Abstract: A method for controlling allotment of power input between at least two PAs of a radio unit for data communication in a wireless communications network is provided. The radio unit has access to Direct Current (DC) power and Photovoltaic (PV) power. The amount of power to be transmitted out from each respective PA out of the at least two PAs established, and information related to the amount of PV power available is obtained. The allotment of power input of DC power and PV power between the at least two Pas is then controlled based on the established amount of power to be transmitted out from each respective PA out of the at least two PAs, and the obtained information related to the amount of PV power available.

Abstract: Maximum voltage detection in a power management circuit is provided. In embodiments disclosed herein, the power management circuit includes a voltage processing circuit configured to receive a first time-variant target voltage having a first group delay relative to a time-variant target voltage and a second time-variant target voltage having a second group delay relative to the time-variant target voltage. The voltage processing circuit includes a maximum signal detector circuit configured to generate a windowed time-variant target voltage that is higher than or equal to a highest one of the first time-variant target voltage and the second time-variant target voltage in a group delay tolerance window(s) defined by the first group delay and the second group delay. In this regard, the windowed time-variant target voltage can tolerate a certain amount of group delay within the group delay tolerance window(s).

Abstract: A circuit to modulate the power supply to track input or output voltages provided to or output by a plurality of amplifiers to reduce power dissipation is provided. The circuit may include a peak detection circuit configured to receive a plurality of voltages respectively corresponding to the plurality of amplifiers, and to detect and output information regarding a maximum instantaneous voltage from the received plurality of voltages, and a summing circuit configured to output a sum of the information regarding the maximum instantaneous voltage and an amplifier headroom voltage. A reference voltage may be provided for the supply voltage responsive to the output sum. The circuit may also include a scaling circuit configured to scale the output sum, and the reference voltage may be a scaled reference voltage output by the scaling circuit.

Abstract: Methods and systems for optimizing amplifier operations are described. The described methods and systems particularly describe a feed-forward control circuit that may also be used as a feed-back control circuit in certain applications. The feed-forward control circuit provides a control signal that may be used to configure an amplifier in a variety of ways.

Abstract: A delay-compensating power management integrated circuit (PMIC) is provided. The PMIC includes a target voltage circuit configured to generate a target voltage that is utilized for generating a time-variant voltage to amplify an analog signal. The target voltage is generated based on a time-variant envelope of the analog signal but lags behind the time-variant envelope by a temporal delay(s) due to an inherent processing delay in the target voltage circuit. In this regard, a voltage processing circuit is provided in the target voltage circuit to generate a modified target voltage that is time-adjusted relative to the target voltage to substantially offset the temporal delay(s). By generating the time-variant voltage based on the modified target voltage, the time-variant voltage can be better aligned with the time-variant envelope of the analog signal, thus helping to reduce amplitude distortion when amplifying the analog signal.

Abstract: Apparatus and methods for saturation detection of power amplifiers are provided. In certain embodiments, a power amplifier system including a power amplifier and a saturation detector is provided. The power amplifier includes a gain transistor that amplifies an RF input signal to generate an RF output signal, and the saturation detector includes a detection transistor that is thermally coupled to the gain transistor. Additionally, the saturation detector monitors an input voltage to the gain transistor to generate a saturation detection signal indicating a saturation of the gain transistor.

Abstract: An amplifier includes an amplifier circuit and a gain adjusting circuit. The amplifier circuit has a design gain and a real gain and is configured to output an output signal according to an input signal and the real gain. The gain adjusting circuit is coupled to the amplifier circuit and is configured to receive the input signal to compare a voltage of the input signal with a first reference voltage, wherein when the voltage of the input signal exceeds the first reference voltage, the gain adjusting circuit increases the real gain of the amplifier circuit, so that the real gain approach the design gain.

Abstract: A continuous time linear equalizer (CTLE) includes a first circuit path having a step response that increases from an first initial value to a steady state value higher than the first initial value. The CTLE also includes a second circuit path in parallel with the first circuit path, the second circuit path having a step response that increases from a second initial value to a peak and subsequently falls to second steady state value that is approximately equal to the second initial value. The CTLE is configured to combine an output of the first circuit path and an output of the second circuit path.

