Inventors list

Assignees list

Classification tree browser

Top 100 Inventors

Top 100 Assignees


Including signal feedback means

Subclass of:

330 - Amplifiers

330250000 - WITH SEMICONDUCTOR AMPLIFYING DEVICE (E.G., TRANSISTOR)

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
330291000 Including signal feedback means 67
20120176199TRANSIMPEDANCE AMPLIFIER, INTEGRATED CIRCUIT AND SYSTEM - An integrated circuit according to one embodiment includes a first transimpedance amplifier and a second transimpedance amplifier. In the integrated circuit, one of the first transimpedance amplifier and the second transimpedance amplifier is set into an enabled state and the other is set into a disabled state. The first transimpedance amplifier and the second transimpedance amplifier share an input transistor. The first transimpedance amplifier has a first resistor provided between a feedback node thereof and an input node connected to the input transistor. The second transimpedance amplifier has a second resistor provided between a feedback node thereof and the first resistor. A feedback resistor of the second transimpedance amplifier is configured with a series connection of the first resistor and the second resistor.07-12-2012
20130082782Circuit and Power Amplifier - A cascode circuit includes a first transistor and a second transistor. The first transistor and the second transistor are connected to make a cascode. In addition, the circuit has a block capacitance which is connected between a control terminal of the second transistor and a source terminal of the first transistor. In addition, the circuit has a feedback element which is connected between a drain terminal of the second transistor and a control terminal of the first transistor.04-04-2013
20090315624ACTIVE RESISTOR USED IN A FEEDBACK AMPLIFIER PARTICULARLY USEFUL FOR PROXIMITY COMMUNICATION - An active resistor and its use in a negative feedback amplifier allow wide voltage swings on the input and output signals. One embodiment includes parallel pass-gate MOS transistors of opposite conductivity types connected between the input and output nodes. Bootstrapping transistors are connected between the gates of the pass-gate transistors and respective bias voltages. Coupling capacitors are connected between the gates and the output node. Additional coupling capacitors may be connected between the gates and the input node to make the resistor symmetric. In other embodiments, only one pass-gate transistor is used.12-24-2009
20130057350Apparatus and Method for Low Noise Amplification - Embodiments provide an amplifier and a method for using and manufacturing said amplifier that incorporate an impedance matching stage, a feedback circuit, and a gain stage. The impedance matching stage is coupled to the feedback circuit wherein the feedback circuit provides a compensated operating voltage for the impedance matching stage. The output of the impedance matching stage is used to set an input bias voltage for both the impedance matching stage and the gain stage. The output of the impedance matching stage is also used, together with the output of the gain stage, to produce an output of the amplifier.03-07-2013
20130113569CROSS-COUPLED MULTIPATH FEEDFORWARD OPERATIONAL AMPLIFIERS - An operational amplifier can include a plurality of amplifiers connected to form a plurality of amplification paths extending from an input terminal to an output terminal of the operational amplifier. An amplifier in one of the amplification paths can include an intrinsic amplification-transistor capacitance connected between a first amplifier input and a first amplifier output, and a cross-coupling capacitor connected between the first amplifier input and a second amplifier output. A plurality of the amplification paths can include series-connected amplifiers connected in parallel with the cross-coupled amplifier. The cross-coupling capacitor can have a capacitance value selected as a function of the intrinsic capacitance and a gain experienced between the amplifier inputs and outputs. The operational amplifier can include an AC coupling capacitor connected in series with the cross-coupled amplifier. The operational amplifier can be arranged in feedback configuration.05-09-2013
20130063214Quiescent Control Circuit for Providing Control Current for an Amplifier - Disclosed is a Class-AB/B amplifier comprising a first output stage including a first plurality of amplification devices and a second output stage including a second plurality of amplification devices. According to one embodiment, the first output stage operates when the Class-AB/B amplifier is in a quiescent state and the second output stage operates when the Class-AB/B amplifier is in an active state. The Class-AB/B amplifier also comprises a level shifting circuit that adjusts a control voltage of the second output stage, where the level shifting circuit is adapted to activate the second output stage when the Class-AB/B amplifier enters the active state. Embodiments of the Class-AB/B amplifier may include a level shifting circuit that implements either a fixed or signal-dependent level shift, and a quiescent control circuit that substantially eliminates any systematic offset arising from the active feedback circuit inside the replica bias circuit.03-14-2013
20130063213MATRIX DISTRIBUTED POWER AMPLIFIER - Disclosed is a matrix distributed amplifier (DA) having an input transmission line, an intermediate transmission line, and an output transmission line. A first plurality of amplifiers has inputs coupled to and spaced along the input transmission line and has outputs coupled to and spaced along the intermediate transmission line. A second plurality of amplifiers has inputs coupled to and spaced along the intermediate transmission line and has outputs coupled to and spaced along the output transmission line. A termination amplifier has an input coupled to the input transmission line and an output coupled to the intermediate transmission line. In at least one embodiment, a second termination amplifier has an input coupled to the intermediate transmission line and an output coupled to the output transmission line.03-14-2013
