Amplifiers inventions 10/06

20060238241 - Monolithic class d amplifier: A monolithic 1.75 is mounted in a speaker cabinet 1.71 to drive the voice coil 1.74 of the speaker 1.70. The monolithic integrated circuit may be a class D amplifier 1.10, and is at least a half-bridge or full bridge power MOSFET device. Structures and process for forming the mos...

20060238242 - Differential amplifier and data driver for display: Disclosed is a differential amplifier comprising first and second terminals for receiving signals; a third terminal for outputting a signal; first and second differential pairs, each having an input pair and an output pair, said first and second differential pairs being supplied with currents from current sources associated therewith, respectively;...

20060238243 - Differential amplifier, data driver and display: Disclosed is a differential amplifier which comprises first and second terminals for receiving signals; a third terminal for outputting a signal; first and second differential pairs, each having an input pair and an output pair, said first and second differential pairs being supplied with currents from associated current sources, respectively;...

20060238244 - Power amplifier: Improved methods and systems for amplifying a signal are provided. Specifically, systems and methods for amplifying a signal through a lossy switch element tied to two or more voltage sources are provided. In the preferred embodiment, envelope information from the signal is used to smoothly transition between the two or...

20060238245 - Rf amplifier employing active load linearization: A power amplifier system for high efficiency signal amplification of digitally modulated carrier signal or multi-carrier signals is disclosed. The linearity of the amplifier is improved by providing dynamic load line adjustments through implementation of suitably defined transfer functions employing dynamic control of operational aspects of active devices in the...

20060238246 - Distortion compensating amplifier: In a distortion compensating amplifier that compensates for distortion occurring in main amplifiers, a first amplifying unit amplifies, with a first main amplifier, a first signal consisting of a main signal to be amplified and detects distortion occurring in the first main amplifier, a distortion adjusting unit subjects the distortion...

20060238247 - Circuit for preventing output of pop noise: Disclosed is a circuit for preventing an output of a pop noise, which occurs from an audio amplifier when a power switch of an electronic device loading the amplifier is turned on/off. The circuit may comprises an analog switch for switching an electrical connection between an audio amplifier and a...

20060238251 - Analog circuit and display device and electronic device: The invention provides an analog circuit that decreases an effect of variation of a transistor. By flowing a bias current in a compensation operation, a voltage between the gate and source of the transistor to be compensated is held in a capacitor. In a normal operation, the voltage stored in...

20060238249 - Control circuit for operational amplifier and method thereof: A control circuit for an operational amplifier and a method thereof are provided to dynamically modulate the operational amplifier for strong driving capability and power saving. The control circuit comprises a bias unit coupled to the operational amplifier and a control unit coupled to the bias unit. The bias unit...

20060238248 - Differential inductor-based low noise amplifier: An embodiment of the present invention is a low noise amplifier using differential inductors. An input matching circuit having first and second differential inductors matches an input resistance at an input having input terminals. A differential amplifier circuit converts the input voltage a current. An output circuit provides an output...

20060238250 - Method for dynamic insertion loss control for 10/100/1000 mhz ethernet signaling: The present invention provides for dynamic insertion loss control for a 10/100/1000 megahertz Ethernet power on differential cable pairs. A power feed circuit supplies power to a network attached device (PD). An insertion loss control circuit limits power loss in a coupled power feed circuit. The insertion loss control circuit...

20060238252 - Network device with power potential rectifier: In a network device, a power potential rectifier is adapted to conductively couple a network connector to an integrated circuit that rectifies and passes a power signal and data signal received from the network connector. The power potential rectifier regulates a received power and/or data signal to ensure proper signal...

20060238254 - Input system for a variable gain amplifier having class-ab transconductance stages: An amplifier has an input terminal to receive an input signal. The amplifier includes a first gain stage comprising a pair of input transistors and a second gain stage to drive an output stage. The output stage provides inverting and non-inverting differential output signals on inverting and non-inverting output nodes....

20060238253 - Sensitivity switchable detection circuit and method: A sensitivity switchable detection circuit includes a high gain circuit for outputting a first signal, a low gain circuit for outputting a second signal, and an output switching circuit for switching between the first signal and the second signal. When the first signal is smaller than a lower limit, the...

20060238255 - Automatic gain control with three states of operation: A method and apparatus for an automatic gain control (AGC) loop that utilizes freezing and unfreezing states. A freezing process moves the AGC into a TRANSITION state from a NORMAL state, based on net change of VGA gain control codes over a monitoring time window. The freezing process then moves...

20060238256 - Gigabit ethernet transceiver with analog front end: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators. Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal. By isolating the switches from the signal path linearity of the PGA can be...

