| Entries |
| Document | Title | Date |
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| 20080197930 | Digital Amplifier - Recently, the use of class D audio amplifiers has become more and more widespread. In contrast to the generally employed class A-B linear amplification technology, class D allows for improved efficiency. However, the class D principle is known for its poor distortion characteristics. According to the present invention, a digital amplifier is provided for converting an input signal to a power output. The digital amplifier according to the present invention comprises a supply ripple pre-compensation circuit for compensating voltage ripples on a supply voltage supplied to bridge circuits of the digital amplifier on the basis of the input signal. By this, supply ripples in the supply voltage supplied to the bridge which have been found to cause a major part of the distortions in the output signal of the digital amplifier may be compensated. | 08-21-2008 |
| 20080211583 | SYSTEM AND METHOD FOR DYNAMIC DRAIN VOLTAGE ADJUSTMENT TO CONTROL LINEARITY, OUTPUT POWER, AND EFFICIENCY IN RF POWER AMPLIFIERS - A system and method for dynamic adjustment of drain or collector voltage of a power amplifier (PA), including a PA having a voltage input, a temperature sensor measuring ambient temperature of the PA, and an adaptive PA control processor that dynamically changes the input voltage based on the ambient temperature, achieving a desired peak power when the system is subjected to high temperatures. In a further embodiment, a power sensor measures output power of the PA, and the control processor dynamically changes the voltage based on output power when the system serves a large cell in a mobile communication infrastructure employing high power. In a further embodiment, a multistage PA and method include amplifier stages having drain or collector voltage inputs, wherein a voltage applied to the inputs are set so as to be proportional to the peak power requirements of each stage, enhancing overall efficiency. | 09-04-2008 |
| 20080211584 | Cross-differential amplifier - A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches. | 09-04-2008 |
| 20080252380 | Power Supply System - A power supply system comprises a parallel arrangement of a linear amplifier (LA) and a DC-DC converter (CO). An output of the linear amplifier (LA) is directly coupled to a load (LO) for supplying a first current (II) to the load (LO). The DC-DC converter (CO) has a converter output coupled to the load (LO) for supplying a second current ( | 10-16-2008 |
| 20080272848 | Nested transimpedance amplifier - A nested transimpedance amplifier (TIA) circuit comprises a zero-order TIA having an input and an output. A first operational amplifier (opamp) has an output and an input that communicates with said output of said zero-order TIA. A first power supply input applies a first voltage to the zero-order TIA. A second power supply input receives a second voltage. A charge pump module develops a third voltage based on the first voltage and the second voltage, wherein the third voltage is applied to the opamp. | 11-06-2008 |
| 20080290949 | APPARATUS AND METHOD FOR ASYMMETRIC CHARGE PUMP FOR AN AUDIO AMPLIFIER - An audio amplifier with an integrated asymmetric charge pump is provided. The audio amplifier receives VDD and VSS as power supply signals. The integrated charge pump is arranged to provide VSS from VDD, such that VSS is a negative voltage that is lower in magnitude than VDD. | 11-27-2008 |
| 20080290950 | SEMICONDUCTOR INTEGRATED CIRCUIT - The semiconductor integrated circuit includes a constant voltage regulator | 11-27-2008 |
| 20090002074 | Power Supply Control Circuit - The present invention is to provide a power supply control circuit that can effectively eliminate voltage distortion of an input signal during signal amplification. A power supply control circuit which controls a power supply voltage of a direct-current power source at a constant level and supplies the power supply voltage to an amplification circuit performing a differential operation alternately in accordance with a signal level of an input signal includes: a first transistor whose collector is connected to the direct-current power source and emitter is connected to the amplification circuit, for outputting a current; an error amplifier whose output port is connected to a base of the first transistor, for performing feedback control to hold a difference between a predetermined reference potential and a potential at the emitter of the first transistor at a constant level; and a second transistor whose emitter and base are mutually connected to the first transistor and collector is grounded, for absorbing a current. | 01-01-2009 |
| 20090002075 | AMPLIFIER WITH CONFIGURABLE DC-COUPLED OR AC-COUPLED OUTPUT - A multi-mode amplifier with configurable DC-coupled or AC-coupled output is described. In one design, the multi-mode amplifier includes an amplifier and at least one DC level shifting circuit. The amplifier receives and amplifies an input signal and provides an output signal that is suitable for DC coupling to a load in a DC-coupled mode and for AC coupling to the load in an AC-coupled mode. The at least one DC level shifting circuit performs DC level shifting for at least one (e.g., input and/or output) common-mode voltage of the amplifier and is controlled based on whether the amplifier is operating in the DC-coupled or AC-coupled mode. The amplifier operates between V | 01-01-2009 |
| 20090058533 | Voltage generating apparatus and methods - The invention provides a voltage generating apparatus for powering at least one amplifier. The voltage generating apparatus comprises a voltage source, a switched capacitor voltage converter and a voltage detector. The voltage source supplies a first voltage to a positive voltage input terminal of the at least one amplifier. The first voltage is a positive DC voltage. The switched capacitor voltage converter is coupled to the voltage source for outputting an output voltage to a negative voltage input terminal of the at least one amplifier according to the first voltage and a predetermined voltage. The output voltage is a negative DC voltage. The voltage detector is coupled to the switched capacitor voltage converter for determining a switching frequency corresponding to the predetermined voltage according to the output voltage. The switched capacitor voltage converter increases the output voltage when the switching frequency is decreased and decreases the output voltage when the switching frequency is increased. | 03-05-2009 |
| 20090091394 | DEVICE TO GENERATE A MODULATED ELECTRICAL RADIO-FREQUENCY SIGNAL FOR A MAGNETIC RESONANCE APPLICATION - A device for generation a modulated electrical radio-frequency signal for a magnetic resonance application has a phase modulator that generates a phase-modulated radio-frequency base signal, an amplitude modulator that generates an amplitude-modulated supply voltage, and a non-linear transmission output stage that, to supply the radio-frequency base signal, is connected via a signal input with the phase modulator and, to feed in the supply voltage, is connected via a supply voltage input with the amplitude modulator. The amplitude modulator includes at least two switching power supplies connected in parallel and clocked phase-offset relative to one another. | 04-09-2009 |
| 20090096531 | RF POWER AMPLIFIER APPARATUS AND POWER SUPPLY CIRCUIT FOR CONTROLLING-POWER SUPPLY VOLTAGE TO RF POWER AMPLIFIER - The RF power amplifier apparatus has an RF power amplifier RFPA and a power-supply circuit Pwr_Cnt. The power-supply circuit controls the level of a source voltage V | 04-16-2009 |
| 20090115531 | EFFICIENT POWER AMPLIFIER - A dynamic power supply for N amplifiers includes first and second power boost circuits which temporarily boost the positive or negative power supply rail, respectively. A control circuit monitors amplifier output signal levels and provides power boost control signals to the power boost circuits, which temporarily raise the positive supply voltage above the nominal voltage level in tandem with the highest output signal from the N amplifiers and lower the negative supply voltage below the nominal voltage level in tandem with the lowest output signal level from the N amplifiers. The power boost circuits each may be coupled to a reservoir capacitor from which current is drawn to provide the power boost. When inactive, the reservoir capacitors charge up from the respective power supply rails. The dynamic power supply is well suited for audio amplification systems. | 05-07-2009 |
| 20090153250 | METHOD AND SYSTEM FOR SCALING SUPPLY, DEVICE SIZE, AND LOAD OF A POWER AMPLIFIER - Aspects of a method and system for scaling supply, device size, and load of a power amplifier (PA) are provided. In this regard parameters of a PA, and a voltage, a current, and/or a load of the PA may be configured based on a determined amplitude of a baseband signal and based on a transmit power of the PA. In this regard, the PA may be configured by configuring device size of and/or selecting one or more transistors within the PA. The load may be a transformer and may be configured by adjusting a windings ratio. The PA may comprise one or more differential pairs. In this regard, device size of the differential pair(s) may be configured based on the determined amplitude of the baseband signal and based on a transmit power of the PA. | 06-18-2009 |
| 20090278607 | Power Supply Device For Driving An Amplifier - A power supply device for driving first and second amplifiers includes a first power generator, a second power generator, a charge pump and a control unit. The first power generator provides a first voltage for first power reception ends of the first and second amplifiers. The second power generator provides a second voltage. The charge pump is coupled between the second power generator and a second power reception end of the first amplifier and between the second power generator and a second power reception end of the second amplifier, and is used for generating a third voltage for the first and second amplifiers according to the second voltage. The control unit is coupled to the second power generator and is used for controlling the second power generator, so as to adjust the second voltage to make the third voltage equal to a multiple of the first voltage. | 11-12-2009 |
| 20090278608 | Power Supply Device for Driving an Amplifier - A power supply device for driving an amplifier includes a power generator for providing a first voltage for a first power reception end of the amplifier, a power conversion unit coupled to the power generator, for converting the first voltage into a second voltage, a charge pump coupled between the power conversion unit and a second power reception end of the amplifier, for generating a third voltage for the amplifier according to the second voltage, and a control unit coupled to the power conversion unit, for controlling the power conversion unit, so as to adjust the second voltage to make the third voltage equal to a specific multiple of the first voltage. | 11-12-2009 |