20090009255Unilateral feedback power amplifier and method for realizing the same - A unilateral feedback power amplifier utilizes new feedback techniques and devices to make the amplified high-frequency signal unilateral, let the output power, power gain and impedance matching simultaneously accomplish the optimal values, and enhance the stability of the system. In this feedback amplifier, a generalized multi-port feedback circuit is in shunt with the input terminal and the output terminal of the power transistor. This generalized multi-port feedback circuit receives an amplified high-frequency signal and eliminates the reverse admittance of the amplified high-frequency signal to let the admittance value of the output amplified high-frequency signal approach zero so as to be unilateral. Moreover, the generalized multi-port feedback power amplifier differs from the conventional power amplifier of cascaded architecture in that the ground terminal of the power transistor is directly connected to the system ground. Therefore, the heat-radiating problem of the power transistor can be greatly improved.01-08-2009
20090251219Amplifier Arrangement and Signal Generation Method - An amplifier arrangement includes an output amplifier stage (OA) comprising a stage input (SIN), a stage output (SOUT) which is coupled to a signal output (OUT) of the amplifier arrangement, and a capacitive element (CE) which couples the stage output (SOUT) to the stage input (SIN). A driver stage (DR) comprises a driver input (DIN) and a driver output (DOUT) which is coupled to the stage input (SIN) The driver stage (DR) is configured to generate a voltage potential at a driver output (DOUT) depending on an input current at the driver input (DIN) and to provide a charging current to the capacitive element (CE) being higher than the input current.10-08-2009
20110279183Electronic Circuit with a Linear Amplifier Assisted by a Switch-Mode Amplifier - An electronic circuit includes a linear amplifier unit having a first current feedback loop, assisted by a switched-mode amplification unit having a second current feedback loop. The inputs of the two units are connected so that they receive, at the same time, a current setpoint in an operating mode in order to generate a fixed current across a load connected to the output of the units. The first feedback loop includes a first sensor to measure the current in the load, a first subtractor element to subtract the first measured current from the current setpoint, a first controller connected to the output of the first subtractor element and controlling a linear amplifier, which supplies the first output current to the load. The second feedback loop includes a second current sensor to measure a second current supplied to the load, between a connecting node of two switches connected in series to a supply voltage source and an inductor whose output is connected to the load. The second loop further includes a second subtractor element to subtract the second measured current from the current setpoint, a second controller connected to the output of the second subtractor element and controlling a pulse-width modulator that controls the activation of the switches to alternately connect the inductor either to the high potential or to the low potential of the supply voltage source.11-17-2011
20110291763LOW NOISE AMPLIFIER - A method for low noise signal amplification includes modifying a signal by way of a first amplification stage and conveying the modified signal to a second amplification stage. The method continues with comparing an output of the second amplification stage with a signal ground in a low-frequency feedback loop and changing a bias voltage for the first amplification stage as a result of the comparing step.12-01-2011
20120268212Amplifier Arrangement and Method for Operating an Amplifier Arrangement - An amplifier arrangement comprising an amplifier (AMP) with a terminal (SPL) for a supply signal (VSPL) and a bias circuit (BIAS) for providing the supply signal (VSPL) at the terminal (SPL). The bias circuit holds an operating point (OP) of the amplifier (AMP) constant by means of the supply signal (VSPL). The bias circuit (BIAS) comprises a reference circuit (REF) for providing a reference signal (VREF) and a correction device (COR) by means of which the supply signal (VSPL) is regulated based on the reference signal (VREF) and a correction signal (Vfeed), the correction signal (Vfeed) being dependent on the operating point (OP) of the amplifier (AMP). A method for operating an amplifier arrangement is also described.10-25-2012
20080265996Digital Hybrid Mode Power Amplifier System - A RF-digital hybrid mode power amplifier system for achieving high efficiency and high linearity in wideband communication systems is disclosed. The present invention is based on the method of adaptive digital predistortion to linearize a power amplifier in the RF domain. The power amplifier characteristics such as variation of linearity and asymmetric distortion of the amplifier output signal are monitored by the narrowband feedback path and controlled by the adaptation algorithm in a digital module. Therefore, the present invention could compensate the nonlinearities as well as memory effects of the power amplifier systems and also improve performances, in terms of power added efficiency, adjacent channel leakage ratio and peak-to-average power ratio. The present disclosure enables a power amplifier system to be field reconfigurable and support multi-modulation schemes (modulation agnostic), multi-carriers and multi-channels. As a result, the digital hybrid mode power amplifier system is particularly suitable for wireless transmission systems, such as base-stations, repeaters, and indoor signal coverage systems, where baseband I-Q signal information is not readily available.10-30-2008
20110169573AMPLIFIER CIRCUIT WITH STEP GAIN - A step gain amplifier has an amplifier with an input and an output, and a bias circuit connected to the input and to a bias node. A passive feedback circuit using only passive elements connects the output to the input. A control circuit is connected to the bias circuit at the bias node.07-14-2011
20090102563Transimpedance amplifier - The present invention solves characteristic deterioration caused by peaking and a ground inductance, and provides a transimpedance amplifier capable of achieving a higher gain and a wider band. For this purpose, the transimpedance amplifier is configured to include a feedback circuit having two or more extreme frequencies and having a filter characteristic which is flat with respect to frequencies in a frequency region not more than a smallest extreme frequency among the extreme frequencies, which is flat with respect to frequencies in a frequency region not less than a largest extreme frequency among the extreme frequencies, and which has at least one negative inclination portion with respect to frequencies in a frequency region between the smallest and largest extreme frequencies.04-23-2009