20060238257 - Control of transmission power in a mobile station: An apparatus adapted to control transmission power in a mobile station comprises a power amplifier adapted to amplify a radio signal with a gain characteristic corresponding to a computed transmission level, and an automatic gain control unit adapted to generate an automatic gain control signal to control a gain of...

20060238258 - Ultracapacitor audio amplifier: An amplifier that employs ultracapacitors to accommodate the peak power needs of an electrical system, such as car audio system. The amplifier operates off of a primary power source for average signal power levels and then uses the ultracapacitors when operating at peak power levels. As such, the amplifier can...

20060232331 - Segmented chopping amplifier: A chopping amplifier and method for chopping an input signal are disclosed. The chopping amplifier and method utilize at least two chopping amplifier stages. A chopping operation of an input signal is segmented across two or more chopping amplifier stages, and the two or more chopping amplifier stages are responsive...

20060232332 - Adaptive predistortion linearized amplifier system employing selective sampling: An adaptive predistortion linearized amplifier system employing selective sampling is disclosed. Two selective sampling methods of identifying valid measurements using information from the input signal are disclosed. The selective sampling process improves the convergence properties of tuning algorithms based on minimizing the gain error variance. It also reduces the number...

20060232333 - Device for connecting electric household appliances to an electric power main: A device for connecting electric household appliances to an electric power main has an input line connectable to a terminal of an electric power main; and at least one output terminal. The connecting device also has a detection stage for detecting electric power drawn by the input line; and a...

20060232334 - Analogue multiplier: An analogue multiplier circuit has an input coefficient voltage dependent adjustment of its frequency response. The multiplier contains a multiplier cell (MC) with an RF input (Vin+, Vin−) and a coefficient signal input (Vcoeff+, Vcoeff−), one or more capacitors (Cp1, Cp2) as peaking capacitors, which one contact connects to the...

20060232335 - Method for single-end offset compensation of an operational amplifier: The present invention provides a method for single-end compensation of an operational amplifier, which comprises: designing an operational amplifier having a single-end offset style, preparing a common-mode circuit, a switch circuit, a comparator, a digital circuit and a compensation circuits. When a single-end offset voltage of the operational amplifier is...

20060232336 - Variable-gain differential amplifier: A variable-gain amplifier with high input impedance includes positive and negative inputs, positive and negative outputs, first and second differential circuits and first, second and third impedances. The impedances form an impedance bridge between the outputs. The first and second differential circuits each have one input coupled to one of...

20060232337 - Fully differential amplifier device with output-common-mode feedback and control method thereof: A fully differential amplifier device includes a first input and a second input, a first output and a second output, and a differential input stage, provided with a first input transistor and a second input transistor. The first input and the first output and the second input and the second...

20060232338 - Amplifier system having compensated amplification variation: An amplifier system is provided for amplifying an input signal to provide an amplified output signal, amplifying an amplified input signal to provide a further amplified output signal, and phase delay compensating variations of the amplifications of the amplified output signal and the further amplified output signal for providing the...

20060232339 - Electronic amplifier with signal gain dependent bias: An apparatus having an electronic amplifier with signal gain dependent bias. The electronic apparatus includes the amplifier and a bias state control circuit. The electronic amplifier has a signal gain and a bias state. The signal gain is adjustable to either of at least two different signal gain settings, and...

20060232340 - Current mirror with low headroom requirement: A current mirror circuit includes a current input node for receiving an input current, an upper, cascoded current mirror, a lower current mirror, and a biasing means. In a FET implementation, the upper mirror includes first and second cascoded FETs which are connected together at the current input node, and...

20060232341 - Radio frequency power amplifier: There are provided an RF power amplifier transistor (2), a bias supply circuit (51) which supplies a bias current to the base of the RF power amplifier transistor and a bias control circuit (52) connected between the base of the RF power amplifier transistor and bias supply circuit, and the...

20060232342 - 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....

20060226898 - Offset correction circuit for voltage-controlled current source: Novel circuitry and methodology are provided for correcting the offset associated with a voltage-controlled current source. An offset correction circuit is coupled to the current source to prevent the output current produced by the current source from deviating from a desired level. The current source may include a transconductance amplifier...

20060226899 - Operational amplifier, line driver, and liquid crystal display device: An operational amplifier capable of offset cancel in a shorter period, as well as a line driver capable of shortening one horizontal period and a liquid crystal display device are provided. In the operational amplifier of the invention, a time necessary for feed back control can be shortened than usual...

