Abstract: A differential circuit and an amplifier circuit for reducing an amplitude difference deviation, performing a full-range drive, and consuming less power are disclosed. The circuit includes a first pair of p-type transistors and a second pair of n-type transistors. A first current source and a first switch are connected in parallel between the sources of the first pair of transistors, which are tied together, and a power supply VDD. A second current source and a second switch are connected in parallel between the sources of the second pair of transistors, which are tied together, and a power supply VSS. The circuit further includes connection changeover means that performs the changeover of first and second pairs between a differential pair that receives differential input voltages and a current mirror pair that is the load of the differential pair. When one of the two pairs is the differential pair, the other is the current mirror pair.

Abstract: A Class AB voltage-to-current converter includes a plurality of DC coupled transconductance stages that produce a linearized output and a biasing circuit. The biasing circuit generates a primary bias voltage that is greater than a generated secondary bias voltage. As such, the first transconductance stage becomes active before the second transconductance stage with respect to the magnitude of a differential input voltage, thereby allowing the transconductance of the secondary transconductance stage to be added (or subtracted) from the transconductance of the primary stage to improve the overall transconductance of the Class AB voltage-to-current converter. As each of the plurality of transconductance stages is biased differently from the others, the various transconductance stages are biased on to differing amounts based upon the biasing signals as well as the input signal.

Abstract: A bias circuit for a smart power amplifier includes a high power mode bias circuit and a low power mode bias circuit, and operates only one of the bias circuits selectively using a switching circuit according to an input signal. Therefore, the bias circuit of high power mode and the bias circuit of the low power mode are divided and can be optimized according to characteristics of the power. Accordingly, a gain difference with respect to each power can be minimized and the low power mode can be controlled with a small amount of current in a state of initial current with a low power and in a middle power, such that an efficiency of the power amplifier can be improved at low power.

Abstract: In order to provide an interface circuit, a power converter using the same and an electric vehicle using the same, wherein this interface circuit ensures improved control reliability without employing a photo-coupler, an interface circuit 100A transfers control signals to the power transistor in a large-current circuit 300 from a small-signal circuit 200 for driving a power transistor. The interface circuit 100A has a noise absorber 120 that electrically absorbs a noise voltage produced between the ground of the small-signal circuit 200 and that of the power transistor. The noise absorber 120 transfers to the power transistor the control signals generated by the small-signal circuit 200, without being affected by the noise voltage if produced.

Abstract: There is provided a high frequency power amplifier circuit capable of enhancing detection accuracy of an output level, necessary for feedback control of the high frequency power amplifier circuit, and capable of executing output power control with higher precision, With the high frequency power amplifier circuit, the detection of the output level, necessary for feedback control of the high frequency power amplifier circuit is executed by use of a current detection method, and in an electronic device comprising a differential amplifier for comparing an output power detection signal with an output level designation signal and for generating a signal for controlling a gain of the high frequency power amplifier circuit according to a potential difference between the two signals, a power source voltage with variation less than that for the power source voltage of the high frequency power amplifier circuit is used as the operational power source voltage of the output power detection circuit.

Abstract: Providing a high frequency power amplifier circuit and a radio communication system which can control output power by a power voltage, produce sufficient output power in high regions of demanded output power and improve power efficiency in low regions of demanded output power. In a high frequency power amplifier circuit (RF power module) which comprises two or more cascaded FETs for amplification and controls output power by controlling power voltages of the FETs for amplification to gate terminals of which bias voltages of a predetermined level are applied, different transistors for power voltage control are provided for a last-stage FET for amplification and preceding-stage FETs for amplification. The transistors for power voltage control generate and apply the power voltage so that the preceding-stage FETs for amplification saturate when a demanded output level is relatively low.

Abstract: A multi-band power amplifier module includes a first power amplifier that amplifies a first input radio frequency signal in a first frequency band in response to a first bias control signal. A second power amplifier amplifies a second input radio frequency signal in a second frequency band in response to a second bias control signal. A first bias control circuit produces the first bias control signal and a second bias control circuit produces the second bias control signal in response to step gain signals received at a step gain terminal.