20120293265Radio Frequency Integrated Circuit - Embodiments of the invention are concerned with configurable RFICs. In an exemplary embodiment there is provided a configurable radio-frequency integrated circuit (RFIC) including one or more configurable low noise amplifier circuits, each of said one or more configurable low noise amplifier circuits being configurable between:11-22-2012
20080284520System And Method For Power Detection In A Power Amplifier - A system for detecting power output of a power amplifier includes a first power detector configured to detect a forward power output of a power amplifier, the first power detector configured to provide a first power detector output, and a second power detector configured to receive a collector parameter signal and detect a collector parameter therefrom, the second power detector also configured to provide a second power detector output.11-20-2008
20110204979CONSTRUCTIVE FEEDBACK TRAVELING WAVE DEVICE AND METHOD - An apparatus and method include a transmission line carrying a propagating signal between an inlet port and an outlet port. The propagating signal can include a forward traveling wave and optionally a backward traveling wave. A feedback stage samples a the propagating signal at the outlet port, generates a feedback signal the includes a time translation and a gain translation in the feedback energy, and routes the feedback signal to the inlet port such that the gain translation constructively interferes with the forward traveling wave and thereby increases the amplitude of the forward traveling wave. 08-25-2011
20120068771HETEROGENEOUS INTEGRATION OF HARMONIC LOADS AND TRANSISTOR FEEDBACK FOR IMPROVED AMPLIFIER PERFORMANCE - An RF power amplifier device in which the circuit is provided on two separate dies which are attached together vertically. According to one embodiment of the present invention, the RF power amplifier includes a first die including an amplifying circuit for amplifying an RF signal, and a second die including at least one circuit component coupled to the amplifying circuit. The first die is vertically coupled to the second die, and the second die may be a flip chip and include harmonic loads and/or feedback circuit.03-22-2012
20110221532SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE AND COMMUNICATION SYSTEM - According to an embodiment, a semiconductor integrated circuit device includes an amplifier and a feedback circuit. The amplifier includes an input terminal receiving an input signal and an output terminal outputting an output signal. The feedback circuit includes a first transistor generating a bias current. The feedback circuit is configured to operate based on the bias current. The feedback circuit is configured to receive the output signal to supply a feedback signal to the input terminal. A signal having a reverse phase to the output signal is input to a gate of the first transistor.09-15-2011
20090231042 Broadband Power Amplifier with A High Power Feedback Structure - A broadband power amplifier using a novel high power feedback structure is disclosed in this patent. Feedback is widely used in amplifier design to broaden the bandwidth of the amplifier. Traditionally, the feedback resistor is either an axial resistor placed over the top of the transistor or a surface mount resistor with a long PCB trace making up the rest of the feedback path. However, each of these methods has it's limitations. The axial resistor doesn't have good heat sinking capability and therefore cannot handle high power. The feedback on PCB makes the feedback path long and becomes positive feedback at high frequency, thus limiting the high end frequency of operation of the amplifier in a stable region. The feedback structure disclosed in this patent has a good heat sinking path, has very short feedback path; allowing for higher frequency operation. We successfully applied the feedback structures to a Gallium Nitride (GaN) transistor, which is a new type of power transistor that has low parasitic capacitance and high optimum load impedance, and demonstrated an amplifier with very high output power over extraordinarily broad bandwidth. Matching networks have been optimized to improve performance and stability. We have demonstrated that unconditional stability is achievable while operating over a broad bandwidth using this feedback structure.09-17-2009
20100148875 CIRCUIT FOR COMPENSATION OF LEAKAGE CURRENT-INDUCED OFFSET IN A SINGLE-ENDED OP-AMP - An electronic device includes an operational amplifier, with the operational amplifier having an amplifier input stage coupled with a first output node to an amplifier output stage. A compensation capacitance is connected between an output node of the amplifier output stage and the first output node of the amplifier input stage, thereby operating as a compensator for stabilizing the operational amplifier. The compensation capacitance provides a parasitic diode drawing a first leakage current from the first output node of the amplifier input stage, a leakage current compensation circuit being coupled to the first output node of the amplifier input stage and coupled to a second output node of the amplifier input stage for drawing a first current from the first output node and a second current from the second output node. The leakage current compensation circuit is adapted such that the second current is greater than the first current by an amount corresponding to the first leakage current.06-17-2010
20120105158Feedback Amplifier - Provided is a feedback amplifier including: an amplification circuit unit to generate an output voltage by amplifying an input voltage inputted through an input terminal; an output circuit unit to output the generated output voltage through an output terminal; a feedback circuit unit to control the gain of the amplification circuit unit by determining a total feedback resistance value using an external control signal and controlling an input current while the total feedback resistance value is determined; and a bias circuit unit to apply a bias voltage to the feedback circuit unit.05-03-2012