20060226900 - Demodulation and regulation concept for ir receivers: A method and circuit for amplifying and demodulating amplitude-modulated signals is disclosed that amplifies a primary signal into an amplified signal, bandpass filters the amplified signal into a filtered signal, compares the filtered signal with a regulation threshold and regulates the gain of the primary signal such that peak values...

20060226901 - Low phase shift implementation of the baseband circuitry of a cartesian feedback loop: A circuit is provided that includes a Cartesian feedback loop. The Cartesian feedback loop includes one or more operational amplifiers. At least one of the operational amplifiers includes two or more cascaded amplifier stages and one or more bypass amplifier stages. The bypass amplifier stages are connected in parallel with...

20060226902 - Amplifying a signal using a current shared power amplifier: A power amplifier includes amplifier stages. An amplifier stage includes a transistor, and at least one amplifier stage comprises a driver stage. The amplifier stages include a first amplifier stage having a first transistor and associated with a first output power, and a second amplifier stage having a second transistor...

20060226903 - Method for signal processing and a transmitting device with digital predistortion, in particular for mobile radio: A transmitting device with digital predistortion is disclosed. The device produces a power word derived from an amplitude component of a digital modulation signal and a desired output power. The power word is compared with a limit value, and depending on the result, one pair of predistortion coefficients is selected...

20060226904 - Minimum on time, dual supply class d amplifiers with ground speaker returns and methods of class d amplification: Class D amplifiers and methods of amplification wherein a load is periodically coupled to a positive power supply connection through a first switch or a negative power supply connection through a second switch for a period responsive to an input signal. A third switch couples the load to a circuit...

20060226905 - Stacked rf power amplifier: A method and apparatus provides techniques for electrically isolating switching devices in a stacked RF power amplifier, which prevents the switching devices from being subjected to high breakdown voltages. The isolation provided allows the power amplifier to be implemented on an integrated circuit....

20060226906 - Differential amplifier and method for generating computer simulation model thereof: A differential amplifier and a method for generating a computer simulation model thereof are disclosed. The device is thermally stable through adoption of a ballast resistor to a differential structure of a unit transistor pair, such that the differential amplifier prevents heat effect phenomena, such as performance deterioration and device...

20060226907 - Vector modulator having attenuators with continuous input steering: Variable attenuation systems having continuous input steering may be used to implement vector or quadrature modulators and vector multipliers. Discrete implementations of attenuators with continuous input steering may have two outputs which may be cross-connected to provide four-quadrant operation. A symmetrically driven center tap may provide improved zero-point accuracy....

20060226908 - Differential amplifying method and apparatus operable with a wide range input voltage: A differential amplifying apparatus includes first and second differential transistor pairs of different polarities operated by different constant currents, and first to sixth current mirror circuits. The second, third, fifth, and sixth current mirror circuits are connected to an output terminal. The first, second, and sixth current mirror circuits receive...

20060226909 - Monolithic supply-modulated rf power amplifier and dc-dc power converter ic: Embodiments of RF power amplifiers are disclosed that include switched-mode power amplifiers supplied by synchrnous buck DC-DC converters. The switched-mode power amplifiers can be used to amplify a limited form of an RF input signal and the supply to the switched-mode power amplifier is varied in response to the envelope...

20060226910 - Bias circuit for a wideband amplifier driven with low voltage: An amplifier includes a ground, first and second MOS transistors, a first resistive load and a supply voltage, which are connected in series in this order. A bias circuit provides first and second bias voltages to the gate electrodes of the first and second transistors, respectively. The bias circuit includes...

20060226911 - Linearized bias circuit with adaptation: A linearized bias circuit with adaptation resolves the problem happening to the power amplifier with conventional bias circuit that the DC and AC characteristics of the power amplifier shift or even deteriorate due to a temperature variation. The linearized bias circuit with adaptation has a reference voltage source, a first...

20060226912 - Apparatus and method for limiting voltage surge at amplifier start up: An apparatus for reducing voltage surge while powering up an amplifier device, the amplifier device charging an input capacitance in at least one input line during the powering up, the charging being subject to a time constant established by the input capacitance in cooperation with an input resistance in the...

20060226913 - Circuit for varying gain of preamplifier: A gain switching circuit switches a conversion gain of a preamplifier that is configured with a series circuit formed with a first resistor and a first switching element and a series circuit formed with a second resistor and a second switching element respectively connected in parallel with a feedback resistor....

20060220734 - Method and circuit for input offset correction in an amplifier circuit: A method and circuit for eliminating input voltage offset in an amplifier circuit are provided. An exemplary offset correction circuit is configured with DC restoration to eliminate the DC input voltage offset by suitably providing a correction voltage to correct an input voltage offset during operation of the amplifier circuit,...