Abstract: In an RF communication system, aspects of constant or proportional to absolute temperature biasing for minimizing transmitter output power variation may comprise configuring at least one current source to provide a temperature dependent current, where the current may be constant with temperature or vary proportionally to absolute temperature. A control voltage that may be generated by an operational amplifier may be fed back to control the current source. An input reference voltage may also be generated for the operational amplifier by utilizing PN junction characteristics of at least one bipolar junction transistor. Resistance may be adjusted to allow operation of the current source at a plurality of different supply voltages, including the different supply voltages that may be less than 1.2 volts, for example. Additionally, adjusting the resistance may also allow the current to be constant with temperature or vary with temperature.

Abstract: The input stage of the fully differential amplifier output stage is configured in a differential pair configuration with a tail current. The tail current is divided between two legs of the input stage and is higher in the leg that has the higher of the two input voltage levels (in or inb). The devices in each leg of the fully differential amplifier output stage may be cascoded to avoid electrical voltage overstress. The top device in each leg of the differential input stage may be coupled in a diode configuration and is utilized to mirror the current into another NMOS current mirror as well as to a PMOS output device. The gate of the PMOS output devices are connected in a cross-coupled configuration. The NMOS current mirrors are utilized to mirror the current into the NMOS output devices in a non-cross-coupled configuration.

Abstract: A wireless communication system has a first operation mode (GSM mode) for amplifying a phase-modulated high frequency signal with a high frequency power amplifier circuit and a second operation mode (EDGE mode) for amplifying a phase and amplitude-modulated high frequency signal with the amplifier circuit. The amplifier circuit has an input of a high frequency signal, with the amplitude and frequency being fixed in both the first and second operation modes, and operates by being controlled for the bias state of each amplifying stage in accordance with the output control signal produced by a control circuit based on the demanded output level (Vapc) and the detected output level (VSNS) so that the amplifier circuit performs signal amplification to meet the demanded output level.

Abstract: The present invention provides a high frequency power amplifier of an open-loop type, which outputs a signal having a level corresponding to an output level required under control of a power supply voltage for each output power FET, based on a control signal for the output level. The high frequency power amplifier is provided with a bias voltage generating circuit which generates a gate bias voltage of each output power FET according to an output voltage of a power control circuit for controlling the power supply voltage for the output power FET, based on the control signal for the output level.

Abstract: A low-noise amplifier includes a first amplification device. The first amplification device includes a control terminal, a first terminal, and a second terminal. The low-noise amplifier also includes a feedback circuit in communication with the control terminal and the first terminal. The feedback circuit compares a voltage, corresponding to an output current associated with the first terminal, with a predetermined reference voltage to generate a bias signal applied to the control terminal for biasing the low-noise amplifier.

Abstract: Power control circuitry for providing a variable supply voltage to power amplifier circuitry in such a manner as to reduce or essentially eliminate variations in output power due to variations in load impedance is provided. The power control circuitry includes a voltage regulator for providing the variable supply voltage to the power amplifier circuitry, current detection circuitry, correction circuitry, and combiner circuitry. In operation, the current detection circuitry provides a signal indicative of an actual current provided to the power amplifier circuitry from the voltage regulator. The correction circuitry provides a correction signal based on a comparison of the signal indicative of the actual current and a signal indicative of a reference current. The combiner circuitry operates to combine the correction signal and the adjustable power control signal to provide the corrected adjustable power control signal to the voltage regulator.

Abstract: A method and apparatus is provided for use with a power amplifier to provide a regulated supply to the power amplifier. The invention uses a combination of voltage and current regulation to overcome the problems encountered in the prior art. In one example, voltage regulation is used at high power levels, while current regulation is used at low power levels.

