Disclosed herein are circuits, devices and methods that address challenges associated with power amplifier systems. A power amplifier system includes two or more fast error amplifiers coupled to corresponding power amplifiers. The fast error amplifiers are configured to generate envelope tracking signals based on a signal envelope, the envelope tracking signals modifying a DC-DC regulated voltage from a DC-DC converter to more efficiently operate the power amplifiers. By splitting the envelope tracking between two or more fast error amplifiers and amplification between corresponding two or more power amplifiers, the power, frequency or bandwidth, linearity, signal-to-noise ratio, efficiency, or the like of the power amplifier system can be improved. Wireless communications configurations with such power amplifier systems can provide uplink carrier aggregation and/or cellular signals based on standards and protocols that require increased bandwidth and/or power.

Fast envelope tracking systems are provided herein. In certain embodiments, an envelope tracking system for a power amplifier includes a switching regulator and a differential error amplifier configured to operate in combination with one another 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 envelope tracking system further includes a differential envelope amplifier configured to amplify a differential envelope signal to generate a single-ended envelope signal that changes in relation to the envelope of the RF signal. Additionally, the differential error amplifier generates an output current operable to adjust a voltage level of the power amplifier supply voltage based on comparing the single-ended envelope signal to a reference signal.

A power supply modulator includes: a linear regulator; a switching regulator; and a mode-based connection circuit. The mode-based connection circuit includes a coupling circuit configured to drop an output signal of the linear regulator by a target coupling voltage in an envelope tracking (ET) modulation mode; and a coupling voltage management circuit configured to monitor a coupling voltage of the coupling circuit in another modulation mode, and selectively apply a voltage to the coupling voltage based on a monitoring result such that the coupling voltage is maintained at the target coupling voltage.

An analog input signal (X.sub.(n)) is processed by a Peak to Average Ratio Reduction (PARR) block to diminish the difference between peak amplitudes and average amplitudes of the analog input signal (X.sub.(n)). After, a distorted signal (h(n)) having low peak to average amplitude ratio, generated at the PARR block output, is processed by a delta sigma modulation (DSM) block converts the distorted signal (h(n)) into a digitally modulated distorted signal (h_dsm.sub.(n)) with high signal to noise ratio (SNR). Afterwards, the digitally modulated distorted signal (h_dsm.sub.(n)) is corrected and amplified by a Class-D RF power amplifier fed by a feeding signal (env.sub.(n)) generated from a digital correction signal (z_dsm.sub.(n)). As a result, a digitally modulated signal (y(n)) with high signal to noise ratio (SNR) of the analog input signal (X.sub.(n)) is generated at the output of the Class-D RF power amplifier.

A data slicer for converting an envelope signal of an amplitude-modulated wave into a binary signal, comprises: an average level generation circuit configured to generate an average level of the envelope signal by averaging the envelope signal per time; a fixed voltage value generation circuit configured to generate a fixed voltage value; a reference level generation circuit configured to generate a reference level in accordance with the fixed voltage value and the average level of the envelope signal; and a comparison circuit configured to compare a signal level of the envelope signal with the reference level to output a result of the comparison as the binary signal.

A digitally-controlled power amplifier (DPA) includes a radio frequency digital-to-analog converter (RF-DAC) constructed from nonlinearly weighted PA segments, a multiphase RF drive signal generator that drives the PA segments, and overdrive voltage control circuitry. The nonlinear weighting of the PA segments intrinsically compensates for amplitude-code-word dependent amplitude distortion (ACW-AM distortion) involved in the operation of the RF-DAC and the multiphase RF drive signal generator facilitates ACW-dependent phase distortion (ACW-PM distortion) reduction, thus obviating the need for complicated and efficiency-degrading digital predistortion. The overdrive voltage control circuitry is used to fine tune the RF output of the DPA and compensate for other non-idealities and external influences such as process, voltage, temperature (PVT), frequency and/or load impedance variations.

A power supply configured to supply a modulated voltage to a power amplifier is shown. The power supply has an alternating current (AC) component generator, a direct current (DC) component generator, and a transition accelerator. The AC component generator generates an AC component of the modulated voltage according to an envelope tracking signal. The DC component generator generates a DC component of the modulated voltage according to the operational voltage range of the power amplifier. The transition accelerator is coupled to an output terminal of the DC component generator to speed up the transition of the modulated voltage.

Circuits and methods for reducing the cost and/or power consumption of a user terminal and/or the gateway of a telecommunications system (550) that may include a telecommunications satellite. Embodiments generate a dynamic input bias signal based upon an information signal envelope (which may be pre-distorted) which is applied to the signal input of a power amplifier (PA), thus reducing average power consumption. Other embodiments further include dynamic linearization (518) of the information signal, and/or variation of the supply voltage to the power amplifier (PA) as a function of the envelope of the information signal. Another aspect is a multi-stage chained feedback regulated voltage supply circuit for providing two or more output voltages that may be used as alternative supply voltages to a power amplifier (PA).

A power converter may include an input for receiving an input signal and output for generating an intermediate signal that is a power converted signal from the input signal wherein the intermediate signal is determined based on various parameters of a signal path that utilizes the intermediate signal, wherein the various parameters comprise one or more of the following: a peak output signal of the signal path, energy requested over a period of time by the signal path, available energy from an energy source to the power converter, stored energy at an output of the power converter, and stored energy of a battery for providing electrical energy at the input.

A multi-radio access technology (RAT) envelope tracking (ET) amplifier apparatus is provided. The multi-RAT ET amplifier apparatus may be configured to enable concurrent communication of at least two radio frequency (RF) signals associated with at least two different RATs. Specifically, the multi-RAT ET amplifier apparatus includes an ET integrated circuit (IC) (ETIC) and a distributed ETIC (DETIC) configured to generate respective ET voltages for amplifying the two RF signals. In addition, the DETIC can be configured to utilize certain circuit(s) in the ETIC to help reduce a footprint of the DETIC. By amplifying the two different RF signals based on the respective ET voltages and sharing certain circuit(s) between the ETIC and the DETIC, it may be possible to improve overall efficiency and heat dissipation in the multi-RAT ET amplifier apparatus concurrent to reducing the footprint of the DETIC.