Amplifiers inventions 05/06

20060109049 - Low noise audio amplifier: An amplifier circuit performs audio signal processing and other signal processing by using a noise reduction feedback network. The noise reduction feedback network turns on automatically when output signals are in or near voltage saturation state. The network provides feedback signals to the input terminals of the amplifier's control stage...

20060109050 - Apparatus for removing dc offset and amplifying signal with variable gain simutaneously:

20060109051 - Gain adjustment method, gain adjustment circuit, and optical disc device having same gain adjustment circuit: A gain adjustment circuit includes a gain varying device for varying the gain of an input signal; and a detection device for detecting a variable output signal of the gain varying device, wherein the detection output signal of the detection device is fed back to the gain varying device....

20060109052 - Adaptive predistortion for a transmit system: Systems, methods, and devices relating to the provision of deliberate predistortion to an input signal to compensate for distortions introduced by an amplifier subsystem. An input signal is received by a predistortion subsystem which applies deliberate predistortions to the input signal to arrive at a predistorted signal. The predistorted signal...

20060109053 - Series-type doherty amplifier without hybrid coupler: Provided is a series type Doherty amplifier which includes a first power amplifier and a second power amplifier using a plurality of transformers. The first power amplifier and the second power amplifier are connected in series. The second power amplifier and a first transformer are connected in series. A first...

20060109054 - Method and apparatus for limiting power amplifier voltage excursions: A power amplifier circuit includes a circuit topology with first and second switching elements. The first and second switching elements have a closed state and an open state, wherein current flows between the switching elements when they are both in the closed state. The voltage across the first and second...

20060109055 - Low noise op amp: An analog circuit for processing analog signals in an integrated circuit comprising a number of metal oxide semiconductor transistor devices. The circuit includes a first transistor device having a thin oxide thickness, and a second transistor device having a thicker oxide thickness. A voltage pulse protection is arranged to maintain...

20060109056 - Class ab cmos amplifiers: A class AB output stage of a CMOS amplifier has a level-shifting voltage follower constituted by a level-shifting transistor and a current source. A bias circuit replicates the level-shifting voltage follower in a feedback arrangement to produce a variable bias voltage for the current source of both the main and...

20060109057 - Amplifier circuit and light receiving apparatus: An amplifier 11 to which transistors 13 and 14 functioning as variable resistors are connected in parallel is used. A burst signal is received by a light receiving element 10 and the received signal is converted into an input current signal Iin. The input current signal Iin is converted in...

20060103458 - On-the-fly introduction of inter-channel delay in a pulse-width-modulation amplifier: A multiple-channel audio processor (10) and an associated plurality of power stages (22) in an audio system are disclosed. The audio processor (10) includes a plurality of audio amplifier channels (22), each of which includes a pulse-code-modulation (PCM) to pulse-width-modulation (PWM) conversion function (25), which generates PWM signals for application...

20060103459 - Pulse amplitude modulation (pam) method and circuit for improving the performance of a d-class audio amplifier: The present invention provides a PAM (Pulse Amplitude Modulation) method and circuit for improving the performance of a D-class audio amplifier. The D-class audio amplifier is inputted with a PWM signal and designed to have a dead time function for time delay. In order to decrease the distortion of the...

20060103460 - System and method for envelope modulation: A power control system for a satellite receiving radio-frequency signals includes a digital processor and a traveling wave tube amplifier system and corresponding traveling wave tube. An anode voltage of the traveling wave tube amplifier system is used to modulate or saturate the current of the electron beam of the...

20060103461 - System, method and apparatus for providing ground separation between different environments: In one embodiment, ground separation is provided between first and second grounded environments by configuring first and second op-amps of the second grounded environment as buffers, configuring a third op-amp of the second grounded environment to output a difference of its inputs, and coupling the inputs of the third op-amp...