Abstract: A transmit power amplifier of a wireless terminal is controlled by determining a power supply voltage applied to the transmit power amplifier, determining a power supply current provided to the transmit power amplifier, determining a relationship of the determined power supply current and the determined power supply voltage, and controlling the power supply voltage responsive to the determined relationship of the power supply current and the power supply voltage. For example, determining a relationship of the determined power supply current and the determined power supply voltage may include determining whether the power supply current meets a predetermined criterion, e.g., a predetermined current range, associated with the determined power supply voltage. The invention may be embodied as apparatus, methods, and computer program products.

Abstract: 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 impedance electrical element reduces the amount of bias circuit noise introduced into the output signal. In an embodiment, the high impedance electrical element includes an inductor and a capacitor connected in parallel. In another embodiment, the high impedance electrical element includes a grounded transmission line.

Abstract: An amplifier includes a Darlington transistor pair and a biasing network to increase bias currents in an input transistor.

Abstract: A multi-band power amplifier module includes a first power amplifier that amplifies a first input radio frequency signal in a first frequency band in response to a first bias control signal. A second power amplifier amplifies a second input radio frequency signal in a second frequency band in response to a second bias control signal. A first bias control circuit produces the first bias control signal and a second bias control circuit produces the second bias control signal in response to step gain signals received at a step gain terminal.

Abstract: A method and system are disclosed for controlling pop noises in a sound broadcasting system. After controllably connecting an output of a drive amplifier to a first predetermined low voltage level through a first switch, a first portion of an operation control data set is input to a digital-to-analog converter (DAC) circuit for driving an output thereof to a second predetermined low voltage level, and a second portion of the operation control data set is also input to the DAC circuit and further to the drive amplifier to bring the output of the drive amplifier to a common mode voltage level over a predetermined rise-up time period for controlling the pop noises.

Abstract: A method and apparatus are provided for operating a transmission amplifier, particularly a mobile communications terminal, with the transmission amplifier being fed with a supply voltage and with any nonlinearity of the transmission amplifier being substantially compensated for via a predistortion unit for data values in an input data stream, wherein, at least at the start of transmission operation or after a considerable change in the operating parameters, the transmission amplifier is operated with a supply voltage which is of such a magnitude that the transmission amplifier operates in the linear region, and the supply voltage for the transmission amplifier is reduced to the extent to which a quality factor for the compensation for the nonlinearity of the transmission amplifier is increased by the predistortion unit.

Abstract: A multi-band power amplifier module includes a first power amplifier that amplifies a first input radio frequency signal in a first frequency band in response to a first bias control signal. A second power amplifier amplifies a second input radio frequency signal in a second frequency band in response to a second bias control signal. A first bias control circuit produces the first bias control signal and a second bias control circuit produces the second bias control signal in response to step gain signals received at a step gain terminal.

Abstract: A power device(s) is biased and operates in Class-AB. Crossover distortion is minimized over a broad range of operating conditions, not only for a nominal case. The bias current of a power transistor is automatically adjusted in response to process and temperature variations. Preferably, the adjustment is performed using an error-feedback arrangement. An exemplary ‘rule’ for bias adjustment involves satisfying a proportionality relationship between the small-signal device transconductance at the operating point, and a maximum device transconductance. A dual replica master-slave control architecture is utilized. A self-adapting circuit is provided to change the bias current (or voltage) so that the value is always the optimum value, irrespective of operating temperature and/or process variations. Self-biasing is introduced wherein no manual adjustment is necessary. A stable amplifier is formed having great robustness to process and temperature variations.

Abstract: A low noise amplifier (500) includes a first transconductance device (326) having a control electrode for receiving a first input signal, and a first current electrode; a first load device (322) having a first terminal coupled to a first power supply voltage terminal and a second terminal coupled to the first current electrode of the first transconductance device (326) and forming a first output voltage signal; a second transconductance device (336) having a control electrode for receiving a second input signal, and a second current electrode; a second load device (332) having a first terminal coupled to the first power supply voltage terminal and a second terminal coupled to the first current electrode of the second transconductance device (336) and forming a second output voltage signal; and an attenuation device (340) coupled between the first current electrodes of the first (326) and second (336) transconductance devices and having a control input terminal for receiving a control voltage thereon.