20110234320VOLTAGE OUTPUT DEVICE HAVING AN OPERATIONAL AMPLIFIER - A voltage output device which is capable of preventing an increase in circuit scale and includes an offset compensation function that is suitably applicable in particular to a drive circuit for display devices such as liquid crystal display panels. The voltage output device includes an operational amplifier which has an inverting input terminal and a non-inverting input terminal. Resistance values of a load resistor on the inverting input side and a load resistor on the non-inverting input side are maintained when the output voltage of the amplifier has changed while sequentially varying either one or both of the resistance values of the load resistor on the inverting input side and the load resistor on the non-inverting input side in a state that the inverting input terminal and the non-inverting input terminal are connected. The voltage output device is configured to output the output voltage of the amplifier with the inverting input terminal not connected to the non-inverting input terminal.09-29-2011
20090108940Amplifier - An amplifier comprises an input terminal that inputs an AC voltage signal; an amplifying unit having a transistor for amplifying the input AC voltage signal; a current detecting unit connected internally of said amplifying unit; and a control-current source controlled by said current detecting unit that drives an input stage of the transistor.04-30-2009
20100308919Methods and devices for leakage current reduction - Methods and devices for leakage current reduction are described. A regulator transistor is connected to a switch to bias the transistor with a first voltage during an ON state and a second voltage during the OFF state of the transistor. The switchable bias allows leakage current decrease and “on” resistance increase of the transistor.12-09-2010
20110084766WIDEBAND ACTIVE CIRCUIT WITH FEEDBACK STRUCTURE - A broadband active circuit with a feedback structure includes: an active load unit providing a load varied according to a control voltage; an active circuit unit connected between the active load unit and a ground and outputting a signal corresponding to a pre-set bandwidth, among input signals; and a feedback circuit unit formed between an output terminal of the active circuit unit and the active load unit and providing a signal from the output terminal of the active circuit unit to the active load unit.04-14-2011
20120200359AMPLIFIER ARRANGEMENT - An amplifier arrangement with an amplifier arrangement input and an amplifier arrangement output is disclosed. The amplifier arrangement comprises a first transistor and a first ballast resistance, wherein the first ballast resistance connects a first transistor base of the first transistor to a common base terminal at least one second transistor and at least one second ballast resistance, wherein the at least one second ballast resistance connects a second transistor base of the at least second transistor to the common base terminal; and a feedback device comprising a feedback input terminal for sensing at least a base voltage of the first transistor and further comprising a feedback output terminal that is connected to the common base terminal.08-09-2012
20110063035CONTROLLED-GAIN WIDEBAND FEEDBACK LOW NOISE AMPLIFIER - Provided is controlled-gain wideband feedback low-noise amplifier. The controlled-gain wideband feedback low-noise amplifier includes: a feedback amplifier configured to isolate an input signal and an output signal obtained by amplifying the input signal, feed back the output signal to the input signal to amplify wideband input signals, resonate a low-frequency band signal among the wideband input signals to amplify the low-frequency band signal among the wideband input signals, and be switched in accordance with a control signal to control an amplification gain of the low-frequency band signal among the wideband input signals; and a cascode amplifier configured to amplify a high-frequency band signal among the wideband signals inputted from the feedback amplifier, and be switched in accordance with a control signal to control an amplification gain of the high-frequency band signal among the wideband signals.03-17-2011
20110156818METHOD OF USING INTEGRATED POWER AMPLIFIER - An output-impedance in a power amplifier is provided. A first transistor Q06-30-2011
20120007681METHOD AND SYSTEM FOR A FEEDBACK TRANSIMPEDANCE AMPLIFIER WITH SUB-40KHZ LOW-FREQUENCY CUTOFF - A system for a feedback transimpedance amplifier with sub-40 khz low-frequency cutoff is disclosed and may include amplifying electrical signals received via coupling capacitors utilizing a transimpedance amplifier (TIA) having feedback paths comprising source followers and feedback resistors. The feedback paths may be coupled prior to the coupling capacitors at inputs of the TIA. Voltages may be level shifted prior to the coupling capacitors to ensure stable bias conditions for the TIA. The TIA may be integrated in a CMOS chip and the source followers may comprise CMOS transistors. The TIA may receive current-mode logic or voltage signals. The electrical signals may be received from a photodetector, which may comprise a silicon germanium photodiode and may be differentially coupled to the TIA. The chip may comprise a CMOS photonics chip where optical signals for the photodetector in the CMOS photonics chip may be received via one or more optical fibers.01-12-2012
20120019325CURRENT-MODE AMPLIFIER - A current-mode amplifier including an input stage, a feedback circuit and an output stage is provided. The input stage has an input terminal for receiving an input current of the current-mode amplifier. The input stage generates a corresponding inner current in accordance with the input current and a feedback current. The feedback circuit is connected to the input stage. The feedback circuit generates the corresponding feedback current in accordance with the inner current of the input stage. An input terminal of the output stage is connected to an output terminal of the input stage. An output terminal of the output stage serves as an output terminal of the current-mode amplifier.01-26-2012
20120025914CMOS POWER AMPLIFIER - A CMOS power amplifier includes: a first MOS transistor connected between a first power terminal and a first output stage and having a gate connected to an input stage; a second MOS transistor connected between the first output stage and a ground and having a gate connected to the input stage; a switching circuit unit connecting or separating a feedback line between the input stage and the first output stage to select a linear amplifying operation or a non-linear amplifying operation; and a resistor formed at the feedback line between the input stage and the first output stage to determine a linear amplification gain when the feedback line is turned on.02-02-2012