Abstract: A power amplifier circuit includes a first amplifier that amplifies a first RF signal and outputs a second RF signal, a second amplifier that amplifies the second RF signal and outputs a third RF signal, a bias circuit that supplies a bias current or voltage to the first or second amplifier, and a bias adjustment circuit that adjusts the bias current or voltage on the basis of the first RF signal, the second RF signal, or the third RF signal. The bias adjustment circuit includes a first diode having an anode to which a control signal indicating a signal based on the first, second, or third RF signal is inputted, and a cathode connected to a ground. The bias circuit includes a bias transistor that outputs the bias current or voltage on the basis of a voltage at the anode of the first diode.

Abstract: Disclosed is a voltage protection circuit for preventing power amplifier burnout in an electronic device. The electronic device includes a power amplifier (PA) configured to amplify a transmission signal, a switch configured to set a path of a signal outputted from the PA, a bias control circuit configured to control the supply of a bias current driving the PA, and a voltage protection circuit configured to provide a main control signal for turning off the PA earlier than turning off the switch based on a battery voltage providing a driving power of the electronic device, and forward the main control signal to the bias control circuit, wherein, in response to receiving the main control signal instructing to turn off the PA from the voltage protection circuit, the bias control unit stops the supply of the bias current driving the PA.

Abstract: A digital envelop tracker for a power amplifier. The digital envelop tracker includes a supply filter for filtering a supply voltage to a power amplifier, a level selection circuitry configured to determine a level of supply voltage based on an instantaneous power of an input data stream, schedule a series of switching events based on the determined level of supply voltage, and generate a level select signal based on the scheduled series of switching events, and a switch for connecting one of supply voltages to the supply filter based on the level select signal. The level selection circuitry schedules a primary switching event of the switch based on the determined level of supply voltage and secondary switching events of the switch delayed with respect to the primary switching event based on the determined level of supply voltage to generate a filter response of the supply filter with smaller peaking.

Abstract: An apparatus includes a radio-frequency (RF) circuit, which includes a power amplifier coupled to receive an RF input signal and to provide an RF output signal in response to a modified bias signal. The RF circuit further includes a bias path circuit coupled to modify a bias signal as a function of a characteristic of an input signal to generate the modified bias signal. The bias path circuit provides the modified bias signal to the power amplifier.

Abstract: A power amplifier module including an input configured to receive an input radio frequency signal, the input radio-frequency signal including a series of data symbols, an output configured to provide an output radio-frequency signal, a power amplifier having a signal input to receive the input radio-frequency signal and a power supply input to receive a supply voltage, the power amplifier configured to amplify the input radio-frequency signal to provide the output radio-frequency signal, and a controller to receive an indication of a peak output power level of an upcoming data symbol in the series of data symbols, to adjust at least the supply voltage provided to the power amplifier based on the peak output power level of the upcoming data symbol, and to configure the power amplifier module to maintain a substantially constant gain over the series of data symbols.

Abstract: An envelope tracking (ET) power management apparatus incorporating multiple power amplifiers is provided. The ET power management apparatus includes a single ET integrated circuit (ETIC) configured to provide multiple ET voltages to the multiple power amplifiers for amplifying a radio frequency (RF) signal concurrently. The ETIC includes multiple first ET voltage circuits configured to generate multiple first ET voltages and a second ET voltage circuit configured to generate a second ET voltage. The ETIC is configured to provide each of the first ET voltages to an output stage amplifier(s) in a respective one of the power amplifiers and provide the second ET voltage to a driver stage amplifier in all of the power amplifiers. By supporting the multiple power amplifiers using a single ETIC, it is possible to reduce footprint, power consumption, and heat dissipation in an electronic device employing the ET power management apparatus.

Abstract: A supply modulator includes a linear regulator that generates an output voltage in an envelope tracking mode. A switching regulator operates with the linear regulator to generate the output voltage in the envelope tracking mode and to selectively generate the output voltage in an average power tracking mode. A single inductor multiple output converter operates selectively with the switching regulator to generate the output voltage in the average power tracking mode, operates to provide a power supply voltage to the linear regulator in the envelope tracking mode, and includes a first capacitor connected with a power supply terminal of the linear regulator and a second capacitor selectively connected with an output terminal of the linear regulator through a first switch. A main controller decides a tracking mode to be executed by the supply modulator.

