633results about "Amplifier details" patented technology

An adaptable, generalized digital predistortion system that can increase the accuracy of the distortion applied to a power amplifier input signal is disclosed. Further, the digital predistortion system can be implemented using a reduced circuit area by reducing a number of coefficients used by the models applied to generate the distortion compensation signal. Further, the system can implement an improved digital predistortion adaptation engine that can improve one or more of the following metrics of a complete radio frequency (RF) analog front-end radio signal chain: error vector magnitude (EVM), adjacent channel leakage ratio (ACLR), spectrum emission mask (SEM), and power consumption of the circuits and systems. An example of circuits and systems is a radio frequency power amplifier (PA).

A class D amplifier circuit receives an analog audio signal with a first reference voltage as its center level, and outputs an output pulse signal having a duty cycle that corresponds to the analog audio signal. A bias circuit generates a second reference voltage having a voltage level obtained as a division of the first reference voltage and the power supply voltage. A periodic voltage generating circuit of the class D amplifier circuit generates a periodic voltage having a triangle waveform or otherwise a sawtooth waveform having an amplitude that corresponds to the second reference voltage.

A power amplifier includes a main switched capacitor power amplifier (SCPA), a peak SCPA, and a shunt inductor. The main SCPA is electrically coupled to a load. The peak SCPA is in parallel with the main SCPA and electrically coupled to the load. The shunt inductor is electrically coupled between the peak SCPA and the load.

An electronic device may include a transmitter coupled to an antenna over a signal path that runs through a front end module. The front end module may include a power amplifier disposed on the signal path. The front end module may include first, second, and / or third signal attenuators disposed on the signal path between an input of the amplifier and the transmitter. The front end module may include a voltage sensor that measures a bias voltage of the amplifier, a temperature that measures a temperature of the amplifier, and / or an impedance sensor that measures an impedance of the antenna. The first signal attenuator may be adjusted based on the measured bias voltage, the second signal attenuator may be adjusted based on the measured temperature, and the third signal attenuator may be adjusted based on the measured impedance to mitigate changes in the amplifier as operating conditions change over time.

A low-noise amplifier (LNA) includes a first transistor, a second transistor, and a load coupled to a drain of the first transistor and a drain of the second transistor. The LNA also includes a first reactive impedance matching network including a first inductor and a second inductor inductively coupled with the first inductor, wherein the first inductor is coupled to a source of the first transistor, and the second inductor is coupled to a gate of the first transistor. The LNA also includes a second reactive impedance matching network including a third inductor and a fourth inductor inductively coupled with the third inductor, wherein the third inductor is coupled to a source of the second transistor, and the fourth inductor is coupled to a gate of the second transistor. The LNA also includes a switching circuit configured to enable or disable each of the reactive impedance matching networks.

Systems and techniques are provided for power amplifier gain error compensation for a Digital Power Amplifier (DPA). In some aspects, a compensation method includes obtaining in-phase (I) and quadrature-phase (Q) components of a baseband sample corresponding to in-phase input amplitude codes and quadrature-phase input amplitude codes. The in-phase input amplitude codes can be distorted based on first gain pre-compensation information corresponding to an in-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the I component. The quadrature-phase input amplitude codes can be distorted based on second gain pre-compensation information corresponding to a quadrature-phase signal branch of the DPA, to generate pre-distorted output amplitude codes of the Q component. The DPA can be driven using the pre-distorted output amplitude codes of the I and Q components to generate a Radio Frequency (RF) output.

An impedance matching network for a radio frequency (RF) transmission system can include first port for coupling to a first transistor differential pair. The network can further include a second port for coupling to a second transistor differential pair. The network can further include a matching network connected to the first port and the second port, the matching network comprised of a pair of coupled lines. Other aspects are described.

One or more systems, devices and / or methods of use provided herein relate to a baseband filter that can be used in a current-mode end-to-end signal path. The current-mode end-to-end signal path can include a digital to analog converter (DAC) operating in current-mode and an upconverting mixer, operating in current-mode and operatively coupled to the DAC. In one or more embodiments, a device used in the signal path can comprise a baseband filter that receives an input current and outputs an output current. The baseband filter can comprise a feedback loop component having an active circuit branch and a passive circuit branch coupled in a loop. A mirroring device can be coupled to the feedback loop component and can provide an output of the device. Selectively activating the mirroring device can vary gain, such as of the mirroring device.