Abstract: The present invention provides a power amplifier module featuring that: its output power characteristic smoothly changes as the input control voltage changes; and its control sensitivity is stable over a wide dynamic range. By same means, idling current for gain setting is supplied to a single amplifier element or all of multiple stages of amplifier elements of the power amplifier module. By making this idling current behave so as to exponentially change, relative to input control voltage, the invention enables output power control proportional to the input control voltage.

Abstract: A module including a bias circuit that generates gate bias voltages by resistance dividers creates a problem in that the values of the resistances constituting the bias circuit must be finely adjusted, and accordingly extra trimming tasks are required. The present invention provides current generators that generate currents varying with desired characteristics responsive to a control voltage, independent of variations in transistor threshold voltages, connects output resistors to parallel transistors in respective stages to form current mirror circuits, and supplies currents from the current generators thereto to drive them, instead of supplying dividing voltages.

Abstract: A device for amplifying or attenuating HF signals is characterized in that a transistor is connected in a common-emitter configuration in amplifying operation, and a base-collector diode is connected in the forward-biased direction for attenuating operation.

Abstract: An amplifier circuit for amplifying radio frequency signals having temperature compensation and bias compensation includes a radio frequency power amplifier that receives an input radio frequency signal and outputs an amplified radio frequency signal, and a first transistor performing as a detector diode with its collector and base connected. The base of the first transistor receives the amplified radio frequency signal from the power amplifier, a second DC bias input signal from a regulated DC source, and a third power-sensing signal. The amplifier circuit further includes a second transistor to amplify the DC component of the RF signal from the base of the first transistor. The base of the second transistor is coupled to the base of the first transistor. The collector of the second transistor outputs the power-sensing signal, which is coupled to the regulated DC source through a resistor.

Abstract: Differential amplifiers are provided that substantially cancel the input bias currents at the inputs to the differential amplifiers. A circuit produces a compensation current that is substantially equal in magnitude but opposite in polarity to input bias currents associated with the first and second inputs of the differential amplifier. A further pair of transistors are used to replicate the compensation current, and to provide replicated compensation currents to the inputs of the differential amplifier, thereby substantially canceling the input bias currents at the inputs.

Abstract: The present invention provides a high frequency power amplification circuit capable of preventing an output power and current consumption from being largely changed even when a load fluctuates in a wireless communication system for detecting an output level necessary for feedback control by a current detecting method. In a high frequency power amplification circuit as a component of a wireless communication system which detects an output level necessary for feedback control by a current detecting method, a capacitive element is interposed between the drain terminal of a power amplification transistor in the final stage and the gate terminal of a transistor constructing a current mirror circuit in a circuit for detecting an output level, and a change in an output power accompanying load fluctuation is reflected in a detection current of the output level detecting circuit.

Abstract: An amplifier includes a main amplifier circuit and at least one auxiliary amplifier circuit. Portions of an RF signal to be amplified are delivered to the main and auxiliary amplifiers. The auxiliary amplifier circuit is selectively operable to operate in combination with the main amplifier circuit, such as based on the level of the RF signal. At least one hybrid coupler circuit has input ports coupled with outputs of the main amplifier circuit and auxiliary amplifier circuit. The hybrid coupler circuit is operable to combine amplifier circuit output signals at a coupler first output port. A coupler second output port is terminated with one of an electrical short and an electrical open circuit.

Abstract: A power supply voltage required on the basis of information of setting transmission power to be output is supplied, thereby minimizing power consumption. A transmission circuit comprises a driver amplifier 3 whose gain is controlled by a first control voltage Vc1 for setting transmission power and a power amplifier 4 connected to the post-stage of the power amplifier 3. A power supply circuit 5 to which the first control voltage Vc1 is input and whose output voltage is controlled by the first control voltage Vc1 is provided. A voltage required for the power amplifier 4 when outputting the transmission power set by the first control voltage Vc1 is supplied from the power supply circuit 5.