20120025913Envelope amplifier - An envelope amplifier includes an amplifier unit, a comparator unit and an output unit. The amplifier unit is made up of a first output section that outputs a first current in response to an amplitude of an input envelope signal, and a second output section. The second output section outputs a second current of a current value proportionate to a current value of the first current. Absolute value of the current value of the second current is greater than that of a current value of the first current. Comparator unit compares the current value of the first current. The output unit sums a current via an inductor derived from a current sustained or broken in response to a compared result of the comparator unit to the second current to deliver the resulting sum current at an output end. The first current is configured to be terminated without being delivered to the output unit (FIG. 02-02-2012
20100052791AMPLIFIER CIRCUIT - An amplifier circuit including: a multistage amplifier unit including an input-stage transistor and an output-stage transistor and configured to amplify an input signal and to output an amplified signal; and a feedback unit including a first feedback transistor, a second feedback transistor, and a feedback resistor, and configured to feed back the amplified signal to an input of the output-stage transistor in the multistage amplifier unit via the first feedback transistor, the second feedback transistor, and the feedback resistor.03-04-2010
20100052790AMPLIFIER CIRCUIT - An amplifier circuit includes a first amplifier amplifying an input signal and outputting a first amplified signal, a second amplifier amplifying the first amplified signal and outputting a second amplified signal, and a feedback circuitry feeding back the second amplified signal to the input of the second amplifier. The feedback circuitry includes a feedback transistor that keeps the input level of the second amplifier constant.03-04-2010
20120229216Distributed amplifier with improved stabilization - A distributed amplifier with improved stabilization includes an input transmission circuit, an output transmission circuit, at least one cascode amplifier coupled between said input and output transmission circuits. Each cascode amplifier includes a common-gate configured transistor coupled to the output transmission circuit, and a common-source configured transistor coupled between the input transmission circuit and the common-gate configured transistor. The distributed amplifier also includes a non-parasitic resistance and capacitance coupled in series between a drain and a gate of at least one of the common-gate configured transistors for increasing the amplifier stability.09-13-2012
20110304399Driver amplifier circuit and communication system - Disclosed herein is a driver amplifier circuit, including: a first current source transistor of a first conductivity type, and a second current source transistor of the first conductivity type, control voltages being supplied to gates of the first current source transistor and the second current source transistor, respectively; a first switching transistor of the first conductivity type, and a second switching transistor of the first conductivity type; a third switching transistor of a second conductivity type, and a fourth switching transistor of the second conductivity type; first, second, third, and fourth resistor elements; and a first output node and a second output node.12-15-2011
20120286874POSITIVE FEEDBACK COMMON GATE LOW NOISE AMPLIFIER - A Positive Feedback Common Gate Low Noise Amplifier (PFCGLNA) has positive feedback transistors and input transistors that are of the same conductivity type. Making the positive feedback and input transistors of the same conductivity type reduces sensitivity to process variations. Noise generated by the positive feedback transistors is used to cancel noise generated by the input transistors. In one embodiment, the PFCGLNA: 1) is tunable to have a substantially constant input impedance for any frequency in a wideband frequency range from 680 MHz to 980 MHz, and 2) has a noise figure less than 2.2 dB over the entire wideband frequency range. The input impedance of the PFCGLNA can be tuned to match a source that drives the PFCGLNA by setting a multi-bit digital control value supplied to a digitally-programmable tank load of the LNA.11-15-2012
20100201449AMPLIFIER - An amplifier including a first transistor including a gate coupled to an input terminal and a grounded source; a load resistor provided between a drain of the first transistor and a power supply; an output terminal coupled to a node between the drain of the first transistor and the load resistor; a feedback path coupled to the input terminal and the output terminal and including a resistor and a capacitor; a bias voltage generator applying a gate bias voltage to the gate of the first transistor in response to an enable signal; a supply resistor provided between an output node for the gate bias voltage of the bias voltage generator and the gate of the first transistor; and an enable switch lowering a resistance value between the output node for the gate bias voltage and a node in the feedback path.08-12-2010
20130009706ELECTRONIC DEVICE AND METHOD FOR AN AMPLIFIER WITH RESISTIVE FEEDBACK - An electronic device comprising an amplifier having at least a first input transistor of a first doping type. A first transistor is coupled with a channel as a feedback path between an output of the amplifier and a control gate of the first input transistor forming an input of the amplifier. A diode-coupled second transistor is coupled with a channel between a first current source and the output of the amplifier wherein a control gate of the first transistor is coupled between the first current source and the diode-coupled second transistor and the first transistor is of a second doping type which is opposite to the first doping type of the first input transistor of the amplifier.01-10-2013
330292000 Having compensation for interelectrode impedance 4