20060103462 - Method and apparatus for opening a feedback loop: Circuits, methods, and systems are provided for opening a primary feedback loop in a transmitter. An auxiliary feedback loop can be closed when the primary feedback loop is opened, and a controller can match a gain of the primary feedback loop to another gain in the transmitter....

20060103463 - Programmable gain current amplifier: A programmable gain current amplifier is provided, including a transistor pair, a plurality of differential pairs, and a control device. The transistor pair receives an input current. Each differential pairs connecting with each other in parallel is connected to the transistor pair to form a differential current mirror for amplifying...

20060103464 - Differential amplifier circuit capable of reducing current consumption: An integrated circuit device includes a differential amplifier, an output driver and a control circuit. The differential amplifier is responsive to a pair of differential input signals and may include a pull-down current source responsive to a pair of bias signals. The output driver has a pull-up path and pull-down...

20060103465 - Automatic gain control and tuned low noise amplifier for process-independent gain systems: A tuned low-noise amplifier is disclosed. A device in accordance with the present invention comprises a first current source, a second current source, a comparator, coupled to the first current source and the second current source, for providing a control signal, and a third current source, receiving the control signal...

20060103466 - High efficiency doherty amplifier with a segmented main amplifier: A Doherty amplifier that includes a main amplifier device and an auxiliary amplifier device. The main amplifier device includes a plurality of independently controllable amplifier segments. The system further includes a coupler for coupling an input signal to each of the main amplifier device and the auxiliary amplifier device. The...

20060103467 - Re-configurable amplifier protection apparatus and method: The present invention is directed to an amplifier, which is able to re-configure its internal protection circuits based on an output signal level. This allows the amplifier to apply the best protection level to the present operational condition. The protection level or threshold for protecting the amplifier is dynamically adjusted...

20060103468 - Single-ended input to differential output low noise amplifier with a cascode topology: A single-ended input to differential output LNA with a cascode topology of the present invention overcomes a much greater consumption of current and area for the single-ended input to differential output LNA of the prior art. The LNA needs to supply an operating bias for each transistor. The LNA has...

20060103469 - Filter circuit providing low distortion and enhanced flexibility to obtain variable gain amplification: A low distortion filter circuit implementing variable gain amplification (VGA). An aspect of the present invention increases the degrees of freedom (number of components which can be independently programmed/changed to corresponding desired values) to achieve a desired combination of D.C. gain and filter characteristics (e.g., corner frequency, Q-factor, notch frequency,...

20060103470 - Power amplifier module: A semiconductor chip is wired with a bonding wire on a conductor pattern formed on a substrate, the bonding wire is connected to a bonding position at a midpoint of a distributed constant line formed by the conductor pattern and divides the line into a first inductor and a second...

20060103472 - Light receiving amplification circuit: A light receiving amplification circuit according to the present invention includes: a light receiving element (101); an amplification circuit which amplifies a photoelectric current generated by the light receiving element and outputs from an amplification stage for external output (117) and a plurality of amplification stages for feedback (109 and...

20060103471 - Preamplifier: A preamplifier includes a negative-feedback amplifier circuit that converts a current signal from a photodetector into a voltage signal; and a conversion-gain control circuit that simultaneously controls a resistance value of a feedback resistor portion of the negative-feedback amplifier circuit and a resistance value of a load resistor portion of...

20060097782 - Amplifier with low pass filter feedback: An amplifier is described which amplifies an input signal according to a defined amplification factor, and which generates an output signal. To reduce an offset fraction of the output signal the amplifier comprises a feedback path which has lowpass characteristics and which returns the output signal in a lowpass-filtered state...

20060097783 - Amplifier: There is provided an amplifier for combining outputs of a plurality of amplifying circuits to generate an amplifier output. The amplifier includes a first amplifying circuit for operating a first amplifying device in class-AB, wherein the first amplifying circuit is one among the plurality of the amplifying circuits; a second...