| 20090278609 | Supply control for multiple power modes of a power amplifier - In one embodiment, the present invention includes an apparatus having at least two gain stages to receive incoming signals and to output amplified signals, along with multiple regulators. More specifically, a linear regulator can be coupled to the first gain stage to provide a first regulated voltage to the first gain stage, and a switching regulator coupled to the second gain stage to provide a second regulated voltage to the second gain stage. | 11-12-2009 |
| 20090289720 | High-Efficiency Envelope Tracking Systems and Methods for Radio Frequency Power Amplifiers - High-efficiency envelope tracking (ET) methods and apparatus for dynamically controlling power supplied to radio frequency power amplifiers (RFPAs). An exemplary ET circuit includes a switch-mode converter coupled in parallel with a split-path linear regulator. The switch-mode converter is configured to generally track an input envelope signal Venv and supply the current needs of a load (e.g., an RFPA). The split-path linear regulator compensates for inaccurate envelope tracking by sourcing or sinking current to the load via a main current path. A current sense path connected in parallel with the main current path includes a current sense resistor used by a hysteresis comparator to control the switching of the switch-mode converter. The split-path linear regulator is configured so that current flowing in the current sense path is a lower, scaled version of the current flowing in the main current path. | 11-26-2009 |
| 20090302950 | SINGLE INPUT DUAL OUTPUT VOLTAGE POWER SUPPLY AND METHOD THEREFOR - In one embodiment, a power supply controller is configured to form both positive and negative supply voltages from a single input voltage so the maximum differential voltage across a load that uses the positive and negative supply voltages is no greater than the maximum value of the input voltage | 12-10-2009 |
| 20100013561 | ANTI-POP CIRCUITS AND METHODS FOR AUDIO AMPLIFIERS USING VARIABLE RESISTORS - Anti-pop circuits are provided for an audio amplifier that uses a power supply voltage and a ground voltage to drive a load with an audio signal that is centered about a virtual analog ground. These anti-pop circuits include a variable resistor and a capacitor that are connected to the audio amplifier to provide a low pass filter. The variable resistor has resistance that varies in response to a voltage level of the virtual analog ground, such as a difference between a voltage level of the power supply voltage and the voltage level of the virtual analog ground. The variable resistor may be a field effect transistor having a gate that is responsive to the differences between the voltage level of the power supply voltage and the voltage level of the virtual analog ground. The capacitor may be a field effect transistor, as well. Related methods are also described. | 01-21-2010 |
| 20100097148 | Headphone Amplifier Circuit - A class G headphone amplifier circuit with improved power efficiency and low EMI. It may use an automatic signal level detector to detect the signal level of incoming signals and determine positive and negative power supplies for headphone amplifiers accordingly. A voltage generator may generate pairs of differential output voltages at a plurality of amplitude steps, and supply to headphone amplifiers the pair with the amplitude determined by the automatic signal level detector. As a result, headphone amplifiers are biased according to the input signal level, and the multiple voltage rails may improve power efficiency and avoid clipping. | 04-22-2010 |
| 20100141345 | AMPLIFIER SYSTEM WITH DYNAMICALLY-ADJUSTED SUPPLY VOLTAGE - An amplifier system may include an output stage configured to provide an amplified output signal at an output thereof based on an input signal, the output stage being connected between first and second supply voltages. A dynamic power supply control system provides the first and second supply voltages, the dynamic power supply being configured to adjust the first and second supply voltages as a function of the input signal such that a difference between the first and second supply voltages remains substantially constant. | 06-10-2010 |
| 20100164630 | Adaptive signal-feed-forward circuit and method for reducing amplifier power without signal distortion - Digital amplifying circuitry delays a digital data signal (IN | 07-01-2010 |
| 20100164631 | ELECTRONIC SYSTEM HAVING COMMON MODE VOLTAGE RANGE ENHANCEMENT - An electronic system generates at least one floating supply voltage, wherein during operation of the circuit the floating supply voltage tracks a common mode voltage of first and second differential input signals. By tracking the common mode voltage, in at least one embodiment, the floating supply voltage adjusts as the common mode voltage changes. Thus, the floating supply voltages can be based upon the peak-to-peak values of the first and second output signals without factoring in the common mode voltage. In at least one embodiment, the electronic system provides the floating supply voltages to an amplifier. The amplifier amplifies the first and second differential input signals and generates differential output signals. A differential sampling circuit samples the differential output signals to cancel the common mode voltage from the differential output signals. In at least one embodiment, an analog-to-digital converter converts the sampled differential output signals into a digital output signal. | 07-01-2010 |
| 20100194479 | AMPLIFIER CIRCUIT AND METHODS OF OPERATION THEREOF - A signal amplifying circuit and associated methods and apparatuses, the circuit comprising: a signal path extending from an input terminal to an output terminal, a gain controller arranged to control the gain applied along the signal path in response to a control signal; an output stage within the signal path for generating the output signal, the output stage having a gain that is substantially independent of its supply voltage, and a variable voltage power supply comprising a charge pump for providing positive and negative output voltages, the charge pump comprising a network of switches that is operable in a number of different states and a controller for operating the switches in a sequence of the states so as to generate positive and negative output voltages together spanning a voltage approximately equal to the input voltage. | 08-05-2010 |
| 20100264992 | AMPLIFYING CIRCUIT AND AMPLIFYING METHOD - An amplifying circuit includes: a waveform modifying unit which changes the signal value in the second section in such a manner so as to reduce the difference between the signal strength of a DC component of the input signal and the limit value that limits the variation range of the signal value in the first section; a DC component removing unit which removes the DC component of the input signal after the input signal has been modified by the waveform modifying unit; and an amplifying unit which amplifies the input signal whose DC component has been removed. | 10-21-2010 |
| 20100289586 | METHOD FOR OBTAINING FIELD STRENGTH INFORMATION - A method for obtaining field strength information from a received electromagnetic signal by a receiver unit, in which an input voltage is generated for an operational amplifier from the received signal in the receiver unit by an input resistance and an output voltage is generated by the operational amplifier by a fixed amplification factor. The input voltage is changed until the output voltage lies within a predefined interval that includes the value of the reference voltage, and hereby the input voltage is tapped at a divider node of a voltage divider and to adjust the output voltage to the reference voltage the gate voltage of the MOS transistor, operating within a nonlinear range, and connected to the divider node is changed in such a way that the forward resistance of the MOS transistor is changed substantially logarithmically and the field strength value received by the receiver unit is determined from a comparison of the value of the present gate voltage with the quantities assigned to the gate voltage values in a memory. | 11-18-2010 |
| 20100321115 | Class-G Line Driver Control Signal - An apparatus comprising an input, a control signal generator coupled to the input and having a control signal generator output, and an amplifier coupled to the control signal generator output, wherein a voltage supplied to the amplifier is switched based on the control signal generator output, and wherein the control signal generator output is based on a data signal in the input. Also included is an apparatus comprising circuitry configured to implement a method comprising detecting an incoming signal, calculating a derivative of the incoming signal, estimating a future incoming signal based on the derivative of the incoming signal and a time step, and providing the estimated future incoming signal to switch between a first supply voltage and a second supply voltage prior to or concurrent with an arrival of the future incoming signal at the switch, wherein the incoming signal and the future incoming signal are analog signals. | 12-23-2010 |
| 20100321116 | METHOD AND APPARATUS FOR CONTROLLING POWER SUPPLY OF AUDIO AMPLIFIER - A method of controlling power supply voltage of an audio amplifier delays an input audio signal; estimates, with a digital signal processor, an audio output level of the delayed input audio signal based on correlations between the delayed input audio signal level and audio level change factors; sets a value of power supply voltage supplied to a power switching circuit unit in correspondence with the estimated audio output level prior to outputting the delayed input audio signal on which the estimated audio output level is based; and amplifies the delayed audio input signal to provide an audio output signal by variably controlling the power supply voltage supplied to the power switching circuit unit according to the set value of power supply voltage. | 12-23-2010 |
| 20100327979 | Current Detection Apparatus and Control System Using the Same - A highly accurate current detection apparatus is realized in a one-chip LSI. An end of a current detector is connected to an analog power supply (VACC) or a virtual analog ground potential (VAG) of a voltage amplifier and an A/D converter, and a predetermined voltage is supplied between the voltage amplifier and the virtual ground potential (VAG) by a power supply. | 12-30-2010 |
| 20110018640 | TRANSMITTER UTILIZING A DUTY CYCLE ENVELOPE REDUCTION AND RESTORATION MODULATOR - A broad power band transmitter utilizing a duty cycle modulator achieves 80dB of power range for 3G signals. The present invention greatly improves the efficiency of transmitters used in mobile phones, for example, by using the duty cycle modulator during medium and low power levels of the transmitting power amplifier. The power amplifier operates in three different modes based upon the amplifier power level selected. The power amplifier operates in an EER mode during high power levels, in a DCM ERR mode during medium power levels, and in a DCM mode during low power levels. | 01-27-2011 |