20090261907INTEGRATED CIRCUIT HAVING ON DIE STRUCTURE PROVIDING CAPACITANCE IN AMPLIFIER FEEDBACK PATH - An amplifier structure includes shield conductors that are provided spatially adjacent to elongated feedback signal lines that couple a feedback circuit to an amplifier input. The shield conductors are provided between the feedback signal lines and a ground plane, which interrupts a parasitic capacitance that otherwise would be established between the feedback signal line and ground. The shield conductors are electrically coupled to the amplifier's outputs which create a capacitance between the output terminal and the feedback signal line. In some embodiments, the capacitance generated between the output terminal and the feedback signal line can suffice as a capacitor in a feedback path of the amplifier and be contained in an integrated circuit die on which the amplifier is manufactured. Optionally, a structure may be provided that eliminates common mode signals on the feedback lines while simultaneously preserving the common mode signals on the amplifier output terminals. In this option, a second amplifier is provided that, in response to common mode variations at the output terminal, generates counterbalancing voltage variations on a second circuit that is coupled to the feedback lines at their source. The two variations cancel each other out at nodes from which the feedback lines originate, which substantially reduces feedback common mode variation even when there is common mode variation at the output terminals.10-22-2009
20080238552SEMICONDUCTOR DEVICE - A semiconductor device includes a phase compensation circuit 10-02-2008
20090066421Internal frequency compensation circuit for integrated circuit controllers - A frequency compensation circuit internal to an integrated circuit which comprises a transconductance amplifier having a first input configured to receive a reference voltage, a second input configured to receive an input voltage and an input current, a first output configured to output a first output current and a second output configured to output a second output current; and a compensation circuit connected to said second output of said transconductance amplifier, wherein said first output is connected to said second input.03-12-2009
20120313711DEVICE FOR NEUTRALIZING A SIGNAL OBTAINED BY MODULATING, ON TO A HIGH FREQUENCY CARRIER, A USEFUL SIGNAL DELIVERED BY A SYSTEM - The invention relates to a device for neutralizing a signal obtained by modulating, on to a high frequency carrier, a useful signal delivered by a system comprising a parasitic capacitance Cp that varies over time, the device comprising a neutralizing capacitance Cn, means for providing an adjustable gain G, said means being equipped with a JFET field-effect transistor (J12-13-2012
330293000 Having negative feedback 17
20090115528Low Cost High Performance Power Amplifier Utilizing Two-Stage-Included Local Negative Feedback with Feedback-Shifting Technology - The present invention provides a cost-effective and power-effective solution to a high performance amplifier design over conventional Class A and Class B/AB amplifiers. Without increasing cost or losing simplification of conventional Class B/AB amplifier configuration, two kinds of unique local feedback loops, which cover the second and third stages and further offer a feedback shifting feature over frequency range, are disclosed to replace the traditional Miller compensation capacitor to suppress dominant distortion, which is usually generated by the two last stages while maintaining stability of the amplifier, through high frequency end. Since the present invention provides key elements of a three-stage amplifier that enable performance improvement in a wide range of circuit design, the present invention has significant commercial values in amplifier circuit industries including audio power amplifiers, IC (integrated circuit) operational amplifiers, ADC (Analog-to-Digital Conversion) and DAC (Digital-to-Analog Conversion) buffers, etc.05-07-2009
20100097146Signal amplification circuit - This invention provides a low-current consumption type signal amplification circuit, which limits the output voltage to fix a lower-limit (upper-limit) saturation voltage of the amplification circuit at a predetermined lower-limit (upper-limit) limiting voltage. The signal amplification circuit comprises a negative feedback amplification circuit, a lower-limit voltage limiting circuit and an upper-limit voltage limiting circuit. The lower-limit voltage limiting circuit increases a resistance between an output terminal of the negative feedback amplification circuit and a ground terminal when the output voltage of the negative feedback amplification circuit falls below the lower-limit limiting voltage. The upper-limit voltage limiting circuit increases a resistance between the output terminal of the negative feedback amplification circuit and a high-potential side of a power supply when the output voltage of the negative feedback amplification circuit rises above the upper-limit limiting voltage.04-22-2010
20120218043Amplifier Activation - An amplifier comprises a main amplification stage and an auxiliary amplification stage. An input of the main amplification stage and an input of the auxiliary amplification stage are coupled to a common node, and an output of the main amplification stage is coupled to an output node. During activation, before power is supplied to the main amplification stage, the output node is coupled to a reference voltage (V08-30-2012
20120194274INTEGRATED CIRCUIT, WIRELESS COMMUNICATION UNIT AND METHOD FOR PROVIDING A POWER SUPPLY - An integrated circuit is described for providing a power supply to a radio frequency (RF) power amplifier (PA). The integrated circuit includes a low-frequency power supply path including a switching regulator and a high-frequency power supply path arranged to regulate an output voltage of a combined power supply at an output port of the integrated circuit for coupling to a load. The combined power supply is provided by the low-frequency power supply path and high-frequency power supply path. The high-frequency power supply path includes: an amplifier including a voltage feedback and arranged to drive a power supply signal on the high-frequency power supply path; and a capacitor operably coupled to the output of the amplifier and arranged to perform dc level shifting of the power supply signal.08-02-2012