Abstract: A power amplifier comprises first and second power transistor stages that receive first and second supply voltages, respectively. First and second bias circuits provide the biasing for the first and second power transistor stages, respectively, in response to a reference voltage and a bias voltage.

Abstract: An RF amplifier is disclosed having a first and second current mirror module. The first and second current mirror modules each provide current to affect the quiescent bias current of the RF amplifier.

Abstract: A low-noise amplifier circuit is specified which has a switchable gain ratio. For this purpose, a parallel circuit comprising a first and a second current path (3, 4) is provided between a radio-frequency signal input and output (1, 2), with the first current path (3) having a transistor which is connected in a common-base circuit for signal amplification, and the second current path (4) having a transistor which is connected in a common-emitter circuit (7) for signal amplification, and has input impedance matching (25, 27). Owing to the good noise characteristics and the good linearity characteristics, the described low-noise amplifier circuit is suitable for use in radio-frequency receivers in which adaptive pre-amplification is required even before a frequency converter, that is to say at the radio-frequency level, because the input signal has a wide dynamic range, such as that in the case of UMTS.

Abstract: A bias circuit is provided to present a controlled impedance to an input of an RF amplifier to improve linearity of the RF amplifier. The bias circuit may control the impedance such that a low impedance is presented to the input of the amplifier at low frequencies and a high impedance is presented to the input of the amplifier at high frequencies.

Abstract: A switching multi-phase DC-DC converter is provided that includes a current feedback loop for each phase of the multi-phase converter and a voltage feedback loop providing a set-point to each of the current feedback loops. The combination of the current feedback loops and the voltage feedback loop operates to balance the currents in each of the phases of the multi-phase DC-DC converter such that the currents have substantially the same magnitude.

Abstract: An apparatus and method for amplifying a radiofrequency (RF) signal. The apparatus comprises a control circuit including a first transistor, a second transistor, and a ballast resistor coupled between an emitter terminal of the first transistor and a base terminal of the second transistor, such that a control voltage applied to a base terminal of the first transistor controls the amplification of a signal applied to the base terminal of the second transistor. Additional elements may be coupled to the control circuit to improve the performance thereof, including a feedback stabilization circuit, a diode stack circuit, a bypass capacitor and an additional resistor.

Abstract: A multistage high frequency power amplifier circuit device has a plurality of semiconductor amplification elements connected in a cascade. The circuit device is provided with a bias control circuit used to control the bias voltage or bias current of the output semiconductor amplification element in each stage so as to reduce the variation of the output power with respect to the power control signal voltage in an area around the threshold voltage of the semiconductor amplification elements. This realizes a high frequency power amplifier circuit device provided with excellent controllability of the output power and high efficiency at the time of low power output realized with use of such a control voltage as a power control signal.

Abstract: A bias boost circuit is disclosed for use with an amplifier circuit for biasing thereof. The amplifier circuit includes at least a first transistor and a filter circuit for filtering of current pulses received from the bias boost circuit, where filtered current pulses form a variable bias current that is provided to the at least a first transistor. With this type of biasing circuit, large input signals that would normally compress the gain of the amplifier circuit are therefore amplified with less gain compression by virtue of the boost in bias current that is supplied to the at least a first transistor.

Abstract: A method for regulating the power supplied to an amplifier by providing the power supply input of the amplifier with a current via a coil or a diode connected to a constant voltage power supply, and with additional current diverted from a controlled current source, wherein the magnitude and direction of the additional current is adjusted according to a modulating signal.

Abstract: A radio frequency circuit includes a radio frequency signal source which produces a radio frequency signal, a power amplifier which power amplifies the radio frequency signal from the radio frequency signal source, and a control unit which controls an output power of the power amplifier. Particularly, the control unit is configured to hold control data defining a relationship among an output power, a gain, and an operation bias point of the power amplifier and adjust the operation bias point of the power amplifier based on the control data such that the output power of the power amplifier is set into a level designated by an external power designating instruction.