| 20110032038 | RF POWER AMPLIFIER APPARATUS AND POWER SUPPLY CIRCUIT FOR CONTROLLING POWER-SUPPLY VOLTAGE TO RF POWER AMPLIFIER - The RF power amplifier apparatus has an RF power amplifier and a power-supply circuit. The power-supply circuit controls the level of a source voltage supplied to the RF power amplifier in response to the level of a power-control signal. A sensing resistance produces a sense signal Vsen corresponding to a source current with respect to a source voltage. The current-control unit controls the source current I | 02-10-2011 |
| 20110032039 | EFFICIENT POWER AMPLIFIER - A dynamic power supply for N amplifiers includes first and second power boost circuits which temporarily boost the positive or negative power supply rail, respectively. A control circuit monitors amplifier output signal levels and provides power boost control signals to the power boost circuits, which temporarily raise the positive supply voltage above the nominal voltage level in tandem with the highest output signal from the N amplifiers and lower the negative supply voltage below the nominal voltage level in tandem with the lowest output signal level from the N amplifiers. The power boost circuits each may be coupled to a reservoir capacitor from which current is drawn to provide the power boost. When inactive, the reservoir capacitors charge up from the respective power supply rails. The dynamic power supply is well suited for audio amplification systems. | 02-10-2011 |
| 20110050349 | BOOSTED-RAIL AMPLIFIER - An amplifier device including an amplifier having an input for receiving an audio input signal and an output for sending an output signal to a load. A boosted-rail circuit is connected to a power source and has a single boosted rail connected to the BTL amplifier. Also, a common-mode circuit is coupled to the boosted-rail circuit and the BTL amplifier. The common-mode circuit sends a common-mode signal to the BTL amplifier that will dynamically track the output voltage supplied from the boosted-rail circuit to the BTL amplifier. In operation, the boosted-rail circuit reacts to the BTL amplifier and switches from a non-boost mode to a boost mode to increase the output voltage supplied to the BTL when the BTL amplifier requires additional voltage. | 03-03-2011 |
| 20110095829 | HEADPHONE AMPLIFIER CIRCUIT - A class G headphone amplifier circuit with improved power efficiency and low EMI. It may use an automatic signal level detector to detect the signal level of incoming signals and determine positive and negative power supplies for headphone amplifiers accordingly. A voltage generator may generate pairs of differential output voltages at a plurality of amplitude steps, and supply to headphone amplifiers the pair with the amplitude determined by the automatic signal level detector. As a result, headphone amplifiers are biased according to the input signal level, and the multiple voltage rails may improve power efficiency and avoid clipping. | 04-28-2011 |
| 20110102089 | SEMICONDUCTOR DEVICE AND METHOD OF CONTROLLING THE SAME - When overdriving a first power supply voltage supplied to a sense amplifier, a line for the first power supply voltage and a line for a second power supply voltage which is higher than the first power supply voltage are connected to each other by a first transistor, thereby boosting the first power supply voltage. When the first power supply voltage drops upon activation of the sense amplifier, the line for the first power supply voltage and the line for the second power supply voltage are connected to each other by a second transistor, thereby increasing the current supply capability. The first transistor and the second transistor are fully driven to operate as switches. | 05-05-2011 |
| 20110115563 | AMPLIFIER CIRCUIT AND METHODS OF OPERATION THEREOF - A signal amplifying circuit and associated methods and apparatuses, the circuit comprising: a signal path extending from an input terminal to an output terminal, a gain controller arranged to control the gain applied along the signal path in response to a control signal; an output stage within the signal path for generating the output signal, the output stage having a gain that is substantially independent of its supply voltage, and a variable voltage power supply comprising a charge pump for providing positive and negative output voltages, the charge pump comprising a network of switches that is operable in a number of different states and a controller for operating the switches in a sequence of the states so as to generate positive and negative output voltages together spanning a voltage approximately equal to the input voltage. | 05-19-2011 |
| 20110221533 | AMPLIFIER CIRCUIT AND METHOD OF AMPLIFYING A SIGNAL IN AN AMPLIFIER CIRCUIT - There is provided an amplifier circuit, comprising: an input, for receiving an input signal to be amplified; a power amplifier, for amplifying the input signal; a switched power supply, having a switching frequency, for providing at least one supply voltage to the power amplifier; and a dither block, for dithering the switching frequency of the switched power supply. The dither block is controlled based on the input signal. Another aspect of the invention involves using first and second switches, each having different capacitances and resistances, and using the first or second switch depending on the input signal or volume signal. Another aspect of the invention involves controlling a bias signal provided to one or more components in the signal path based on the input signal or volume signal. | 09-15-2011 |
| 20110234323 | AMPLIFICATION CONTROL CIRCUIT - There is provided an amplification control circuit that can adjust the amount of current being supplied to an amplifier according to a reference signal set beforehand. An amplification control circuit according to an aspect of the invention may include: a power supply section supplying a DC power set beforehand to at least one amplifier according to a reference signal set beforehand; a current control section detecting a current being supplied from the power supply section according to a ratio set beforehand and controlling the amount of current being supplied to the at least one amplifier from the power supply section; and a current adjustment section adjusting a level of the current being controlled by the current control section in order to increase or decrease the amount of current being supplied to the at least one amplifier from the power supply section. | 09-29-2011 |
| 20110285468 | Pre-amplifier - A pre-amplifier comprises at least two PMOS transistors operated as source followers and two NMOS transistors operated as amplifiers, or, two NMOS transistors operated as source followers and two PMOS transistors operated as amplifiers to raise or reduce the voltage of input signals and at least four current sources with the same current value which can be adjusted according to the output load of the pre-amplifier. The MOS transistors have the same transconductance so that the minimum differential voltage can be attained. Since the differential signals change alternately, MOS transistors will switch among the three working status: cut-off, saturation and linear region. Because of the cut-off and linear region, the present invention can achieve the very low power consumption less than one third of the conventional one. | 11-24-2011 |
| 20110298546 | SATURATION PROTECTION OF A REGULATED VOLTAGE - A system for preventing power amplifier supply voltage saturation includes a multiple stage voltage regulator configured to provide a regulated voltage, a power amplifier configured to receive the regulated voltage, and a saturation protection circuit configured to apply a current into a first stage of the multiple stage voltage regulator when the regulated voltage reaches a reference voltage, the applied current causing a subsequent stage of the multiple stage voltage regulator to prevent the regulated voltage from exceeding the reference voltage. | 12-08-2011 |
| 20120025917 | Efficient amplification stage - This is disclosed an amplification stage including a first amplifier stage, a second amplifier stage, and a power supply unit, in which the output of the first stage provides the input to the second stage, and the power supply unit provides a power supply for both amplifier stages, wherein the voltage of the power supply is continuously varied in dependence of the amplitude of the signal being amplified. | 02-02-2012 |
| 20120044023 | Apparatus and Method for a Smooth Powerup of a Reference Signal - A circuit for providing a reference voltage can be widely used in audio applications. However, at startup an abrupt start in the reference signal can cause undesirable audible artifacts. A circuit employing feedback of a reference voltage to control the charging of a capacitor which provides the reference voltage can be used to provide a smooth startup to the reference voltage. The circuit contains a differential pair for steering a fixed current source from one path to another as the reference voltage increases. The steered current can then be mirrored into one or more current mirrors where the newly mirrored current can be squeezed to zero when the difference between a desired reference voltage and the reference voltage approaches zero. This newly mirrored current can be used to charge a capacitor which is used to provide the reference voltage. | 02-23-2012 |
| 20120062323 | Radio-Frequency Power Amplifier with Fast Envelope Tracking - A radio-frequency power amplifier with envelope tracking, comprising: a power RF amplifying device for amplifying a RF signal; and a switching DC/DC converter, comprising a switching device and a rectifying device, for providing said power RF amplifying device with a DC power supply at a voltage level proportional to an envelope of said RF signal; wherein said switching device is a RF power transistor; characterized in that said rectifying device, and preferably also said power RF amplifying device, is also a transistor of a same technology, connected as a two-terminal device. Preferably, said power RF amplifying device is also a transistor of said same technology. A low-pass filter can also be provided for reducing the bandwidth of the envelope signal on which the PWM signal driving the DC/DC converter depends. | 03-15-2012 |
| 20120081183 | Current Saving by Reduced Modulation Code and Selective Gating of RF Signal - A polar modulation power amplifier employs both thermometer coded and binary coded amplitude modulation data. The thermometer coded amplitude modulation data selectively activates one or more equally weighted power amplifier cells. The binary coded amplitude modulation data selectively activates one or more binary weighted power amplifier cells. When less than full output power is required and the MSBs of the amplitude modulation data are zero (reducing output power at the expense of quantization noise), the power dissipated by RF signal buffers for the unused power amplifier cells corresponding to the MSBs is substantially reduced by gating off the RF signal upstream of the buffers. | 04-05-2012 |