Dynamic adjustment of the power amplifier bias of a power amplifier. Circuitry, disposed within an apparatus, measures the power level presently being handled by the power amplifier. The circuitry adjusts the power amplifier bias for a power amplifier based on the measurement of the power level presently being handled by the power amplifier and a desired fidelity experienced by RF signals processed by the power amplifier. The adjustment in the power amplifier bias for the power amplifier causes an adjustment in a power consumption of the power amplifier, thereby enabling great saving in the DC power required by a power amplifier, and thus, substantially reduces the power consumption of the apparatus in which it operates, such as a Remote PHY node, a Remote MACPHY node, a HFC RF amplifier, a wireless communication device, cellular transmission equipment, or a satellite transponder, for example.

According to embodiments, a method performed by an electronic device includes: identifying a channel bandwidth; identifying one or more active DPD units among a plurality of DPD units of a digital pre-distortion (DPD) circuit based on the channel bandwidth and amount of resource allocated within the channel bandwidth; generating a DPD output signal of the DPD circuit based on the one or more active DPD units; generating an amplifier output signal based on the DPD output signal of the DPD circuit, a digital-to-analog converter (DAC), and a power amplifier (PA). While the DPD output signal is generated, at least one DPD unit different from the one or more active DPD units among the plurality of DPD units of the DPD circuit is deactivated.

An LNA with inductive source degeneration provided by a degeneration network is presented. The degeneration network includes an inductor in parallel with a stability compensation network for provision of unconditional stability with reduced effect on in-band performance of the LNA. The stability compensation network includes an RLC network comprising a resistor, an inductor and a capacitor in series connection. According to one aspect, a resonant frequency provided by the series-connected inductor and capacitor is selected based on a known frequency of instability. Values of the resistor, inductor and capacitor are iteratively derived based on an optimization routine with criteria that includes a magnitude of the μ-factor. The criteria further include an in-band RF performance of the LNA. According to another aspect, initial values of the inductor and capacitor are selected for an initial value of the resonant frequency to be equal to about 10× the in-band frequency.

A signal processing device includes a circuit system, in which the circuit system includes an amplifier, a temperature compensating circuit and a computing circuit. The amplifier is configured to amplify an input signal according to a temperature compensating current, in order to generate an output signal. A direct current offset of the output signal is related to the temperature compensating current. The temperature compensating circuit includes a detecting resistor and a comparator. The detecting resistor is configured to generate a detecting voltage according to the temperature compensating current. The comparator is configured to compare the detecting voltage with a reference voltage to generate a comparison signal. The computing circuit is configured to adjust the temperature compensating current according to the comparison signal so as to make the detecting voltage approximate to the reference voltage.

An analog front end (AFE) circuit including: a continuous time linear equalizer (CTLE) circuit; a transimpedance amplifier (TIA) connected to the CTLE circuit; and a feedback circuit including: a first transistor connected between a first output of the feedback circuit and a first node connected to a first current source; a second transistor connected between a second output of the feedback circuit and a second node connected to a second current source; and a first tunable resistor coupled between the first node and the second node, wherein: a first input of the feedback circuit is connected to a first output of the TIA; a second input of the feedback circuit is connected to a second output of the TIA; the second output of the feedback circuit is connected to a first input of the TIA.

Aspects of this disclosure relate to squelching a symbol at a symbol boundary. A transmit squelch block can squelch a portion of a symbol at a symbol boundary. The transmit squelch block can be included in a symbol based envelope tracking system. Transmit squelching can reduce spurious emissions associated a symbol based envelope tracking voltage toggling on a symbol boundary.

In one embodiment, an apparatus includes a baseband processor to generate a baseband signal and a digital pre-distortion (DPD) circuit to pre-distort the baseband signal with compensation information obtained from a lookup table. The lookup table may have a plurality of entries each to store a pre-distortion value, the lookup table to be addressed based on a target output power level of the baseband signal. The apparatus also may include a converter to convert the pre-distorted baseband signal to an analog signal and radio frequency (RF) circuitry comprising: a mixer to upconvert the analog signal to a pre-distorted RF signal, and a power amplifier to amplify the pre-distorted RF signal.

Apparatus and methods for fast and accurate biasing of LNAs are provided herein. In certain embodiments, an LNA includes an amplification circuit that amplifies a radio frequency (RF) input signal, and a biasing circuit that generates a bias voltage for the amplification circuit based on comparing a sensed bias current through the amplification circuit to a reference current.

