplifier circuit usable in a signal acquisition probe: A mode selection amplifier circuit has multiple differential amplifier circuits coupled to receive input signals A, B and C. Each differential amplifier circuit is selectively operable for generating a signal output representative of an output mode with the output mode of each differential amplifier circuit selected from one of algebraic... Agent: William K. Bucher Tektronix, Inc.

20070273439 - Apparatus and method of dynamically adapting the lut spacing for linearizing a power amplifier: This invention is about a DAPD-LUT technique of dynamically adapting an LUT spacing for linearizing a power amplifier (PA). It optimizes the LUT spacing for the PA without prior knowledge of system state information. A size-N LUT divides a whole unsaturated PA input amplitude range into N bins, each predistorted... Agent: Lin & Associates Intellectual Property, Inc.

20070273440 - Digital amplifier: Recently, the use of class D audio amplifiers has become more and more widespread. In contrast to the generally employed class AB linear amplification technology, class D allows for improved efficiency. However, the class D principle is known for its poor distortion characteristics. According to the present invention, switching delays... Agent: Nxp, B.v. Nxp Intellectual Property Department

20070273442 - High-efficiency class-ab amplifier: A high efficiency class-AB amplifier is disclosed. The amplifier comprises a first input stage and a second input stage, both coupled to a class-AB biasing mesh and an output stage, wherein the outputs of the first and second input stages are directly coupled to the output transistors in the output... Agent: Sterne, Kessler, Goldstein & Fox P.l.l.c.

20070273441 - Amplifier: The objective of the invention is to automatically and dynamically change the slew rate corresponding to the change rate and amplitude of the input signal. In this operational amplifier, when voltage (Vin) of the input signal is high, or when it changes drastically, at the time the voltage difference between... Agent: Texas Instruments Incorporated

20070273443 - Operational amplifier circuit: An operational amplifier circuit has a differential input circuit including a first transistor, which receives a first input signal and generates a first voltage, and a second transistor, which receives a second input signal and generates a second voltage. An output stage circuit includes a third transistor responsive to the... Agent: Arent Fox LLP

20070273444 - Techniques for enabling a 10bt active output impedance line driver using a low power supply: A line driver for generating 10 BT signals is disclosed. Digital symbols to be transmitted via a 10 BT Ethernet line are converted by a digital-to-analog converter into a corresponding analog voltage signal, which is fed into an active output impedance line driver. The digital-to-analog converter also receives a reference... Agent: Sterne, Kessler, Goldstein & Fox P.l.l.c.

20070273445 - Millimeter-wave cascode amplifier gain boosting technique: Disclosed is a gain boosting technique for use with millimeter-wave cascode amplifiers. The exemplary technique may be implemented using a 0.18 μm SiGe process (FT=140 GHz). It has also been shown that the technique is effective for CMOS processes with comparable FT. An exemplary gain-enhanced cascode stage was measured to... Agent: Law Offices Of Kenneth W. Float

20070273446 - Automatic input-gain control circuit and method thereof: An automatic input-gain control circuit of an audio amplifier and a method thereof are provided. If an acoustic signal exceeds a dynamic range, a gain of the acoustic signal can be automatically attenuated based on a pre-set limit level to minimize a distortion of the acoustic signal caused by clipping... Agent: Roylance, Abrams, Berdo & Goodman, L.L.P.

20070273447 - Bias circuit for power amplifier having a low degradation in distortion characteristics: A combined bias circuit in which a voltage drive bias circuit and a current drive bias circuit are provided in parallel with each other has a configuration in which a linearizer including a first resistor is connected between an amplifying transistor and a second resistor. This configuration ensures that even... Agent: Leydig Voit & Mayer, Ltd

20070273448 - Output power control of an rf amplifier: Precision and reliability of a current limited mode output power control of an RF amplifier is enhanced by sensing the base current of the current controlled output power transistor. The base current is compared to a control current that is normalized by scaling it as a function of the current... Agent: Allen, Dyer, Doppelt, Milbrath & Gilchrist P.A.