| 20120098601 | AMPLIFYING CIRCUIT - When an output voltage from the amplifying circuit includes a positive DC voltage, an electric current continuously flows in a power source voltage, a load, and a reference voltage in this order. As a result, the reference voltage increases so as to be a first threshold voltage or more. The detecting section detects that the reference voltage is the first threshold voltage or more. When the output voltage from the amplifying circuit includes a negative DC voltage, an electric current continuously flows in the reference voltage, the load, a grounding potential in this order. As a result, the reference voltage reduces so as to be a second threshold voltage or less. The detecting section detects that the reference voltage is the second threshold voltage or less. | 04-26-2012 |
| 20120098602 | POWER CONSUMPTION CONTROL CIRCUIT, AMPLIFIER CIRCUIT AND POWER CONSUMPTION CONTROL METHOD - Provided is a power consumption control circuit, an amplifier circuit and a power consumption control method which control the power consumption associated with an amplification action in real time. | 04-26-2012 |
| 20120126899 | Power Amplifier with Stabilising Network - A power amplifier circuit comprising a transistor for receiving a signal to be amplified at an input and for outputting an amplified signal at an output; a modulated power supply connected to the transistor output; and a resistive element connected at the transistor output such that a low impedance is maintained at the transistor output across a range of operational frequencies. | 05-24-2012 |
| 20120169425 | DC-DC CONVERTER SWITCHING TRANSISTOR CURRENT MEASUREMENT TECHNIQUE - A method is described comprising conducting a first current through a switching transistor. The method also comprises conducting a second current through a pair of transistors whose conductive channels are coupled in series with respect to each other and are together coupled in parallel across the switching transistor's conductive channel. The second current is less than and proportional to the first current. | 07-05-2012 |
| 20120176200 | CROSS-DIFFERENTIAL AMPLIFIER - A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches. | 07-12-2012 |
| 20120223777 | RF Power Amplifier Circuit With Mismatch Tolerance - A radio frequency (RF) power amplifier system adjusts the supply voltage provided to a power amplifier (PA) adaptively, responsive to the measured or estimated power of the RF output signal of the PA. The RF PA system includes a power amplifier (PA) which receives and amplifies an RF input signal to generate an RF output signal at a level suitable for transmission to an antenna. A PA supply voltage controller generates a supply voltage control signal, which is used to control the supply voltage to the final stage of the PA. The supply voltage control signal is generated responsive to the measured or estimated power of the PA RF output signal, and also may be responsive to a parameter indicative of impedance mismatch experienced at the PA output. By controlling this supply voltage to the RF PA, the efficiency of the PA is improved. | 09-06-2012 |
| 20120242413 | AMPLIFIER CIRCUIT AND METHOD OF AMPLIFYING A SIGNAL IN AN AMPLIFIER CIRCUIT - An amplifier circuit, comprising: an input, for receiving an input signal to be amplified; a power amplifier, for amplifying the input signal; a switched power supply, having a switching frequency, for providing at least one supply voltage to the power amplifier; and a dither block, for dithering the switching frequency of the switched power supply. The dither block is controlled based on the input signal. Another aspect of the invention involves using first and second switches, each having different capacitances and resistances, and using the first or second switch depending on the input signal or volume signal. Another aspect of the invention involves controlling a bias signal provided to one or more components in the signal path based on the input signal or volume signal. | 09-27-2012 |
| 20120249247 | Front-End Circuit of Low Supply-Voltage Memory Interface Receiver - A circuit includes a reference voltage generator configured to generate a first reference voltage and a second reference voltage, wherein the first reference voltage is higher than a half of a positive power supply voltage, and the second reference voltage is lower than the half of the positive power supply voltage. An n-type differential amplifier includes a first and a second NMOS transistor, wherein a gate of the first NMOS transistor is coupled to an input node, and a gate of the second NMOS transistor is configured to receive the first reference voltage. A p-type differential amplifier is operated by the positive supply voltage and includes a first and a second PMOS transistor. A gate of the first PMOS transistor is coupled to the input node, and a gate of the second PMOS transistor is configured to receive the second reference voltage. | 10-04-2012 |
| 20120274405 | AMPLIFIER - An amplifier including: an output stage having two first power supply terminals capable of receiving a first voltage defined by first positive and negative variable potentials with respect to a reference potential; and a circuit for controlling the current in transistors of the output stage with a reference value, wherein the output stage includes a first and a second MOS transistors in series between the first two terminals, the junction point of this series association defining an output terminal of the amplifier; the control circuit includes two measurement MOS transistors having their respective sources and gates coupled to the respective sources and gates of the first and second transistors of the output stage; at least one control branch, comprising transistors in series between two terminals of application of a second voltage, defines nodes connected to the gates of the output transistors, said second voltage being greater than the first one. | 11-01-2012 |
| 20120313712 | APPARATUS AND METHOD FOR A SMOOTH POWERUP OF A REFERENCE SIGNAL - A circuit for providing a reference voltage can be widely used in audio applications. However, at startup an abrupt start in the reference signal can cause undesirable audible artifacts. A circuit employing feedback of a reference voltage to control the charging of a capacitor which provides the reference voltage can be used to provide a smooth startup to the reference voltage. The circuit contains a differential pair for steering a fixed current source from one path to another as the reference voltage increases. The steered current can then be mirrored into one ore more current mirrors where the newly mirrored current can he squeezed to zero when the difference between a desired reference voltage and the reference voltage approaches zero. This newly mirrored current can he used to charge a capacitor which is used to provide the reference voltage. | 12-13-2012 |
| 20120313713 | Switching Power Supply - A power supply is disclosed herein. For example, the power supply can include a switching device and an aperture generator and control module. The switching device can be configured to down-convert an input voltage and pass the down-converted input voltage to an output voltage node. The aperture generator and control module can be configured to control the switching device. In response to a power efficiency of the power supply exceeding a predetermined threshold, the aperture generator and control module can deactivate the switching device and pass the input voltage to the output voltage node. | 12-13-2012 |
| 20130002359 | AMPLIFIER WITH HIGH POWER SUPPLY NOISE REJECTION - An amplifier with high power supply rejection is disclosed. In an exemplary implementation, an amplifier includes a first stage configured to receive a signal to be amplified, a second stage comprising an input transistor coupled to the first stage, and further comprising at least one additional transistor, and a voltage regulator configured to received a first supply voltage and generate a regulated supply voltage, the first supply voltage coupled to the at least one additional transistor, the regulated supply voltage coupled to the first stage and the input transistor of the second stage to improve power supply noise rejection of the apparatus. | 01-03-2013 |
| 20130027138 | AMPLIFIER CIRCUIT AND METHOD FOR SIGNAL SENSING - An amplifier circuit ( | 01-31-2013 |
| 20130033328 | EFFICIENT POWER AMPLIFIER - A dynamic power supply for N amplifiers includes first and second power boost circuits which temporarily boost the positive or negative power supply rail, respectively. A control circuit monitors amplifier output signal levels and provides power boost control signals to the power boost circuits, which temporarily raise the positive supply voltage above the nominal voltage level in tandem with the highest output signal from the N amplifiers and lower the negative supply voltage below the nominal voltage level in tandem with the lowest output signal level from the N amplifiers. The power boost circuits each may be coupled to a reservoir capacitor from which current is drawn to provide the power boost. When inactive, the reservoir capacitors charge up from the respective power supply rails. The dynamic power supply is well suited for audio amplification systems. | 02-07-2013 |
| 20130043953 | METHODS, CIRCUITS AND SYSTEMS FOR REGULATING THE OUTPUT POWER OF A TRANSMISSION SYSTEM - Disclosed are methods, circuits and systems for regulating the output power of a transmission system. There may be provided a power amplifier (“PA”) adapted to operate across a range of supply voltages. The PA may operate under different bias profiles. There may be provided power amplifier regulation circuitry which may include a PA bias profile generator adapted to generate one or more bias profiles, wherein a given bias profile is associated with a given bias signal for the PA. A bias profile associated with a given bias signal for a given PA may include one or more PA parameters or settings to be applied to the given PA when it is operating with the given bias signal. | 02-21-2013 |
| 20130057351 | Current-Voltage Converter Having a Current Reflector, Input Stage of an Amplifier and Corresponding Amplifier - This current-voltage converter( | 03-07-2013 |
| 20130063216 | POWER OFF DELAY CIRCUIT AND METHOD, AND AUDIO SYSTEM WITH POWER OFF DELAY - A power off delay circuit includes a switch connected between an external power input terminal and an internal power supply terminal, a capacitor connected to the internal power supply terminal, and a hysteresis comparator to switch the switch according to the voltages of the external power input terminal and the internal power supply terminal. During on-time of the switch, the external power input terminal is connected to the internal power supply terminal and the capacitor can be charged by the external power source. When the switch is off, the capacitor provides electric power for an internal circuit. Application of the power off delay circuit to an audio system may eliminate the turn-off pops of the audio system. | 03-14-2013 |