Abstract: The present disclosure relates to devices and methods for detecting and preventing occurrence of a saturation state in a power amplifier. A power amplifier module can include a power amplifier including a cascode transistor pair. The cascode transistor pair can include a first transistor and a second transistor. The power amplifier module can include a current comparator configured to compare a first base current of the first transistor and a second base current of the second transistor to obtain a comparison value. The power amplifier module can include a saturation controller configured to supply a reference signal to an impedance matching network based on the comparison value. The impedance matching network can be configured to modify a load impedance of a load line in electrical communication with the power amplifier based at least in part on the reference signal.

Abstract: A high-frequency signal processing apparatus and a wireless communication apparatus can achieve a decrease in power consumption. For example, when an indicated power level to a high-frequency power amplifier is equal to or greater than a second reference value, envelope tracking is performed by causing a source voltage control circuit to control a high-speed DCDC converter using a detection result of an envelope detecting circuit and causing a bias control circuit to indicate a fixed bias value. The source voltage control circuit and the bias control circuit indicate a source voltage and a bias value decreasing in proportion to a decrease in the indicated power level when the indicated power level is in a range of the second reference value to the first reference value, and indicate a fixed source voltage and a fixed bias value when the indicated power level is less than the first reference value.

Abstract: A system may include a first input for receiving a first signal for driving an amplifier that drives a load, a second input for receiving a second signal driven by the amplifier, and an instability detector for detecting instability of a feedback loop for controlling the first signal based on comparison of the first signal and the second signal.

Abstract: A dual-band MMIC power amplifier and method of operation to amplify frequencies in different RF bands while only requiring input drive signals at frequencies f1 and f2 in a narrow RF input band. This allows for the use of a conventional narrowband RF IC to drive the MMIC and does not require additional circuitry (e.g., a LO) on the MMIC power amplifier. The matching network of the last amplification stage is modified to pass f1 (or a harmonic thereof), reflect f2, pass a Pth harmonic of f2 where P is 2 or 3 and to reflect any unused 1st, 2nd or 3rd order harmonics of f1 or f2 back into the MMIC. In response to an input signal at f1, the MMIC power amplifier amplifies and outputs a signal at f1 (or a harmonic thereof). In response to an input signal at f2 at sufficient RF power, the last amplification stage operates in compression such that the MMIC power amplifier generates the harmonics, selects the Pth harmonic and outputs an amplified RF signal at P*f2.

Abstract: Systems, methods, and circuitries are provided for generating a power amplifier supply voltage based on a target envelope signal for a radio frequency (RF) transmit signal. An envelope tracking system includes a first selector circuitry and predistortion circuitry. The first selector circuitry is disposed in a selector module and is configured to input a plurality of voltages conducted on a first plurality of power lanes, wherein the first plurality of power lanes is part of a power distribution network; select a voltage from the plurality of voltages based on the target envelope signal; and provide the selected voltage to a supply lane connected to an input of the power amplifier that amplifies the RF transmit signal. The predistortion circuitry is configured to modify the RF transmit signal based on a selected power lane of the first plurality of power lanes that conducts the selected voltage.

Abstract: Methods and systems for optimizing amplifier operations are described. The described methods and systems particularly describe a feed-forward control circuit that may also be used as a feed-back control circuit in certain applications. The feed-forward control circuit provides a control signal that may be used to configure an amplifier in a variety of ways.

Abstract: A radio-frequency circuit includes a power amplifying circuit configured to amplify a first radio-frequency signal having a first channel bandwidth and a second radio-frequency signal having a second channel bandwidth greater than the first channel bandwidth. The power amplifying circuit is configured to amplify the first radio-frequency signal in an amplifying mode according to an envelope tracking method, and to amplify the second radio-frequency signal in an amplifying mode according to an average power tracking method.

Abstract: Apparatus and methods for envelope controlled radio frequency (RF) switches are provided. In certain embodiments, a power amplifier provides an RF signal to an antenna by way of an RF switch. Additionally, the envelope signal is used not only to control a power amplifier supply voltage of the power amplifier, but also to control a regulated voltage used to turn on the RF switch. For example, a level shifter can use a regulated voltage from charge pump circuitry to turn on the RF switch, and the envelope signal can be provided to the charge pump circuitry and used to control the voltage level of the regulated voltage over time.