20070273449 - Power amplifier with stabilising network: A power amplifier circuit comprising a transistor for receiving a signal to be amplified at an input and for outputting an amplified signal at an output; a modulated power supply connected to the transistor output; and a resistive element connected at the transistor output such that a low impedance is... Agent: Demont & Breyer, LLC

20070268069 - Apparatus and method for controlling temperature of electronic apparatus: In an embodiment of this invention, if a state, in which duty ratio of a PWM signal is kept equal to or greater than a predetermined value, has been maintained for a first time period, the duty ratio of the PWM signal of a digital power amplifier is adjusted downward.... Agent: Birch Stewart Kolasch & Birch

20070268070 - Power amplifier using transmission line transformer: Disclosed herein is a power amplifier which is used in a wireless communication system and is capable of improving efficiency in an entire output power range and extending the dynamic range without additional switches, by including a drive amplification unit and a power amplification unit, connecting the drive amplification and... Agent: Oliff & Berridge, PLC

20070268071 - High efficiency switch-mode power amplifier: A switch mode power amplifier includes a transistor responsive to input signals above 1.0 GHz and which includes one terminal coupled to ground and another terminal conductively coupled to a power source. A resonant circuit coupled the second terminal to an output with a resistive load coupled across the output... Agent: Myers Bigel Sibley & Sajovec

20070268072 - Low return loss resistive feedback amplifier: Embodiments related to resistive feedback amplifiers are presented herein.... Agent: Lee & Hayes, PLLC C/o Portfolioip

20070268073 - Electronic device: An electronic device includes: a plurality of RF power amplifiers; and an impedance converting circuit. The RF power amplifiers amplify RF signals having different frequencies. The impedance converting circuit receives RF signals output from output terminals of the respective RF power amplifiers at a plurality of input terminals disposed to... Agent: Mcdermott Will & Emery LLP

20070268074 - Dynamically biased amplifier: The present invention provides dynamic biasing of transistor in an amplifier (1) comprising at least two interconnected transistor (10, 20) provided for processing an input signal. Once the input signal is applied to a driver transistor (10), a DC current signal of the output electrode (16) of this transistor (10)... Agent: Nixon & Vanderhye, PC

20070262815 - Electronic signal generator with modulated cyclic ratio, compensated for variations in its power supply voltage: A generator capable of supplying one or more output signals with a modulated cyclic ratio includes one or more formatting circuits each processing one input signal and one or more class D amplifiers powered with a power supply voltage and being driven by a corresponding one of the formatting circuits.... Agent: Gardere Wynne Sewell LLP Intellectual Property Section

20070262816 - Distortion compensation circuit: There is provided a distortion compensation circuit that can compensate for the nonlinearity of an amplifier having the characteristic that the gain is reduced and the phase is delayed with an increase in input power. An inductor 112 is connected in series with a diode 105 of a distortion compensation... Agent: Birch Stewart Kolasch & Birch

20070262819 - Automatic gain control for mobile microphone: An automatic gain control unit controls the gain applied to an input signal produced by a microphone subject to ambient noise. The automatic gain control circuit continually monitors the signal level of said input signal. A first gain control circuit decreases the gain applied to the input signal in increments... Agent: Marks & Clerk

20070262817 - Dynamic lna switch points based on channel conditions: Techniques for operating a receiver to linearity performance and higher receive signal to noise ratio are described. The receiver includes one or more circuit blocks, e.g., a low noise amplifier (LNA), having discrete gain states. The gain states are selected based on switch points, with each switch point indicating a... Agent: Qualcomm Incorporated

20070262818 - Variable gain amplifier with gain adjusting circuit: A variable gain amplifier includes an amplifying circuit and a gain adjusting circuit including the following circuits. A linear exponential transforming circuit transforms a linear controlling signal to output an exponential controlling signal. A voltage buffer circuit is coupled with the linear exponential transforming circuit to receive the exponential controlling... Agent: Birch Stewart Kolasch & Birch

20070262820 - Amplifier thermal management: A thermally regulated amplifier system includes an amplifier unit, a temperature-sensing unit and a controller. The amplifier unit includes a power amplifier that has an adjustable gain function. The controller receives temperature readings from the temperature-sensing unit, computes the gain G(n) of the amplifier unit, and provides the computed gain... Agent: O'shea, Getz & Kosakowski, P.C.