| 20130093521 | APPARATUS AND METHOD FOR INTERLEAVING SWITCHING IN POWER AMPLIFIER - An apparatus of a hybrid power modulator using interleaving switching is provided. The apparatus includes a linear switching unit for generating an output signal by comparing an envelope input signal and a feedback signal, an interleaving signal generator for generating an interleaving switching signal arranged not to supply the signal to input stages of P-type Metal-Oxide-Semiconductor (MOS) Field Effect Transistors (FETs) and N-type MOS FETs of power cells at the same time by comparing the output signal and a reference signal, and a switching amplifying unit for determining a level of the switching signal using the interleaving switching signal. Hence, the hybrid power modulator using the interleaving switching method in the envelope signal of the wide bandwidth maintains high efficiency and high linearity. In addition, the buck converter can use the single inductor by preventing the simultaneous on/off of the power cells. | 04-18-2013 |
| 20130127547 | EFFICIENT SUPPLY VOLTAGE - There is disclosed an arrangement comprising: a driver stage connected to receive an input signal and generate a drive signal; a transformer comprising: a first winding of a first side of the transformer, across which winding a voltage signal is developed in dependence on the drive signal; and a second winding of the first side of the transformer, coupled to the first winding, which exhibits across it a voltage signal related to the voltage across the first winding, by swingback; and a first controller for comparing the voltage exhibited in the second winding to a first threshold voltage, and for selecting a first or a second supply voltage for the arrangement in dependence on the comparison. | 05-23-2013 |
| 20130127548 | APPARATUS AND METHODS FOR VOLTAGE CONVERTERS - Apparatus and methods for voltage converters are provided. In one embodiment, a voltage conversion system includes a bypass circuit and a voltage converter including an inductor and a plurality of switches configured to control a current through the inductor. The bypass circuit includes a first p-type field effect transistor (PFET), a second PFET, a first n-type field effect transistor (NFET), and a second NFET. The first and second NFET transistors and the first and second PFET transistors are electrically connected between a first end and a second end of the inductor such that a source of the first PFET transistor and a drain of the first NFET transistor are electrically connected to the first end of the inductor and such that a drain of the second PFET transistor and a source of the second NFET transistor are electrically connected to the second end of the inductor. | 05-23-2013 |
| 20130141169 | LINEAR AMPLIFIER POWER SUPPLY MODULATION FOR ENVELOPE TRACKING - Circuitry, which includes a linear amplifier and a linear amplifier power supply, is disclosed. The linear amplifier at least partially provides an envelope power supply signal to a radio frequency (RF) power amplifier (PA) using a selected one of a group of linear amplifier supply voltages. The linear amplifier power supply provides at least one of the group of linear amplifier supply voltages. Selection of the selected one of the group of linear amplifier supply voltages is based on a desired voltage of the envelope power supply signal. | 06-06-2013 |
| 20130229235 | HIGH-FREQUENCY AMPLIFIER, AND HIGH-FREQUENCY MODULE AND WIRELESS TRANSCEIVER USING SAME - There are provided a high-frequency amplifier and a high-frequency module having a high efficiency for an extensive input modulated signal power, and base station/mobile wireless machines using the amplifier or the module. | 09-05-2013 |
| 20130241660 | Buck Up Power Converter - Generally, this disclosure provides an apparatus, method and system for DC-DC conversion. The apparatus may include a switch network including a first plurality of switches configured to operate in a Buck mode to generate an output voltage that is less than an input voltage, and a second plurality of switches configured to operate in an Up mode to generate an output voltage that is greater than the input voltage. The apparatus of this example may further include controller circuitry configured to generate control signals to control the conduction state of the first plurality of switches and the second plurality of switches based on a variable reference signal indicative of power demands from a load coupled to the switch network. | 09-19-2013 |
| 20130271225 | POWER MODULE FOR ENVELOPE TRACKING - A power module for envelope tracking includes a linear amplifier and a DC-to-DC (Direct Current to Direct Current) converter. The linear amplifier has a positive input terminal for receiving a first control signal, a negative input terminal, and an output terminal for outputting a first adaptive supply voltage, wherein the output terminal is fed back to the negative input terminal. The DC-to-DC converter receives a second control signal, and supplies a second adaptive supply voltage to the linear amplifier according to the second control signal. The first control signal is related to the second control signal. | 10-17-2013 |
| 20130285751 | ENHANCED PULSE FREQUENCY MODULATION (PFM) CONTROL MODE FOR SWITCHING REGULATORS - A variable supply rail generator is described. The variable supply rail generator includes a regulator configured to use an estimated load current for a power amplifier to optimize efficiency. The variable supply rail generator also includes a power amplifier controller. The power amplifier controller provides the estimated load current to the regulator. | 10-31-2013 |
| 20140077884 | HIGH VOLTAGE AMPLIFIERS AND METHODS - Some embodiments provide an amplifier apparatus, comprising: a plurality of amplifier transistor circuits coupled in series, wherein each of the plurality of amplifier transistor circuits comprises: a transistor, wherein the transistors of the plurality of amplifier transistor circuits are coupled in series; a transistor voltage control and drive circuit coupled with the corresponding transistor, wherein the transistor voltage control and drive circuit is configured to control and drive the corresponding transistor in accordance with received control signals and in parallel with the other of the plurality of amplifier transistor circuits; and isolation circuitry that isolates control of the transistor from control of the other of the amplifier transistor circuits; wherein the plurality of amplifier transistor circuits are configured to be controlled and driven in parallel relative to the control signals. | 03-20-2014 |
| 20140077885 | TWO MODE POWER CONVERTER FOR AUDIO AMPLIFIERS - A power converter with positive and negative supply rail outputs for feeding a single ended class D amplifier, the converter comprising a transformer arrangement, a supply pump reduction arrangement connected between the secondary windings and the positive and negative supply rail outputs, and a boost drive mode switching arrangement. A controller is adapted to control the power converter in a negate drive mode and a boost drive mode, wherein the output voltage in the boost mode is increased by means of the transformer and the boost drive mode switching arrangement. The output voltages on the positive and negative rails can be generated at two different output voltage levels without changing the duty cycle or dead time of the control signals. | 03-20-2014 |
| 20140085007 | CLASS-AB RADIO FREQUENCY AMPLIFIER FOR ENVELOPE DETECTOR - An envelope detector (ED) includes a voltage-mode ED core including parallel detection transistors for detecting a voltage envelope of a radio frequency (RF) signal input, the RF signal input including an output of a radio such as a cellular transmitter (TX). The ED further includes multiple voltage amplifiers positioned serially in gain stages between the TX output and the ED core to provide a total linear voltage range of the envelope detector. A final voltage amplifier of the multiple voltage amplifiers drives the ED core and includes a class-AB RF amplifier configured to operate within a full linear voltage range of the ED core. | 03-27-2014 |
| 20140085008 | ENVELOPE TRACKING SIGNAL GENERATOR INCORPORATING TRIM CELL - A novel and useful radio frequency (RF) front end module (FEM) circuit that provides high linearity and power efficiency and meets the requirements of modern wireless communication standards such as 802.11 WLAN, 3G and 4G cellular standards, Bluetooth, ZigBee, etc. The configuration of the FEM circuit permits the use of common, relatively low cost semiconductor fabrication techniques such as standard CMOS processes. The FEM circuit includes a power amplifier made up of one or more sub-amplifiers having high and low power circuits and whose outputs are combined to yield the total desired power gain. An integrated multi-tap transformer having primary and secondary windings arranged in a novel configuration provide efficient power combining and transfer to the antenna of the power generated by the individual sub-amplifiers. | 03-27-2014 |
| 20140118075 | SPUR CANCELLATION IN GSM-GPRS-EDGE POWER AMPLIFIERS WITH DC-DC CONVERTERS - A radio frequency (RF) power amplifier circuit with spur cancellation for GSM/GPRS/EDGE transceivers is disclosed. There is a power amplifier with an RF input, an RF output, and a voltage supply input. Additionally, there is an adjustable DC-DC converter with an input connected to a battery, an output connected to the voltage supply input of the power amplifier with a DC supply voltage signal generated thereby. A spur compensator generates an error control signal responsive to spurs in the DC supply voltage signal. The error control signal is applied to the RF input of the power amplifier. | 05-01-2014 |
| 20140132354 | Linearization Circuits And Methods For Multilevel Power Amplifier Systems - Circuits and methods for achieving high linearity, high efficiency power amplifiers, including digital predistortion (DPD) and pulse cancellation in switched-state RF power amplifier systems are described. | 05-15-2014 |
| 20140184339 | High Efficiency Output Stage Amplification for Radio Frequency (RF) Transmitters - Highly power efficient transmitter output stage designs are provided. In an embodiment, the probability density function (PDF) of an input signal is divided into a plurality of regions, and samples of the input signal are processed depending on the region of the PDF within which they fail. The PDF can be divided between an inner region corresponding to samples of the input signal that are within a predetermined amplitude range, and outer regions corresponding to samples of the input signal that are outside of the predetermined amplitude range. Samples of the input signal that fall in the inner region are processed by a class A biased amplifier and samples of the input signal that fall in the outer regions are processed by a class B biased amplifier. Output stage designs according to embodiments can be implemented as power amplifiers or power digital-to-analog converters (DACs). | 07-03-2014 |