20120139639Ground Partitioned Power Amplifier for Stable Operation - Achievement of robust stability of a power amplifier (PA) that allows the sharing of the ground between the driver stages and the output stage is shown. A controlled amount of negative feedback is used to neutralize the local positive feedback that results from the driver-to-output stage ground sharing in the signal path, for example, a radio frequency (RF) signal path. The solution keeps a strong drive and a good performance of the PA. Exemplary embodiments are shown for the PA positive feedback neutralization. A first embodiment uses a ground signal divider while another embodiment uses a ground signal divider weighting technique.06-07-2012
20090184769NEGATIVE-FEEDBACK TYPE ULTRA-WIDEBAND SIGNAL AMPLIFICATION CIRCUIT - A negative-feedback type ultra-wideband signal amplification circuit is proposed, which is designed for integration to an ultra-wideband (UWB) signal processing circuit system for providing a low-noise amplification function to UWB signals. The proposed circuit architecture is characterized by the provision of a dual-step filter circuit on the input side, the provision of a resistive-type feedback circuit in the transistor-based amplification circuitry, and the provision of a common-source transistor-based amplification circuit on the output side. These features allow the proposed signal amplification circuit to have flat power gain, lower power consumption, low noise figure, and higher operational stability.07-23-2009
20110140785CMOS AMPLIFIER WITH INTEGRATED TUNABLE BAND-PASS FUNCTION - A CMOS amplifier with integrated tunable band-pass function, a tunable active resistor structure, a method of amplifying an input signal and a method of fabricating an amplifier. The tunable active resistor structure comprises two symmetrically cross-coupled transistors.06-16-2011
20100001801INTERMODULATION SIGNAL GENERATOR OF POWER AMPLIFIER AND PRE-DISTORTION LINEARIZER HAVING THE SAME - Provided are an intermodulation signal generator of a power amplifier and a pre-distortion linearizer having the same. The intermodulation signal generator of the power amplifier includes: a circulator for outputting a radio-frequency (RF) input signal input via a first port to a second port and outputting an intermodulation signal input via the second port to a third port; a directional coupler for shifting phases of the input signals input via the second port of the circulator to divide or couple the phase-shifted signals; first and second Schottky diodes, disposed symmetrically, for receiving the signals divided by the directional coupler to generate intermodulation signal components; first and second phase adjusters, disposed symmetrically, for controlling phases of the intermodulation signal components gene rated by the first and second Schottky diodes by means of first and second bias voltages; and first and second scalers, disposed symmetrically, for controlling magnitudes of the intermodulation signal components generated by the first and second Schottky diodes by means of third and fourth bias voltages. The above-described intermodulation signal generator can be applied to a power amplifier of a high-performance downscaled communication system.01-07-2010
20100148876Amplifier Arrangement and Method for Amplifying a Signal - An amplifier arrangement has an amplifier (06-17-2010
20110109392LOW NOISE AMPLIFIER - Provided is a Low Noise Amplifier (LNA). Embodiments of the present invention provide LNAs including: a common gate amplifier circuit configure to amplify a signal of an input node to which an Alternating Current (AC) component is provided and transfer the amplified signal to an amplifier node; and a negative-feedback amplifier circuit configured to amplify a signal of the amplifier node, transfer the amplified signal to an output node, wherein the negative-feedback amplifier circuit includes a feedback capacitor and a feedback inductor connected in series between the amplifier node and the output node to form a negative feedback. the LNA of the present invention forms a negative feedback exclusive of a feedback resistance, such that a broad frequency bandwidth is obtained and noise and heat are reduced.05-12-2011
20110148527Dual-Loop Feedback Amplifying Circuit - An amplifying circuit arranged for converting an input signal into an amplified output signal comprising: an input node (06-23-2011
20100066452WIDEBAND LOW-NOISE AMPLIFIER - A wideband low-noise amplifier of the present invention is designed such that an input terminal is connected to a base of a first transistor, one terminal of a first passive element, and one terminal of a third passive element; an emitter of the first transistor is grounded; a collector of the first transistor is connected to an output terminal, a base of a second transistor, one terminal of a capacitor, and one terminal of a second passive element; the other terminal of the first passive element is connected to the other terminal of the capacitor; an emitter of the second transistor is connected to the other terminal of the third passive element; and a power terminal is connected to a collector of the second transistor and the other terminal of the second passive element, wherein impedance of the third passive element is determined based on impedance of the first transistor whose emitter size is determined to suite desired saturation level of amplification, thus establishing input impedance matching.03-18-2010
20120056675Operational Amplifier For An Active Pixel Sensor - The present invention includes operational amplifier for an active pixel sensor that detects optical energy and generates an analog output that is proportional to the optical energy. The active pixel sensor operates in a number of different modes including: signal integration mode, the reset integration mode, column reset mode, and column signal readout mode. Each mode causes the operational amplifier to see a different output load. Accordingly, the operational amplifier includes a variable feedback circuit to provide compensation that provides sufficient amplifier stability for each operating mode of the active pixel sensor. For instance, the operational amplifier includes a bank of feedback capacitors, one or more of which are selected based on the operating mode to provide sufficient phase margin for stability, but also considering gain and bandwidth requirements of the operating mode.03-08-2012