Provided is a single differential-based balanced amplifier including one differential amplifier configured to receive a first differential input signal and a second differential input signal having a phase difference of 180 degrees from the first differential input signal, and output a first differential output signal at a first output terminal and a second differential output signal at a second output terminal, a phase delay circuit configured to receive the first differential output signal, and output a third differential output signal obtained by adjusting a phase of the first differential output signal relative to the second differential output signal by 90 degrees, and a hybrid coupler configured to receive the second differential output signal at a first port, receive a third differential output signal at a third port, and output, at a second port, an in-phase signal in which RF power of the second differential output signal and the third differential output signal are combined in phase.

A control device (100) for controlling a number N, with N ≥ 1, of actuators (200) for actuating N optical elements (310) of an optical system (300), comprising a control node (K2) coupling to the actuator (200) for providing a control voltage (V2) for the actuator (200), and an amplifier (110) configured to receive a supply voltage (V1) provided at an input node (K1) and to provide an output voltage (V3) at an output node (K3), wherein the amplifier (110) comprises a plurality M, with M ≥ 2, of current sources (111, 112) comprising at least one controlled current source (112) and a holding capacitor (113) for maintaining the level of the provided output voltage (V3), wherein the controlled current source (112) comprises a transistor (114), whose gate terminal can be controlled by an adjustable first control signal (S1),and has an adjustable resistor (115) coupled to the transistor (114).

A power modulator is provided. The power modulator includes: a multi-output voltage regulator (MOVR) configured to output a plurality of voltages in a discrete level envelope tracking mode (DLETM), the plurality of voltages having mutually different levels corresponding to reference output voltage signals; a switching regulator configured to output a switching regulator voltage, the output voltage depending on a selected voltage among the plurality of voltages and the switching regulator voltage in the DLETM, and the output voltage depending on the switching regulator voltage in the average power tracking mode; a switching regulator controller configured to sense an output current of the MOVR to obtain a sensed value, and to control the switching regulator based on the sensed value in the DLETM; a switch array including a plurality of switches corresponding to the plurality of voltages, respectively, and configured to selectively connect the selected voltage to a power amplifier by performing a switching operation; and a switch controller configured to control the switching operation.

To provide a high-precision overcurrent protection circuit.SOLUTION: An overcurrent protection circuit 34 includes: a first transistor M1 and a second transistor M2 configured to form an amplifier input stage that receives an input of a detection signal Vs according to a monitoring target current IOUT; and a third transistor M3 configured to form an amplifier output stage that generates a current output signal Ic according to a difference between the detection signal Vs and a reference signal Vref and causes the current output signal Ic to be negatively fed back to the amplifier input stage. The monitoring target current IOUT is limited on the basis of the current output signal Ic output from the third transistor M3.SELECTED DRAWING: Figure 3

A Differential Input, Single-ended Output Quadrature Hybrid Coupler (DISO-QHC) is based on baluns, one or two phase shifters, and a Wilkinson combiner. The DISO-QHC is configured to receive two differential, quadrature RF signals from differential PAs and output a combined, single-ended RF signal to drive an antenna element or subarray. Impedance matching transformers configured as baluns perform the differential-to-single-ended conversion and PA output impedance matching, without any requirement on coupling factor. One or two phase shifting circuits align the single-ended, quadrature RF signals in phase. A Wilkinson combiner circuit combines the power of the outputs of the phase shifting circuits. Area and losses are reduced by combining components from the phase shifting circuits with the baluns, and with the Wilkinson combiner circuit (which is implemented with lumped-reactance components rather than transmission lines). The DISO-QHC does not have a specific isolation port, but the isolation resistor within the Wilkinson combiner dissipates the differential and reflected signal from the PAs resulting from the incoming wave reflected from the antenna. The DISO-QHC is compatible with a LMBA functionality. By injecting a current at the center point of the isolation resistor in the Wilkinson combiner, the impedance at PA ports can be modulated.

Apparatus and techniques for adaptively adjusting an input current limit of a boost converter that supplies power to a load, such as an amplifier. An exemplary circuit for supplying power generally includes a boost converter having an output coupled to the load, and logic configured to adaptively adjust the input current limit of the boost converter and apply the input current limit to the boost converter based on an estimated output power of the boost converter. One exemplary method for supplying power generally includes converting an input voltage to an output voltage by a boost converter to power a load for the boost converter, adaptively adjusting the input current limit of the boost converter based on the estimated output power of the boost converter, and applying the input current limit to the boost converter during conversion.