| 20140203878 | APPARATUS AND METHODS FOR REDUCING CAPACITIVE LOADING OF A POWER AMPLIFIER SUPPLY CONTROL MODULE - Apparatus and methods for reducing capacitive loading of a power amplifier supply control module are disclosed. In one embodiment, a method of power supply control in a power amplifier system includes controlling a voltage level of a supply voltage using a supply control module, amplifying a first radio frequency (RF) signal using a first power amplifier module, amplifying a second RF signal using a second power amplifier module, delivering the supply voltage to a first supply input of the first power amplifier module through a first resonant circuit, and delivering the supply voltage to a second supply input of the second power amplifier module through a second resonant circuit. The first resonant circuit includes a first inductor and a first capacitor electrically connected in parallel, and the second resonant circuit includes a second inductor and a second capacitor electrically connected in parallel. | 07-24-2014 |
| 20140210559 | DYNAMIC HEADROOM FOR ENVELOPE TRACKING - Techniques for dynamically generating a headroom voltage for an envelope tracking system. In an aspect, an initial headroom voltage is updated when a signal from a power amplifier (PA) indicates that the PA headroom is insufficient. The initial headroom voltage may be updated to an operating headroom voltage that includes the initial voltage plus a deficiency voltage plus a margin. In this manner, the operating headroom voltage may be dynamically selected to minimize power consumption while still ensuring that the PA is linear. In a further aspect, a specific exemplary embodiment of a headroom voltage generator using a counter is described. | 07-31-2014 |
| 20140218117 | DCM and PFM Management - The present invention relates to a voltage regulating device comprising a power stage ( | 08-07-2014 |
| 20140232470 | High Efficiency Amplification - A radio frequency amplification stage comprising: an amplifier for receiving an input signal to be amplified and a power supply voltage; and a power supply voltage stage for supplying said power supply voltage, comprising: means for providing a reference signal representing the envelope of the input signal; means for selecting one of a plurality of supply voltage levels in dependence on the reference signal; and means for generating an adjusted selected power supply voltage, comprising an ac amplifier for amplifying a difference between the reference signal and one of the selected supply voltage level or the adjusted selected supply voltage level, and a summer for summing the amplified difference with the selected supply voltage to thereby generate the adjusted supply voltage. | 08-21-2014 |
| 20140240050 | POWER CIRCUIT - A power circuit includes a bridge circuit connected to a first node by which an output voltage is supplied to a load circuit including an amplifier containing a CMOS inverter, and configured to generate a current flowing in a first current channel and a current flowing in a second current channel in accordance with a voltage difference between the output voltage and a predetermined set voltage to be supplied to the load circuit, and a current amplifier configured to generate a current flowing in a third current channel to the load circuit in accordance with an input source voltage and a difference between the current flowing in the first current channel and the current flowing in the second current channel. The predetermined set voltage that is supplied to the load circuit achieves the smallest transconductance during normal operation of the amplifier. | 08-28-2014 |
| 20140240051 | Audio Amplifier Power Supply with Inherent Power Factor Correction - An audio amplifier is powered by a switch mode power supply optimized for audio applications. The power supply includes a rectifier circuit and a discontinuous mode multiphase isolated flyback power circuit and does not require a separate power factor correction stage. The discontinuous mode multiphase isolated flyback power circuit includes multiple isolated flyback converters operating synchronously to each convert a portion of the power and supply a phase-summed direct current voltage to the audio amplifier. | 08-28-2014 |
| 20140266468 | TRACKING POWER SUPPLY WITH INCREASED BOOST CAPABILITY - A tracking power supply for one or more amplifiers includes one or more cascaded sets of power boost circuits to temporarily boost the positive and/or negative power supply rail, respectively. Each power boost circuit may include a gain element and an energy source such as a capacitor or battery, and the power boost circuits are linked to provide a greater degree of voltage boost when needed. An optional control circuit monitors amplifier output signal levels, or separately amplified input signal levels, and provides power boost control signals to the power boost circuits, which temporarily raise or lower the positive and/or negative supply voltages above or below the nominal voltage rails in tandem with the highest and lowest output signals, respectively, from the amplifier(s). | 09-18-2014 |
| 20140285269 | High Efficiency Amplification - A radio frequency amplification stage comprising: an amplifier for receiving an input signal to be amplified and a power supply voltage; and a power supply voltage stage for supplying said power supply voltage, comprising: means for providing a reference signal representing the envelope of the input signal; means for selecting one of a plurality of supply voltage levels in dependence on the reference signal; and means for generating an adjusted selected power supply voltage, comprising an ac amplifier for amplifying a difference between the reference signal and one of the selected supply voltage level or the adjusted selected supply voltage level, and a summer for summing the amplified difference with the selected supply voltage to thereby generate the adjusted supply voltage. | 09-25-2014 |
| 20140306768 | OPERATIONAL AMPLIFIER CIRCUIT - An operational amplifier circuit including a main circuit, a compensation capacitor, a power circuit, and a set of switches is disclosed. The main circuit has an output terminal. The compensation capacitor has a first end connected to an internal node of the main circuit and a second end connected to the output terminal of the main circuit. The power circuit provides a current or a voltage as predetermined. The set of switches connects the power circuit to the compensation capacitor. When the main circuit is not in an output state, the set of switches is switched to allow the power circuit to provide the current or voltage to the compensation capacitor. When the main circuit is in the output state, the set of switches is switched to disconnect the power circuit from the compensation capacitor and allow the main circuit to return to an output circuit state and operate normally. | 10-16-2014 |
| 20140306769 | DUAL INSTANTANEOUS ENVELOPE TRACKING - Power supply circuitry, which includes a parallel amplifier and a parallel amplifier power supply, is disclosed. The power supply circuitry operates in either an average power tracking mode or an envelope tracking mode. The parallel amplifier power supply provides a parallel amplifier power supply signal. The parallel amplifier regulates an envelope power supply voltage based on an envelope power supply control signal using the parallel amplifier power supply signal, which provides power for amplification. During the envelope tracking mode, the envelope power supply voltage at least partially tracks an envelope of an RF transmit signal and the parallel amplifier power supply signal at least partially tracks the envelope power supply control signal. During the average power tracking mode, the envelope power supply voltage does not track the envelope of the RF transmit signal. | 10-16-2014 |
| 20140306770 | Adaptive Supply Voltage for a Power Amplifier - A signal-processing system has an amplifier that generates an amplified (RF) output signal based on an (RF) input signal. The amplifier receives a supply voltage that can be selectively set to an appropriate level between a lower power supply level and a higher power supply level. With one power supply permanently connected to the supply voltage node, a control unit executes software to toggle a supply switch to periodically connect and disconnect the other power supply thereby generating a weighted average value for the supply voltage between the two power supply levels. When a sudden and large increase occurs in the (input) power level, hardware-interrupt circuitry interrupts and supersedes the software-based control of the supply-voltage switch to quickly switch the supply voltage towards the higher power supply level. The hardware-interrupt circuitry handles such situations faster than the software-based control in order to prevent a limit violation of spectrum emission requirements. | 10-16-2014 |
| 20140327485 | POWER MODULE FOR ENVELOPE TRACKING - A power module at least includes an ET (Envelope Tracking) module. The ET module includes a buck converter, an inductor, and a capacitor. The buck converter is coupled to a work voltage. The buck converter has a first input terminal for receiving a first control signal, a second input terminal coupled to a supply node, and a buck output terminal The inductor is coupled between the buck output terminal of the buck converter and the supply node. The capacitor is coupled between the supply node and a ground voltage. The ET module is configured to supply a first adaptive supply voltage at the supply node. The first adaptive supply voltage is determined according to the first control signal. | 11-06-2014 |
| 20140340158 | REDUCING KICKBACK CURRENT TO POWER SUPPLY DURING CHARGE PUMP MODE TRANSITIONS - Kickback current from a charge pump to a power management integrated circuit (PMIC) may be reduced by dissipating charge from fly and hold capacitors during mode transitions. A switch may be placed in series between the charge pump and the PMIC to disconnect the charge pump and prevent kickback current from reaching the PMIC. Further, additional loads, as switches, may be coupled to the charge pump outputs to dissipate charge from the fly and hold capacitors. Additionally, a closed feedback loop may be used to monitor and discharge excess charge from the fly and hold capacitors during mode transitions. Furthermore, charge may be redistributed between the fly and hold capacitors during mode transitions to reduce the time period of the transition. | 11-20-2014 |