Abstract: A power amplifier having a first amplifier output stage and a parallel second amplifier output stage is provided. The first amplifier output stage is enabled (i.e., fully biased) during both high power and low power operating modes. The second amplifier output stage is disabled during the low power operating mode, and enabled during the high power operating mode. Because neither the first nor second amplifier output stage is operated in an extremely low quiescent current state, the linearity of the power amplifier is maintained for both high power and low power operating modes.

Abstract: A high-power amplification circuit includes a first transistor which amplifies an input signal, a bias circuit which includes a second transistor which is an emitter follower, and supplies a bias current to a base of the first transistor, a constant-voltage power supply connected to the base of the second transistor through a first resistor, a control voltage terminal input one of a first control and a second control voltage, a third transistor including a base connected to the control voltage terminal through a second resistor, a third resistor connected between the base of the second transistor and the collector of the third transistor, and a fourth transistor connected between the base of the second transistor and the third resistor, the fourth transistor being diode-connected.

Abstract: In a radio communication system, an electronic component for high frequency power amplifier carries out the detection of output level, required for feedback control of the output power of a high frequency power amplification circuit, by current detection. The electronic component has an error amplifier. The error amplifier compares an output level detection signal with an output level instruction signal, and generates a signal for controlling the gain of the high frequency power amplification circuit according to the difference between them. For the error amplifier, a low-pass amplification circuit is used. The amplification circuit is provided with, between its output terminal and its inverting input terminal, a phase compensation circuit. The phase compensation circuit comprises a resistance element, and another resistance element and a capacitive element in series connected in parallel with the resistance element.

Abstract: An upstream amplifier is integrated on a substrate with a digital-to-analog converter (DAC) to form an integrated circuit. In an embodiment, a low-pass filter is also integrated on the substrate. The output signal level of the upstream amplifier is controllable. In embodiments, fine adjustments are made to the output signal level of the upstream amplifier by varying a bias current of the DAC. A software control bit is used to switch between a power-on mode of operation and a power-down mode of operation. The upstream amplifier transmits in a burst mode. The power consumption of the upstream amplifier scales with the amplifier's output signal level. A high degree of matching is attained between the positive and negative paths of the upstream amplifier. This provides high immunity from common-mode disturbances such as substrate noise, clock spurs, and glitches caused by a gain change.

Abstract: Cascode bias structures are provided which enhance control of cascode biases over disturbing effects such as temperature and process variations. Because this enhanced control stabilizes the biases over these disturbing effects, the biases can be reduced to thereby expand the cascode's dynamic range and yet assure that the cascode transistors continue to operate in their proper transistor regions.

Abstract: A method of operating an amplifier, for example, in a wireless radio transceiver, including monitoring a characteristic of the amplifier during an operating interval of the amplifier, for example, during a transmission burst, providing an open-loop control signal to the amplifier during a subsequent operating interval of the amplifier wherein the open-loop control signal based on the characteristic monitored during a previous operating interval. In one embodiment, the corrected control signals are stored in a look-up table (510) that is updated based on the changes in load impedance.

Abstract: An integrated circuit device includes a semiconductor amplification element and a bias circuit for applying a bias voltage to the semiconductor amplification element. A power source of the bias circuit is connected to a power source of the semiconductor amplification element via a semiconductor element such that idle current of the semiconductor amplification element is changed in response to a change of a supply voltage of the semiconductor amplification element.

Abstract: A method and apparatus for an amplifier, such as a radio frequency amplifier embodied as an integrated circuit is disclosed. Embodiments provide for a wide range of operating powers with good energy efficiency at many power levels. Resonant components act to provide consistent operating parameters over the wide range of power levels used. The invention may operate in the microwave region or at other RFs.

Abstract: An adaptive bias circuit is provided for an amplifier module including a RF power amplifier for amplifying an input signal to generate an output signal, wherein the bias circuit receives the input signal to adjust a driving current to control a quiescent current of the RF power amplifier. The adaptive bias circuit includes means for providing the driving current to the bias circuit and means for drawing a bypass current from the providing means to reduce the driving current in response to the input signal, wherein the quiescent current is reduced when the driving current is reduced and the bypass current increases when the input signal is reduced.