20070262821 - Front-end sensitivity booster: The invention relates to a method for increasing the sensitivity of a chain of amplifiers that comprises the steps of amplifying a signal by means of a first amplifier with a gain factor A1=A1,m*ΔA1, where A1,m denotes a constant gain factor and ΔA1 denotes a gain factor variation with 1≦ΔA1,min≦ΔA1≦ΔA1,max,... Agent: Nxp, B.v. Nxp Intellectual Property Department

20070257732 - Circuits and methods for amplifying signals: The present invention discloses a bus pumping compensation for a pulse modulation circuit such as class D modulators. The compensation according to the present invention provides a compensation current controlled by the output voltage, with the compensation characteristics matching the reverse current for improving circuit efficiency. Embodiments of the present... Agent: Blakely Sokoloff Taylor & Zafman

20070257733 - Amplifier system with current-mode servo feedback: An amplifier apparatus including differential inputs disposed to receive a first and second input signal, a primary differential amplifier having inverting and non-inverting input nodes receiving the first and second input signal through respective first and second impedance elements and providing a main output signal, feedback circuitry disposed to sample... Agent: Mark S. Leonardo, Esq. Brown Rudnick Berlack Israels LLP

20070257734 - Balanced output circuit and electronic apparatus utilising the same: In a balanced output circuit, an input signal inputted thereto is provided as a first output signal thereof on one hand, and on the other hand the input signal is inputted to an inverting amplification circuit and is compared with a comparison voltage before the signal is outputted as a... Agent: Rohm Co., Ltd. C/o Keating & Bennett, LLP

20070252644 - Audio power amplifier ic and audio system provided with the same: An audio power amplifier IC which is capable of suppressing degradation in sound quality resulting from the frequency of a reference clock, and an audio system provided with the audio power amplifier IC are provided. The audio power amplifier IC includes a clock generation circuit (10) generating an internal clock,... Agent: Fish & Richardson P.C.

20070252645 - Amplifier circuit of btl system: An amplifier circuit of a BTL system is disclosed, which comprises a first operational amplifier which outputs an output signal having a same phase as an input signal input to a signal input terminal, a second operational amplifier which outputs an output signal having an opposite phase to the input... Agent: Oblon, Spivak, Mcclelland, Maier & Neustadt, P.C.

20070252646 - Adaptive bias current circuit and method for amplifiers: An adaptive bias method and circuits for amplifiers that provide a substantial current boost based at least partly upon a sensed input power of an amplifier circuit. Methods and circuits of the invention provide an additional bias current based upon the sensed input power. Circuits of the invention may be... Agent: Greer, Burns & Crain

20070252647 - Operational amplifier: An operational amplifier includes: a differential amplifier circuit configured to receive an inverting input voltage (VIN−) and a non-inverting input voltage (VIN+); and an auxiliary circuit for improving a slew rate of an output voltage of the differential amplifier circuit, wherein when a voltage difference between the inverting input voltage... Agent: Morgan Lewis & Bockius LLP

20070252648 - Operational amplifier: An operational amplifier including a first current mirror, a second current mirror, and a differential pair of transistors. The differential pair of transistors are configured to receive two inputs to direct current through the first current mirror and the second current mirror. The first current mirror provides a first current... Agent: Dicke, Billig & Czaja

20070252649 - Amplifier: In a constant amplitude wave-combining type amplifier for splitting a single input signal into two parts by a distributor 1, amplifying the split signal parts by first and second amplifiers 3a, 3b and then combining output signals amplified thereby, the amplifiers 3a, 3b comprise at least two amplifier elements accommodated... Agent: Ostrolenk Faber Gerb & Soffen

20070252650 - Semiconductor amplifier: A first power source 11 for supplying a bias voltage to a gate electrode G of a field effect transistor 13, which amplifies high-frequency signals, and a second power source 15 for supplying a bias voltage to a drain electrode D of the field effect transistor 13 are provided. The... Agent: Oblon, Spivak, Mcclelland, Maier & Neustadt, P.C.

20070252651 - Power amplifier with a output matching network: Provided herein is a power amplifier having a multiple stage power amplifier section and an output matching network section. The multiple stage power amplifier section can include multiple power amplifier stages with interstage matching circuits located therebetween. The output matching network can be configured to match the multiple stage power... Agent: Orrick, Herrington & Sutcliffe, LLPIPProsecution Department

20070252652 - Dual op amp ic with single low noise op amp configuration: A multiple op amp IC with a single low noise op amp configuration comprises at least two op amp circuits fabricated on a common substrate. The IC can be configured such that the multiple op amps are connected in parallel to form a single op amp having output drive and... Agent: Koppel, Patrick & Heybl