| 20140361837 | INTEGRATED CIRCUIT WIRELESS COMMUNICATION UNIT AND METHOD FOR PROVIDING A POWER SUPPLY - An integrated circuit comprises a radio frequency (RF) power amplifier (PA) output stage; at least one amplifier stage prior to the RF PA output stage; a linear amplifier comprising a voltage feedback wherein the linear amplifier is operably coupled to a low frequency supply module such that the linear amplifier and low frequency supply module provide a combined first power supply to the RF PA output stage; and a switched mode power supply module arranged to provide a second power supply to the linear amplifier and to the at least one amplifier stage prior to the RF PA output stage. | 12-11-2014 |
| 20150015340 | VARIABLE SWITCHED DC-TO-DC VOLTAGE CONVERTER - A voltage converter can be switched among two or more modes to produce an output voltage tracking a reference voltage that can be of an intermediate level between discrete levels corresponding to the modes. One or more voltages generated from a power supply voltage, such as a battery voltage, can be compared with the reference voltage to determine whether to adjust the mode. The reference voltage can be independent of the power supply voltage. | 01-15-2015 |
| 20150022271 | Dynamic Amplifier Supply - A method of providing a power supply of an amplifier of a wireless transmission system comprising, determining the power at an antenna when transmitting a signal to be transmitted by the amplifier, determining the modulation scheme for transmitting the signal, determining the frequency allocation of the signal to be transmitted, determining a transmit channel characteristic, and adjusting a parameter of the power supply of the amplifier based on the determining steps to maintain amplifier linearity. | 01-22-2015 |
| 20150035606 | TIME AND AMPLITUDE ALIGNMENT IN ENVELOPE TRACKING AMPLIFICATION STAGE - The invention relates to a method of calibrating an envelope path and an input path of an amplification stage including an envelope tracking power supply, the method comprising: generating input signals having a known relationship for each of the input and envelope paths; and varying an amplitude and a delay of the signal in one of the envelope and input paths in order to reduce the variation in the power detected in a signal at the output of the amplification stage. | 02-05-2015 |
| 20150035607 | POWER AMPLIFIER MODULE - Improvement in linearity is achieved at low costs in a power amplifier module employing an envelope tracking system. The power amplifier module includes a first power amplifier circuit that amplifies a radio frequency signal and that outputs a first amplified signal, a second power amplifier circuit that amplifies the first amplified signal on the basis of a source voltage varying depending on amplitude of the radio frequency signal and that outputs a second amplified signal, and a matching circuit that includes first and second capacitors connected in series between the first and second power amplifier circuit and an inductor connected between a node between the first and second capacitors and a ground and that decreases a gain of the first power amplifier circuit as the source voltage of the second power amplifier circuit increases. | 02-05-2015 |
| 20150035608 | DISTORTION COMPENSATING APPARATUS AND DISTORTION COMPENSATION METHOD - A distortion compensating apparatus includes: a memory; and a processor coupled to the memory and configured to: calculate a transient response of a power source circuit, in accordance with an estimated value of a current to be consumed by an amplifier based on a signal to be amplified by the amplifier, and in accordance with an objective supply voltage, based on the signal, of a voltage to be supplied to the amplifier from the power source circuit, and correct the signal to be input to the amplifier based on a difference caused by the transient response from the objective supply voltage. | 02-05-2015 |
| 20150042406 | Peak-to-Average Ratio Detector - An amplifier circuit with a peak-to-average ratio detector is described. Detection of the peak-to-average ratio value can be used to tune one or more parameters that affect linearity of one or more amplifiers in the amplifier circuit to improve amplifier performance. | 02-12-2015 |
| 20150048891 | EXPANDED RANGE DC-DC CONVERTER - A DC-DC converter, which provides a converter output voltage using a DC source voltage, is disclosed. The DC-DC converter includes converter control circuitry and a boosting charge pump. The converter control circuitry selects one of a first boost operating mode, a second boost operating mode, and a boost disabled mode based on the DC source voltage. During the boost disabled mode, the boosting charge pump presents a high impedance at a charge pump output of the boosting charge pump. Otherwise, the boosting charge pump provides a charge pump output voltage. During the first boost operating mode, a nominal value of the charge pump output voltage is equal to about one and one-half times the DC source voltage. During the second boost operating mode, a nominal value of the charge pump output voltage is equal to about two times the DC source voltage. | 02-19-2015 |
| 20150054588 | SUPPLY MODULATOR - There is disclosed an envelope tracking supply modulator comprising a switch mode path and a linear amplifier path, wherein the linear amplifier path includes a plurality of amplifiers, each amplifier having an output stage of a different size, wherein at least one of the plurality of amplifiers is enabled in dependence on an output power. | 02-26-2015 |
| 20150061778 | POWER SUPPLY DEVICE FOR HIGH FREQUENCY POWER AMPLIFYING CIRCUIT AND HIGH FREQUENCY POWER AMPLIFYING APPARATUS - A high frequency power amplifying apparatus includes a power supply device for a high frequency power amplifying circuit, an RF signal processing circuit, and a high frequency power amplifying circuit. Bidirectional converters supplying and/or regenerating an electric charge are provided between an input section of an input voltage and an output section of an output voltage. A converter controlling circuit detects an envelope of an RF input signal, and sets and switches resonant frequencies and amplitudes of the bidirectional converters such that the output voltage follows an amplitude change of an envelope input signal. A delay time detecting circuit detects a delay time of the power supply device for a high frequency power amplifying circuit and makes an adjustment through a delay adjusting circuit. | 03-05-2015 |
| 20150070098 | RF AMPLIFICATION DEVICE WITH POWER PROTECTION DURING HIGH SUPPLY VOLTAGE CONDITIONS - Radio frequency (RF) amplification devices are disclosed along with methods of providing power to an RF signal. In one embodiment, an RF amplification device includes an RF amplification circuit and a voltage regulation circuit. The RF amplification circuit includes a plurality of RF amplifier stages coupled in cascade. The voltage regulation circuit is coupled to provide a regulated voltage to a driver RF amplifier stage. The voltage regulation circuit is configured to generate the regulated voltage so that the maximum output power of the RF amplification circuit is provided approximately at a first power level while the supply voltage is above a threshold voltage level. The first power level should be within the physical capabilities of the RF amplification circuit, and thus, the RF amplification circuit is prevented from being damaged once the supply voltage is above the threshold voltage level. | 03-12-2015 |
| 20150084701 | Integrated Power Supply And Modulator For Radio Frequency Power Amplifiers - An integrated power supply and modulator system includes integrated power supply and modulator system includes three subsystems: a switched-capacitor voltage balancer stage; a magnetic regulation stage; and at least one output switching stage. In one embodiment, the integrated power supply and modulator system further includes startup circuitry, feedback/feedforward circuitry and control circuitry. | 03-26-2015 |
| 20150091655 | Optimal Envelope Tracking Reference Waveform Generation - A method and apparatus is provided to improve upon the efficiency of a power amplifier. Suitable hardware/software in the form of circuitry, logic gates, and/or code functions to construct an envelope tracking waveform of an input communications signal and modulate the input supply voltage based on power amplifier circuitry operational parameters such as slew rates. | 04-02-2015 |
| 20150097625 | HYBRID DC-DC CONVERTERS FOR POWER AMPLIFIERS - Methods and apparatus, including computer program products, are provided for hybrid DC-DC converters. In one aspect, there is provided a method. The method may include tracking, by an envelope detector, an envelope of a signal being amplified by an amplifier. The method may further include supplying, by a first direct-current to direct-current converter, power to the amplifier, the power supplied by the first direct-current to direct-current converter including one or more high-frequency components of the envelope tracked by the envelope detector. The method may further include supplying, by a second direct-current to direct-current converter, power to the amplifier, the power supplied by the second direct-current to direct-current converter including one or more low-frequency components of the envelope tracked by the envelope detector. Related systems, apparatuses, and computer program products are also disclosed. | 04-09-2015 |
| 20150137893 | Parallel Correction Amplifier - A power supply stage and a method of controlling the same comprising: a means for generating an intermediate supply signal in dependence on a reference signal representing a desired power supply; and a plurality of adjusting means, each adapted to generate an adjusted supply signal tracking the reference signal, in dependence on the generated intermediate supply signal and the reference signal. | 05-21-2015 |
| 20150145605 | WIRELESS COMMUNICATION DEVICE - Peak information about an envelope of a high frequency signal extracted from an output of a high frequency power amplifier ( | 05-28-2015 |
| 20150145606 | POWER AMPLIFIER - A power amplifier may include a first amplifying unit receiving a first bias signal to amplify a power level of an input signal; an envelope detecting unit detecting an envelope of the input signal; a comparing circuit unit comparing a peak value of the detected envelope with a preset reference voltage; and a second amplifying unit amplifying the power level of the input signal according to a second bias signal set depending on a comparison result of the comparing circuit unit. | 05-28-2015 |
| 20150318826 | Power supply stage - There is described a method of generating a power supply tracking a reference signal, comprising the steps of: filtering the reference signal; generating a first voltage in dependence on the filtered reference signal; generating a second voltage in dependence on the reference signal; and combining the first and second voltages to provide a power supply voltage. | 11-05-2015 |