The transistor amplifier package includes a package substrate having a conductive pattern exposed at a surface of the package substrate by a solder mask pattern, and at least one transistor die having a semiconductor structure attached to the surface of the package substrate by a solder material and aligned by the solder mask pattern, whereby respective gate, drain, and / or source terminals of the at least one transistor die are electrically connected to respective conductive patterns of the conductive patterns. Related transistor amplifiers and fabrication methods are also discussed.

Disclosed herein is reducing equivalent series resistance (ESR) of a power management circuit during a single transmission. The power management circuit includes a plurality of power amplifier circuits each configured to amplify a signal for transmission. The power management circuit includes a main multi-stage charge pump (MCP), a first voltage modulation circuit, a light-weight MCP, and a second voltage modulation circuit. When only one of the power amplifiers is active to amplify a signal for a single transmission, the power management circuit will opportunistically couple the main MCP, the first voltage modulation circuit, the light-weight MCP, and the second voltage modulation circuit to the active power amplifier. Thus, the active power amplifier will see a reduced ESR collectively presented by the main MCP, the first voltage modulation circuit, the light-weight MCP, and the second voltage modulation circuit, and can therefore operate with improved efficiency during the single transmission.

Embodiments described herein relate to methods and apparatuses for performing digital predistortion, DPD, to provide a transmit signal, x̆(n) wherein the transmit signal, x̆(n), is for deriving one or more amplifier signals, x̆m(n), for driving one or more power amplifiers, wherein the one or more power amplifiers are associated with a respective one or more antenna elements. A method comprises: receiving a first signal, x(n); inputting the first signal, x(n), into a combination model, wherein the combination model comprises a machine learning, ML, model and a memory polynomial, MP, model; and outputting the transmit signal x̆(n), from the combination model.

In an embodiment, a circuit includes a first input terminal configured to be coupled to a first terminal of a first capacitor, a second input terminal configured to be coupled to a second terminal of the first capacitor, a balun including a primary inductor and a secondary inductor, and a second capacitor. The primary inductor includes a first terminal coupled to the first input terminal, a second terminal coupled to the second input terminal, a first inductive portion coupled between the first terminal of the primary inductor and a first intermediate terminal, a second inductive portion coupled between the second terminal of the primary inductor and a second intermediate terminal, and a third inductive portion coupled between the first and second intermediate terminals. The secondary inductor includes a first terminal coupled to a ground terminal. The second capacitor is coupled between the first and second intermediate terminals.

The invention discloses an automatic gain control circuit, an automatic gain control method and communication equipment. The automatic gain control circuit comprises a first gain module and a receiving control module, the receiving control module comprises an attenuation unit and an acquisition unit, the first gain module is used for receiving an input signal, and the first gain module, the attenuation unit and the acquisition unit are connected in sequence; the first gain module is configured to reduce the gain when the attenuation amount of the attenuation unit reaches a preset attenuation threshold value and the signal intensity of the input signal is greater than the preset intensity of the acquisition unit; and the attenuation unit is configured to attenuate the signal intensity of the input signal step by step when the signal intensity of the input signal after gain is greater than the preset intensity of the acquisition unit. By adopting the scheme, the linearity of the circuit is improved, and the circuit cost is reduced.

Aspects of temperature dependent stabilization and peaking control in amplifiers are described. An example amplifier includes a variable gain amplifier, a power amplifier, a variable compensation element coupled to the variable gain amplifier, and a controller that directs operation of the variable compensation element to adjust one or more operating characteristics of the amplifier. In one aspect, the variable compensation element comprises a variable impedance, and the controller varies the impedance across inputs of the variable gain amplifier based on temperature to stabilize the amplifier. In another aspect, the variable compensation element comprises a negative capacitance, and the controller varies a coupling of the negative capacitance across inputs of the variable gain amplifier based on temperature to linearize gain of the amplifier. The variable compensation element can include both a variable impedance and negative capacitance, and stability, peaking control, and linearity of the amplifier can be controlled.

This application relates to a predistortion circuit for a wireless transmitter and a method for generating a predistorted baseband signal. Specifically, the invention discloses a predistortion circuit for a wireless transmitter, comprising a signal input configured to receive a baseband signal. Furthermore, the predistortion circuit includes a predistorter configured to generate a predistorted baseband signal using the baseband signal and a selection of a first predistorter configuration and a second predistorter configuration.

A power supply switch circuit includes a first switch configured to supply a first power supply voltage to a power supply terminal of a power amplifier, a control voltage generator configured to compare a first voltage of the power supply terminal with a predetermined first reference voltage to generate a first control voltage higher than the first power supply voltage, and a switch controller configured to use the first control voltage to generate a switching driving signal controlling the first switch.