20060097784 - Amplifier apparatus: An amplifier apparatus includes: (a) an integrator having an input for receiving an input signal, and integrating the input signal to present an integrated signal; (b) a first comparer coupled with the integrator for comparing the integrated signal with a varying reference signal to produce an output signal; and (c)...

20060097785 - Btl amplifier: In a BTL amplifier of the present invention, between first and third transistor parts (10, 11) which are laterally adjacent, directions of semiconductor regions (102, 104, 106) are parallel. Between the first and second transistor parts (10, 12) and the third and fourth transistor parts (12, 13), each which are...

20060097786 - Low noise and high gain low noise amplifier: A high-gain and low-noise low noise amplifier (LNA) includes a differential amplifier, a pre-amplifier and an impedance matching network. The differential amplifier includes a first input end and a second input end coupled to a grounded impedance. The pre-amplifier includes an input end and an output end. The impedance matching...

20060097787 - Gain adjusting and circuit arrangement: The present invention relates to a method and circuit arrangement for adjusting a gain, wherein said circuit arrangement comprises at least a first output branch connected to a first load and a second output branch connected to a second load. The gain control function is realized based on a current...

20060097788 - Transconductance amplifier having common mode feedback circuit and method of operating the transconductance amplifier: A complementary transconductance amplifier having a common mode feedback circuit includes a first-type transconductor, a second-type transconductor and a common mode feedback circuit. The first-type transconductor generates a first differential output signal pair in response to a differential input signal pair under the control of a first control signal. The...

20060097789 - Amplifier circuit: An amplifier circuit includes: an amplifier with a CMOS field effect transistor; and a frequency response control circuit that attenuates low frequency portions of a signal output by the amplifier....

20060097790 - On-chip temperature compensation circuit for an electronic device: A general purpose Darlington pair amplifier circuit, configured in accordance with a preferred embodiment of the invention, utilizes GaAs heterojunction bipolar transistor technology. The amplifier circuit incorporates a temperature compensation circuit at the input stage that controls the total current drawn by the transistors such that the total current is...

20060097791 - Low offset rail-to-rail operational amplifier: An operational amplifier with a first stage differential input circuit having low aspect ratio devices of size chosen to achieve a low offset voltage, and an output stage having high aspect ratio devices able to operate at higher frequencies than the input stage, provides an amplifier with low static offset...

20060097792 - Variable gain amplifier: A variable gain amplifier (VGA) having stable input impedance matching and a stable noise figure in spite of a variation of an amplification gain is provided. In an embodiment of the VGA, a first stage of a cascode amplification unit has a fixed impedance regardless of a change of an...

20060091945 - Switching power amplifier and method for amplifying a digital input signal: Switching power amplifier includes a first signal path having a pulse modulator for modulating an input signal, and a switching power unit for amplifying the modulated signal to generate an amplified output signal; a second signal path for generating a reference signal in response to the input signal; and a...

20060091946 - Wideband feed forward linear power amplifier: A circuit is provided, having a feed forward linear power amplifier configured with two or more error correction loops (225-235, 255-265). Each of the error correction loops includes a band pass filter (237, 257). Each of the band pass filters (237, 257) is tuned to a different frequency range. A...

20060091947 - Amplifier circuit: The present invention provides an amplifier circuit comprising a differential amplifier and a negative feedback loop circuit, in which a positive feedback loop circuit having a gain smaller than a gain of the negative feedback loop circuit is formed inside the negative feedback loop circuit....

20060091948 - Method and system for low noise amplifier (lna) gain adjustment through narrowband received signal strength indicator (nrssi): Methods and systems for processing a plurality of signals are disclosed herein. Aspects of the method may comprise amplifying an input signal. The amplified input signal may be bandpass filtered. Amplification of the input signal may be adjusted based on only narrowband received signal strength indication of the bandpass filtered...

20060091950 - Amplification device: An amplifier apparatus in which a signal is amplified by an amplifier and distortion produced by the amplifier is compensated for, that can continue to operate even in cases where the amplitude of a distortion component contained in the amplified signal after distortion compensation has become large. Distortion component amplitude...