| 20150326184 | APPARATUS AND METHODS FOR ENVELOPE TRACKERS - Apparatus and methods for envelope tracking are disclosed. In one embodiment, a power amplifier system including a power amplifier and an envelope tracker is provided. The power amplifier is configured to amplify a radio frequency (RF) signal, and the envelope tracker is configured to control a supply voltage of the power amplifier using an envelope of the RF signal. The envelope tracker includes a buck converter for generating a buck voltage from a battery voltage and a digital-to-analog conversion (DAC) module for adjusting the buck voltage based on the envelope of the RF signal to generate the supply voltage for the power amplifier. | 11-12-2015 |
| 20150349510 | REVERSE BLOCKING APPARATUS FOR ELECTRONIC DEVICE AND SWITCH APPARATUS INCLUDING THE SAME - Reverse blocking apparatus for electronic devices and switch apparatus including the same. In some embodiments, a blocking system for an electronic device can include a determining unit configured to generate an indication signal indicative of a condition associated with an undesirable current in the electronic device. Such an undesirable current can be a reverse current which can damage electronic devices such as transistors. The blocking system can further include a blocking unit in communication with the determining unit. The blocking unit can be configured to be coupled to a terminal of the electronic device. The blocking unit can be further configured to inhibit or reduce passage of the undesirable current in the electronic device based on the indication signal. Examples of applications of such a blocking system and related methods are disclosed. | 12-03-2015 |
| 20150372646 | Linearization Circuits And Methods For Multilevel Power Amplifier Systems - Circuits and methods for achieving high linearity, high efficiency power amplifiers, including digital predistortion (DPD) and pulse cancellation in switched-state RF power amplifier systems are described. | 12-24-2015 |
| 20160006396 | EFFICIENCY FOR LINEAR AMPLIFIER OF ENVELOPE TRACKING MODULATOR - There is disclosed an envelope tracking power supply arranged to generate a modulated supply voltage in dependence on a reference signal, comprising a first path for tracking low frequency variations in the reference signal and a second path for tracking high frequency variations in the reference signal, the second path including a linear amplifier, wherein the output of the linear amplifier comprises a current source and a current sink connected to the high frequency output, there further being provided a DC offset current at the high frequency output. | 01-07-2016 |
| 20160006397 | RESONANCE SUPPRESSION FOR ENVELOPE TRACKING MODULATOR - An envelope tracking power supply arranged to generate a modulated supply voltage in dependence on a reference signal, comprising a first path for tracking low frequency variations in the reference signal and a second path for tracking high frequency variations in the reference signal, and further comprising a combiner having a low frequency combining element for the first path and a high frequency combining element for the second path, and for generating the modulated supply voltage, wherein there is further provided sensing circuitry for sensing a resonance signal in the low or high frequency combining element, and adjusting circuitry for adjusting a signal in the first path in dependence on the sensed resonance signal. | 01-07-2016 |
| 20160013758 | POWER AMPLIFIER WITH TERMINATION CIRCUIT AND RESONANT CIRCUIT | 01-14-2016 |
| 20160043644 | APPARATUS AND METHODS FOR BYPASSING AN INDUCTOR OF A VOLTAGE CONVERTER - Apparatus and methods for bypassing an inductor of a voltage converter are provided. In one embodiment, a voltage converter includes an inductor and a bypass circuit that selectively bypasses the inductor based on a state of a bypass control signal. The inductor includes including a first end electrically connected to a first node and a second end electrically connected to a second node. The bypass circuit includes a first p-type field effect transistor and a second p-type field effect transistor electrically connected in series between the first node and the second node. The first p-type field effect transistor includes a body electrically connected to a first voltage, and the second p-type field effect transistor includes a body electrically connected to a second voltage greater than the first voltage. | 02-11-2016 |
| 20160056770 | RADIO-FREQUENCY HIGH POWER AMPLIFIER WITH BROADBAND ENVELOPE TRACKING BY MEANS OF REVERSED BUCK CONVERTER - A radio-frequency power amplifier with envelope tracking, having a power RF amplifying device for amplifying a RF signal and a switching DC/DC converter for providing the power RF amplifying device with a DC power supply at a voltage level (VSUPP) proportional to an envelope of the RF signal, wherein the switching DC/DC converter has a reversed buck topology. Advantageously the switching device is a N-type GaN Field Effect Transistor having its drain connected to the ground. | 02-25-2016 |
| 20160056779 | WIDEBAND BIAS CIRCUITS AND METHODS - The present disclosure includes circuits and methods for wideband biasing. In one embodiment, an amplifier includes a cascode transistor between an input and an output of the amplifier. The cascode transistor receives a bias from a bias circuit comprising a resistor between the power supply and a first node, a resistor between the first node and a reference voltage, and a capacitor between the power supply and the first node. The power supply may be a modulated power supply, which is coupled through the bias circuit to a capacitance at the control terminal of the cascode transistor. An inductor is configured between a terminal of the cascode transistor and the power supply. The inductor may isolate the output from the modulated supply signal. | 02-25-2016 |
| 20160056813 | DISPLACEMENT CURRENT COMPENSATION CIRCUIT - A displacement current compensation circuit is provided for diverting a displacement current, which flows between a collector and a base of a transistor when a supply voltage for the transistor transitions to a different value. The displacement current compensation circuit includes an inverting amplifier connected to the voltage source, the voltage source being configured to provide the supply voltage to the collector of the transistor; and a coupling network configured to couple an output of the inverting amplifier to the base of the transistor. The inverting amplifier is configured to divert the displacement current from the base of the transistor through the coupling network into the output of the inverting amplifier, thereby preventing the displacement current from entering the base of the transistor. | 02-25-2016 |
| 20160065138 | RF Amplifier Having A Transition Shaping Filter - A radio frequency (RF) power amplifier system or transmitter includes one or more power amplifiers and a controller that is configured to adjust amplitudes and phases of RF input signals of the one or more power amplifiers and supply voltages applied to the one or more power amplifiers. In embodiments where multiple power amplifiers are used, a combiner may be provided to combine outputs of the power amplifiers. | 03-03-2016 |
| 20160072451 | RF POWER TRANSISTOR CIRCUITS - A radio frequency (RF) power transistor circuit includes a power transistor and a decoupling circuit. The power transistor has a control electrode coupled to an input terminal for receiving an RF input signal, a first current electrode for providing an RF output signal at an output terminal, and a second current electrode coupled to a voltage reference. The decoupling circuit includes a first inductive element, a first resistor, and a first capacitor coupled together in series between the first current electrode of the power transistor and the voltage reference. The decoupling circuit is for dampening a resonance at a frequency lower than an RF frequency. | 03-10-2016 |
| 20160087585 | Wideband Self-Envelope Tracking RF Power Amplifier - A wideband self-envelope tracking power amplifier (PA) can use more than a 40-MHz channel bandwidth and improves the envelope bandwidth limit of a self-envelope tracking PAs by ten times. The PA uses an envelope load network, which is based on a general multi-stage low-pass filter. The envelope load network located between an RF choke inductor and main DC power supply provides a dynamically modulated PA supply voltage without using a dedicated envelope amplifier. An input terminal of the network connects a main PA via an RF choke inductor to an input of low-pass filter. An output terminal is connected to the low-pass filter via an envelope choke inductor and to a direct current (DC) power supply. A DC blocker is connected between the output of the low-pass filter and ground by a termination resistor. | 03-24-2016 |
| 20160087590 | Tunable Envelope Tracking - A novel method to provide power management to a radio frequency amplifier is described. The method makes use of a DC-AC resonant switching power converter, a resonant tunable network and a rectifier to track the envelope signal of a radio amplifier system. This system provides a fast, efficient and clean supply to the radio frequency amplifier. The resonant power converter may be implemented with a class E inverter. The resonant power converter may be operated efficiently by switching at zero voltage switching or zero current switching. By operating the resonant switching power converter at the same frequency of the radio frequency amplifier, the spectrum of the power converter is immune from undesired harmonics while meeting the bandwidth requirement. By adaptively tuning the tunable resonant network, the output voltage of the rectifier is controlled to track the envelope signal. | 03-24-2016 |
| 20160094185 | DELAY ADJUSTMENT - There is disclosed an envelope tracking amplification stage comprising an input path and an envelope path and a delay stage in one of the input path and the envelope path, the delay of the delay stage being determined in dependence on the slope polarity of a signal representing the input and whether the signal in the input path leads or lags the signal in the envelope path. | 03-31-2016 |
| 20160094186 | DIGITAL MULTI-LEVEL ENVELOPE TRACKING FOR WIDE-BANDWIDTH SIGNALS - Digital envelope tracking with multilevel supply voltages is performed for wide-bandwidth signals. A digital control component generates a digital control code that facilitates switching of resistor values of one or more resistors coupled between a power amplifier and a supply voltage of plurality of supply voltages. A driver component supplies an envelope voltage of the plurality of supply voltages for the power amplifier as a function of the digital control code. | 03-31-2016 |
| 20160126900 | TRANSFER FUNCTION REGULATION - The invention relates to a technique for controlling in an envelope tracking amplification stage, comprising: determining a representation of the output signal of the amplifier; determining a representation of the input signal of the amplifier; adjusting the determined representation of the input signal according to a target characteristic of the amplifier; comparing the adjusted input and determined representation of the output; and generating a control signal in dependence on the comparison. | 05-05-2016 |
| 20180026590 | POWER CONVERTING SYSTEM | 01-25-2018 |