Abstract: A multi-bandwidth envelope tracking (ET) integrated circuit (IC) (ETIC) is provided. The multi-bandwidth ETIC may be coupled to an amplifier circuit(s) for amplifying a radio frequency (RF) signal modulated in a wide range of modulation bandwidth. In examples discussed herein, the multi-bandwidth ETIC includes an ET voltage circuit configured to generate a modulated voltage based on a supply voltage. The supply voltage may be dynamically adjusted to cause the modulated voltage to transition quickly from one voltage level to another voltage level, particularly when the RF signal is modulated in a higher modulation bandwidth, without compromising efficiency of the ET voltage circuit. As such, the multi-bandwidth ETIC may generate different modulated voltages based on the modulation bandwidth of the RF signal, thus making it possible to employ the multi-bandwidth ETIC in a wide range of wireless communication devices, such as a fifth-generation (5G) wireless communication device.

Abstract: An envelope tracking supply modulator for a power amplifier is disclosed. The envelope tracking supply modulator comprises a multilevel push-pull converter. The multilevel push-pull converter comprises a control logic configured to generate a first and second control signals based on an envelope reference signal; a source multilevel converter configured to receive the first control signal and generate a source multilevel power supply signal; a sink multilevel converter configured to receive the second control signal and generate a sink multilevel power supply signal. The envelope tracking supply modulator further comprises a power recycling supply coupled to the sink multilevel converter; a low-pass filter coupled to outputs of the source and sink multilevel converters to filter the power supply signals generated from the source and sink multilevel converters.

Abstract: According to one or more embodiments of the disclosure, an electronic device may include a power amplifier, a voltage generator, an antenna, and a communication processor. The CP determines whether an output waveform of the transmission signal which is output through the antenna is a first waveform or a second waveform. If the output waveform is the first waveform, the voltage generator generates a first output voltage for amplifying the first waveform by applying a first direct current (DC) power source of one or more first voltages. If the output waveform is the second waveform, the voltage generator generates a second output voltage for amplifying the second waveform by applying a second DC power source of a second voltage shifted by a designated level with respect to the first voltage, based on a peak power of the first waveform and a peak power of the second waveform.

Abstract: This switching power source 100 has: a switching output circuit 110 which drives an inductor current IL by turning on and off an upper switch 111 and a lower switch 112 and generates an output voltage VOUT from an input voltage PVDD; a lower current detection unit 210 which detects the inductor current IL flowing through the lower switch 112 during an ON-period of the lower switch 112 and acquires lower current feedback information Iinfo; an error amplifier 140 which outputs voltage feedback information Vinfo including information on an error between the output voltage VOUT (feedback voltage FB) and a reference voltage REF; an information synthesis unit 220 that generates synthesis feedback information VIinfo by synthesizing Iinfo with Vinfo; and an information holding unit 230 which samples Vinfo during the ON-period of the lower switch 112.

Abstract: The signal supply device includes a frequency adjuster, a modulator, an amplifier, a current measurer, a frequency setter, and a controller. While the controller executes a test signal supply process for changing a frequency of a carrier wave within a frequency range predetermined as a range of a resonance frequency of an antenna, modulating the carrier wave with a test signal as an input signal, amplifying the carrier wave that is modulated and supplying the carrier wave that is amplified as an output target signal to the antenna, the controller measures an antenna current corresponding to the frequency each time the frequency of the carrier wave is changed. The frequency setter sets, as a usage frequency used as the frequency of the carrier wave, the frequency corresponding to the antenna current on a larger side among the antenna currents measured during execution of the test signal supply process.

Abstract: According to one aspect, embodiments of the invention provide an amplifier system comprising a first phase shifter configured to generate, based on an input signal, a first signal and a second signal, the second signal being out of phase with the first signal, a first amplifier configured to apply a first gain to the first signal to produce a gain adjusted first signal, a second amplifier configured to apply a second gain to the second signal to produce a gain adjusted second signal, a second phase shifter configured to combine the gain adjusted first and second signals to produce an output signal, and a controller configured to identify a high voltage swing across the first amplifier and, in response to identifying the high voltage swing, adjust the first gain to reduce output power of the first amplifier and adjust the second gain to increase output power of the second amplifier.