20120056674Amplification of an Incoming Signal Received Via an Antenna - In one embodiment, a method includes receiving a radio frequency (RF) at an antenna; generating negative feedback to linearize an amplifier by resistively or transformer coupling an output signal of a transistor of the amplifier to the input of the transistor; generating a rectified voltage by rectification of the output signal of the transistor; generating a constant reference voltage; and outputting a control voltage or a control current to the transistor based on the sum of the reference voltage and a first voltage derived from the rectified voltage. The output of the control voltage or control current facilitates control of an operating point of the transistor.03-08-2012
20110080220TEMPERATURE COMPENSATED INTEGRATOR - A representative integrator includes an amplifier having an input and an output; a feedback loop coupled between the input and the output of the amplifier, the feedback loop comprising a compensated resistor circuit having a resistance value selected for reducing a loss factor of the integrator; and a control circuit coupled to an input of the compensated resistor circuit, the control circuit producing a control signal for controlling the compensated resistor circuit to substantially maintain the resistance value selected for reducing the loss factor of the integrator across a range of integrator temperatures.04-07-2011
20080252379High slew rate amplifier, analog-to digital converter using same, CMOS imager using the analog-to-digital converter and related methods - An amplifier, which may be used in a pipelined analog-to-digital converter, includes a first amplifier stage driving a second amplifier stage. At least one compensation capacitor is coupled to provide negative feedback through the capacitor from the second amplifier stage to the first amplifier stage. The slew rate of the amplifier is enhanced by substantially reducing the negative feedback coupled through the capacitor during a period following the transition of a signal applied to an input terminal of the amplifier. If the first stage of the amplifier has complementary signal nodes, the negative feedback coupled through the capacitor may be reduced, for example, by closing a switch coupled between first and second complementary nodes of the first amplifier stage.10-16-2008
20120274404MIXED-SIGNAL INTEGRATOR ARCHITECTURE - A mixed signal correlator utilizes coherent detection within a capacitance measurement application. In some applications, the mixed signal correlator is used to measure capacitance of a touch screen display. An external capacitor whose capacitance is measured is kept small for improved sensitivity and can be used for a variety of applications having varied integration periods for measurement. The external capacitor is kept small and can be used for varied applications by adjusting the output voltage within a range that is less than the supply voltage, and maintaining a count of the adjustments to later reconstruct an actual output voltage for the integration period. An output is a weighted sum of an analog integrator output and a digital counter output.11-01-2012
330294000 Having frequency-responsive means or phase-shift means in feedback path 5
20110291764LINEAR FET FEEDBACK AMPLIFIER - A circuit that includes a Darlington transistor pair having an input transistor and an output transistor configured to generate an output signal at an output node in response to an input signal received through the input node is disclosed. The circuit has a frequency bias feedback network communicatively coupled between the output transistor and the input node for providing biasing to the Darlington transistor pair as well as for adjusting a phase and amplitude of an amplified version of the input signal that passes through the input transistor and into the frequency bias network. The circuit further includes a feedback coupling network coupled between the output node and the input node for feeding back to the input node a portion of the amplified version of the input signal that passes through the input transistor.12-01-2011
20080284521Electronic Signal Processor - An electronic signal processor for processing signals includes a complex first filter, one or more gain stages and a second filter. The first filter is characterized by a frequency response curve that includes multiple corner frequencies, with some corner frequencies being user selectable. The first filter also has at least two user-preset gain levels which may be alternately selected by a switch. Lower frequency signals are processed by the first filter with at least 12 db/octave slope, and preferably with 18 db/octave slope to minimize intermodulation distortion products by subsequent amplification in the gain stages. A second filter provides further filtering and amplitude control. The signal processor is particularly suited for processing audio frequency signals. Related methods include filtering the input signal with an input filter of the second or third order high pass type, amplifying the filtered signal and further filtering the amplified signal with a low pass filter, which may be of the second order type.11-20-2008
20100301946Switchable Multiband LNA Design - A low noise amplifying (LNA) circuit comprising an amplifying section (12-02-2010
20100134190Programmable Compensation Network for Operational Amplifiers - Systems and methods for implementing a programmable network for a multimode conditionally stable operational amplifier are disclosed.06-03-2010
20120001694ADAPTIVE CARTESIAN LOOP TRANSMITTER FOR BROADBAND AND OPTIMAL LOOP STABILITY ADJUSTMENT - An integrated circuit includes a linearizer circuit in which excessive delay is compensated. The linearizer circuit includes a power amplifier, forward and feedback paths, and a microprocessor. A signal from the power amplifier is routed by the forward path to be transmitted while a portion of the signal to be transmitted is routed back to the power amplifier via the feedback path. The microprocessor applies phase training signals to the forward path. The microprocessor uses the phase training signals to determine the amount of delay in the linearizer circuit and alters the frequency position of poles and zeros in the linearizer circuit to compensate for the delay. The gain of the linearizer circuit is also altered by the microprocessor depending on the measured delay.01-05-2012

Patent applications in class Including signal feedback means

Patent applications in all subclasses Including signal feedback means