20060091949 - Signal correction by predistortion: A digital predistorter comprises a module (J) for producing a counteracting signal Vm1 for combination with the input signal of a power amplifier to correct the output of the amplifier for distorting memory effects within the amplifier. The module (J) produces the counteracting signal Vm1 by convolving (see FIG. 6)...

20060091952 - High-swing folded cascode having a novel gain-boost amplifier: A circuit topology for gain boosted high-swing folded cascode has been improved to maximize the available dynamic range in applications having low supply voltage requirements. The circuit includes an improved gain boost amplifier that maximizes the available dynamic range for applications having low supply voltage requirements. The improved gain boosting...

20060091951 - Integrated circuit amplifier device and method using fet tunneling gate current: An integrated circuit amplifier includes, in an exemplary embodiment, a first field effect transistor (FET) device configured as a source follower and a second FET device configured as a tunneling gate FET, the tunneling gate FET coupled to the source follower. The tunneling gate FET is further configured so as...

20060091953 - Class b amplifier with process variation independent deadband: A class B amplifier circuit produces a deadband that is independent of semiconductor process variations and creates a positive voltage when a differential input voltage is non-zero. A differential input amplifier couples differential currents representing the differential input voltage to a logarithmic compression circuit which in turn creates an output...

20060091954 - Method and system for common mode feedback circuitry for rf buffers: For a high frequency buffer, a high frequency output path may be isolated from a low frequency feedback path using a common mode feedback loop. The common mode feedback loop may be utilized to adjust an output DC level. The common mode feedback loop may comprise a first differential amplifier...

20060091955 - Circuits and methods for improving slew rate of differential amplifiers: Circuits and methods are provided for providing high speed operational amplifiers and, in particular, operational amplifiers having frequency compensation circuits that provide improved slew rates with low power dissipation when configured with feedback. Frequency compensation schemes are provided to enable dynamic configuration of frequency compensation circuits implementing miller compensation whereby...

20060091956 - Amplifying a signal using a control modulator that provides a bias resistance: According to one embodiment of the present invention, an amplifier includes an amplifying transistor coupled to a ground and operable to amplify a received signal. One or more bias components provide a bias resistance for the amplifying transistor. The one or more bias components include a control modulator coupled in...

20060091957 - Method and system for low noise amplifier (lna) and power amplifier (pa) gain control: Methods and systems for processing signals are disclosed herein. In one aspect of the invention a circuit for processing signals may comprise a triple well (TW) NMOS transistor coupled to an amplifier core. The TW NMOS transistor may track process and temperature variations (PVT) of at least one NMOS transistor...

20060091958 - 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...

20060091959 - Low noise amplifier with low noise, high isolation bias circuit: A low noise amplifier and method for amplifying an input signal uses a high impedance electrical element having both inductance and capacitance connected between an output transistor and a bias circuit to provide noise isolation between the bias circuit and the output transistor. The noise isolation provided by the high...

20060091960 - Current limit circuit for power amplifiers: According to one embodiment of the invention, a circuit arrangement includes a regulator circuit. The circuit arrangement further includes a current limit circuit coupled to the regulator circuit. The circuit arrangement further includes a power amplifier coupled to the regulator circuit, where the power amplifier is configured to draw a...

20060091961 - Overcurrent protection circuit with fast current limiting control: An overcurrent protection circuit for a power transistor includes a transconductance amplifier and a bias current circuit. The transconductance amplifier receives a first signal indicative of the magnitude of the load current conducted by the power transistor and a reference voltage and provides a second signal for controlling the load...

20060091962 - Amplifier circuit having improved linearity and frequency band using multiple gated transistor: Disclosed herein is an amplifier circuit having improved linearity and frequency band using a MGTR. The amplifier circuit comprises an amplification unit including a main transistor and an auxiliary transistor, an attenuation unit including inductors respectively connected to the source of the main transistor and the source of the auxiliary...