Abstract: A method for modelling a power amplifier, including memory effect modelling, for general input waveforms and power levels involves generating an extraction waveform having a plurality of tones each having a different frequency, a difference between the frequencies of two adjacent tones of the plurality of tones not being an integer multiple of a difference in frequency between any two other adjacent tones of the plurality of tones. The method further involves providing the extraction waveform to the power amplifier, receiving output from the power amplifier generated in response to the extraction waveform, and generating a model of the power amplifier based on the output.

Abstract: An envelope tracking (ET) amplifier apparatus is provided. The ET amplifier apparatus includes a distributed ET integrated circuit (DETIC) configured to generate a distributed ET voltage. The DETIC may be coupled to a higher-bandwidth (HB) amplifier circuit and a lower-bandwidth (LB) amplifier circuit configured to amplify an HB radio frequency (RF) signal and an LB RF signal, respectively. In examples discussed herein, the DETIC may be configured to selectively provide the ET voltage to one of the HB amplifier circuit and the LB amplifier circuit, depending on which of the HB amplifier circuit and the LB amplifier circuit is activated. By providing the DETIC in proximity to the HB amplifier circuit and the LB amplifier circuit, it may be possible to reduce potential distortion to the HB RF signal and the LB RF signal, without significantly increasing footprint of the ET amplifier apparatus.

Abstract: An oscillatory electric signal having an oscillation frequency is processed by time-sampling to generate a sampled oscillatory electric signal. A nonlinear circuit driven by the sampled oscillatory electric signal outputs a hysteretic response signal as a function of the sampled oscillatory electric signal. The hysteretic response signal has a frequency in a first frequency range as a result of an increase in the oscillation frequency of the oscillatory electric signal, and a frequency in a second frequency range as a result of a decrease in the oscillation frequency of the oscillatory electric signal. A detection circuit processes the hysteretic response signal to compute an envelope signal of the hysteretic response signal, perform a comparison of the envelope signal with a threshold, and produce a signal indicative of an increase or a decrease in the oscillation frequency of the oscillatory electric signal as a result of the outcome of the comparison.

Abstract: A power amplifier module that includes a power amplifier having a plurality of amplifier gain stages, a memory device including a plurality of memory locations, and a controller to receive a control signal having at least one of a first state and a second state. The plurality of memory locations includes at least one first memory location to store a first set of configuration parameters for operation in a first mode, and at least one second memory location to store a second set of configuration parameters for operation in a second mode. The controller configures the power amplifier module in the first mode based on the first set of configuration parameters responsive to receiving the control signal having the first state and configures the power amplifier module in the second mode based on the second set of configuration parameters responsive to receiving the control signal having the second state.

Abstract: Techniques for controlling the output of a power amplifier are disclosed. In one embodiment, the techniques may be realized as a system that includes a power amplifier and a controller coupled to the power amplifier to form a feedback loop. The power amplifier is enabled or disabled in response to a blanking signal. The controller includes an accumulator that stores an accumulated error of the feedback loop. The controller suspends operation of the accumulator when (1) a level of the input signal is below a first threshold for an amount of time that exceeds a second threshold, (2) the blanking signal indicates that the power amplifier is disabled, or (3) both. The controller resumes operation of the accumulator when (1) the level of the input signal is above the first threshold and (2) the blanking signal indicates that the power amplifier is enabled.

Abstract: A switch element is arranged between an input terminal and an output terminal. A signal from the input terminal is distributed by a capacitative element and supplied to the cathode side of a diode. An inductor is connected to the cathode side of the diode, and a smoothing circuit including a capacitative element and a resistor is connected to the anode side. The switch element has a control terminal connected to the anode of the diode, and turns off a path between the input terminal and the output terminal when a voltage is applied to the control terminal.

Abstract: A variable gain amplifier device includes a variable gain amplifier circuitry and a control voltage generating circuitry. The variable gain amplifier circuitry is configured to amplify input signals to generate output signals, wherein the variable gain amplifier circuitry includes a gain setting circuit that is configured to set a gain of the variable gain amplifier circuitry according to a control voltage. The control voltage generation circuitry is configured to simulate at least one circuit portion of the variable gain amplifier circuitry, in order to generate the control voltage according to the input signals and a setting voltage.