20060220735 - Gate driver for class d audio amplifier with adaptive dv/dt control: Provided is a gate driver circuit for a Class D audio amplifier with adaptive dV/dt control. The circuit includes an output switching stage, a gate driver capable of driving the output switching stage with a variable dV/dt; and a mode control circuit for setting an operating mode of the gate...

20060220736 - Low noise amplifier and differential amplifier with variable gain mode: A low noise amplifier (LNA), and more particularly, to a LNA capable of making gain variable is provided. The variable gain LNA comprises a selection unit comprising a first selection cell, a second selection cell, and a third selection cell for selectively transmitting an input signal to an amplification unit...

20060220737 - High q monolithic inductors for use in differential circuits: The present invention provides a differentially driven monolithic inductor circuit having a shield differentially driven by phase shift buffers and a single-ended monolithic inductor circuit having single-ended shields driven by phase shift buffers, both inductor circuit types providing high Quality factor (Q) at operating frequencies in the multi-GHz range and...

20060220738 - Wireless transmitter having multiple programmable gain amplifiers (pgas) with tuned impedance to provide substantially linear magnitude and phase responses: A method and apparatus are provided for enabling a transmitter to have a substantially linear magnitude response and a substantially linear phase response. The transmitter includes first and second programmable gain amplifiers (PGAs). The first PGA is tuned to have a resonant frequency that is less than an operating frequency...

20060220739 - Rf power amplifier circuit and rf transmitter and terminal including it: A RFPA (radio frequency power amplifier) circuit (150) which includes a RFPA (101), a supply voltage source (104), means (155) for applying to the RFPA a gain control bias voltage and a feedback control loop (156) for adjusting a voltage applied to the RFPA, the feedback control loop including a...

20060220740 - Apparatus for current measuring and a resistor: A current measuring apparatus using a resistor comprised of a first resistive element: first electrodes disposed on the two ends of the first resistive element; an insulator arranged on the periphery of the first resistive element; a second resistive element arranged on the periphery of the insulator; and second electrodes...

20060220741 - Cmos class ab folded cascode operational amplifier for high-speed applications: An operational amplifier (1A or 1B) includes a translinear transconductance stage (2B or 2C) receiving an input signal (Vin) of the operational amplifier and operative to produce a first current (ID18) having a square-law relationship to the input signal (Vin) and a folded cascode operational amplifier (3B) including a differential...

20060220742 - Circuit and method for automatic gain control: A system for generating a supply voltage, temperature and process compensated gain control voltage from a digital data word. In particular, the compensated gain voltage control voltage maintains a linear relationship between a change in gain in response to an input gain control voltage for a gain circuit of a...

20060220743 - Variable gain amplifier, mixer and quadrature modulator using the same: A variable gain amplifier includes a voltage-to-current converter for converting the input voltage to a current, a current amplifier for amplifying the current converted by the voltage-to-current converter, a current-to-voltage converter for converting the current amplified by the current amplifier into a voltage, and a controller for controlling an amplification...

20060220744 - Doherty power amplifier with phase compensation: A Doherty power amplifier is provided that includes a main amplifier device and an auxiliary amplifier device. The Doherty power amplifier further includes a phase compensation network. The phase compensation network is configured to maintain a substantially constant phase of one of an output signal from the main amplifier device...

20060220745 - Amplification circuit and control method of amplification circuit: An amplification circuit connected with a lowpass filter, which reduces the time required for compensating the amplification characteristic and starting up at turning on the power supply, and a control method thereof are provided. An amplification circuit 10, which operates in any one of the operation mode of ordinary operation...

20060220747 - Light receiving amplifier circuit and optical pickup device having the same: In a light receiving amplifier circuit, a dummy amplifier has an identical structure with an IV amplifier except that the dummy amplifier is not connected to a light receiving element and includes a capacitor, i.e., a band limiting capacitor. Further, the capacitor is connected between the collector of the grounded-emitter...

20060220746 - Sensing circuit: A sensing circuit capable of detecting very low current pulses of the order of 10's and 100's of micro amps. The sensing circuit comprises a common gate amplification stage capable of amplifying a sensed current, a comparison stage having as an input the amplified sensed current and a feedback stage...

20060220748 - Use of a thick oxide device as a cascode for a thin oxide transconductance device in mosfet technology and its application to a power amplifier design: A power amplifier power amplifier includes a transconductance stage and a cascode stage. The transconductance stage that is operable to receive an input voltage signal and to produce an output current signal. The transconductance stage includes a first Metal Oxide Silicon (MOS) transistor having a first gate oxide thickness and...