Abstract: A solid state power amplifier uses a Doherty power amplifier that can be implemented as a monolithic microwave integrated circuit. By adjusting the DC bias of the amplifying stages in each branch of the Doherty amplifier, the output power, linearity, and DC power can be adjusted to provide a specified output, where the specification for the output can include the maintaining of desired DC power and linearity. The Doherty power amplifier can be used in a satellite payload or other application utilizing solid state power amplifiers, while providing the proper amount of RF output power and DC power. A single amplifier can have its bias levels adjusted for different output levels, helping to minimize the number of designs that are required for a given satellite payload, reducing the variety of parts in a satellite payload.

Abstract: A power converter includes a watchdog circuit having an input adapted to be coupled to a pause signal of a switching power supply. The watchdog circuit is configured to provide a start signal at an output thereof based on the pause signal indicating that the power converter has stopped switching for a threshold duration that is less than an audible range. A pulse generator circuit has an input coupled to the output of the watchdog circuit and is configured to generate at least one pulse based on the start signal. A switch circuit has an input terminal adapted to be coupled to an input voltage and at least one other terminal adapted to be coupled to an inductor. The switch circuit is configured to provide negative current from an output of the power converter through the at least one other terminal based on the at least one pulse.

Abstract: A power amplifier system having a power amplifier with a signal input and a signal output and bias circuitry is disclosed. The bias circuitry includes a bandgap reference circuit coupled between a reference node and a fixed voltage node. A bias generator has a bias input coupled to the reference node and a bias output coupled to the signal input. Also included is a first digital-to-analog converter having a first converter output coupled to the reference node, a first voltage input, and a first digital input, wherein the first digital-to-analog converter is configured to adjust a reference voltage at the reference node in response to a first digital setting received at the first digital input. The first digital setting correlates with an indication of temperature of the power amplifier.

Abstract: An electronic device including: a modem configured to process a baseband signal; an intermediate frequency (IF) transceiver configured to convert the baseband signal provided from the modem into an IF band signal; and a radio frequency (RF) transceiver configured to convert the IF band signal provided from the IF transceiver into an RF band signal, wherein the RF transceiver includes a power amplifier configured to amplify the RF band signal, and a temperature sensor unit to detect a temperature of the power amplifier, and wherein the modem includes a controller configured to control an input power inputted to the RF transceiver based on the temperature of the power amplifier detected by the temperature sensor unit.

Abstract: A group delay optimization circuit is provided. The group delay optimization circuit receives a first signal (e.g., a voltage signal) and a second signal (e.g., a current signal). Notably, the first signal and the second signal may experience different group delays that can cause the first signal and the second signal to misalign at an amplifier circuit configured to amplify a radio frequency (RF) signal. The group delay optimization circuit is configured to determine a statistical indicator indicative of a group delay offset between the first signal and the second signal. Accordingly, the group delay optimization circuit may minimize the group delay offset by reducing the statistical indicator to below a defined threshold in one or more group delay optimization cycles. As a result, it may be possible to pre-compensate for the group delay offset in the RF signal, thus helping to improve efficiency and linearity of the amplifier circuit.

Abstract: A multimode envelope tracking (ET) circuit and related apparatus is provided. The multimode ET circuit is configured to provide an ET voltage(s) to an amplifier circuit(s) for amplifying a radio frequency (RF) signal(s) that may correspond to a wider range of modulation bandwidth. In this regard, the multimode ET circuit is configured to switch dynamically and opportunistically between different operation modes based on the modulation bandwidth of the RF signal(s). In examples discussed herein, the multimode ET circuit is configured to support a single amplifier circuit in a high-modulation-bandwidth mode and an additional amplifier circuit(s) in a mid-modulation-bandwidth mode and a low-modulation-bandwidth mode.

Abstract: A dual-input envelope tracking (ET) integrated circuit (ETIC) and related apparatus are provided. The dual-input ETIC includes an ET voltage circuit configured to generate an ET voltage based on an ET voltage and a first set of parameters. The ET voltage may be provided to a power amplifier circuit(s) for amplifying a radio frequency (RF) signal(s) in an ET power range. The dual-input ETIC also includes a target voltage processing circuit configured to generate the ET target voltage based on a second set of parameters. The dual-input ETIC further includes a control circuit configured to determine the first set of parameters and the second set parameters based at least on the ET power range of the power amplifier circuit(s). As such, it may be possible to optimize the dual-input ETIC performance in a wide-range of modulation bandwidth, thus helping to improve linearity and efficiency of the power amplifier circuit(s).

Abstract: High bandwidth envelope trackers are provided herein. In certain embodiments, an envelope tracking system for a power amplifier includes a switching regulator that operates in combination with a high bandwidth amplifier to generate a power amplifier supply voltage for the power amplifier based on an envelope of a radio frequency (RF) signal amplified by the power amplifier. The high bandwidth amplifier includes an output that generates an output current for adjusting the power amplifier supply voltage, a first input that receives a reference signal, and a second input that receives an envelope signal indicating the envelope of the RF signal. The second input has lower input impedance than the first input to provide a rapid transient response and high envelope tracking bandwidth.

Abstract: An envelope tracking (ET) circuit and related power amplifier apparatus is provided. An ET power amplifier apparatus includes an ET circuit and a number of amplifier circuits. The ET circuit is configured to provide a number of ET modulated voltages to the amplifier circuits for amplifying concurrently a number of radio frequency (RF) signals. The ET circuit includes a target voltage circuit for generating a number of ET target voltages adapted to respective power levels of the RF signals and/or respective impedances seen by the amplifier circuits, a supply voltage circuit for generating a number of constant voltages, and an ET voltage circuit for generating the ET modulated voltages based on the ET target voltages and a selected one of the constant voltages. By employing a single ET circuit, it may be possible to reduce footprint and improve heat dissipation of the ET power amplifier apparatus.

Abstract: A power amplifier (PA) circuit includes a circuit for generating a supply voltage at an upper voltage rail for a power amplifier (PA). The circuit includes a DC-to-DC converter for generating a voltage from which the supply voltage is generated; a linear amplifier for sourcing or sinking current to or from the upper voltage rail via a capacitor for performing fine adjustment of the supply voltage; a first switching device coupled between an output of the linear amplifier and a lower voltage rail to selectively assist the linear amplifier sink current through the capacitor to deal with actual or anticipated transient response of the supply voltage; and a second switching device coupled between the upper voltage rail and the lower voltage rail to selectively discharge the capacitor in response to actual or anticipated transient response of the supply voltage.

Abstract: A bias circuit includes a bias current circuit varying a resistance value according to a mode voltage determined according to a magnitude of an input radio frequency signal, and generating a bias current that is controlled according to the variation of the resistance value; a bias voltage circuit generating a bias voltage that is adjusted according to a change in a power source voltage and supplying the bias voltage to an amplifying circuit; and a bias transfer circuit supplying the bias current to a base node of the amplifying circuit and blocking an input of the radio frequency signal from the base node.

Abstract: Ringing of a signal after passing through a low pass filter in an LINC type linear amplifier is remedied. A linear amplifying device includes the linear amplifier including the low pass filter for removing high-frequency components; and an origin avoiding circuit which receives an original input signal and is provided upstream of the linear amplifier. If the original input signal is sampled in the vicinity of an origin, the origin avoiding circuit modifies a sampled value so at to replace the sampled value with a fixed value, and supplies the modified input signal to the linear amplifier.

Abstract: A high-frequency module includes a transmission signal amplifier that outputs a transmission signal to an antenna terminal side; a reception signal amplifier that amplifies a reception signal supplied from an antenna terminal; a switch that selectively connects the antenna terminal to either an output of the transmission signal amplifier or an input of the reception signal amplifier; and a directional coupler that is provided on a transmission signal path and detects a signal level of the transmission signal. The transmission signal amplifier is controlled by a first control signal supplied from a first control circuit. The reception signal amplifier is controlled by a second control signal supplied from a second control circuit. The switch is controlled by a switch control signal supplied from the first control circuit. The directional coupler is controlled by a coupler control signal supplied from the first control circuit.

Abstract: A method for processing a digital audio broadcast signal includes: separating an analog audio portion and a digital audio portion of the digital audio broadcast signal; determining the loudness of the analog audio portion and the digital audio portion over a first short time interval; using the loudness of the analog and digital audio portions to calculate a short term average gain; determining a long term average gain; converting one of the long term average gain or the short term average gain to dB; if an output has been blended to digital, adjusting a digital gain parameter by a preselected increment to produce a digital gain parameter; if an output has not been blended to digital, setting the digital gain parameter to the short term average gain; providing the digital gain parameter to an audio processor; and repeating the above steps using a second short time interval.