An analog ET circuit is provided that includes an envelope amplifier and a voltage supply unit. The voltage supply unit is configured to supply plural discrete voltages to the envelope amplifier. The envelope amplifier is configured to receive an envelope signal and the plural discrete voltages and output a continuous output voltage.

A tracker module includes a module laminate configured to provide interconnections to circuit components arranged on the module laminate, at least one integrated circuit arranged on the module laminate, and a first output terminal and a plurality of second output terminals that are configured to output signals externally of the tracker module. The at least one integrated circuit includes a first supply modulator and at least one switch in a switched-capacitor circuit. The switched-capacitor circuit is configured to generate a plurality of discrete voltages, the plurality of discrete voltages being supplied to the plurality of second output terminals to output. The first supply modulator is configured to generate a first power supply by selecting at least one of the plurality of discrete voltages, the first power supply is provided to the first output terminal to output.

Apparatus and methods for power amplifier power management are disclosed. In certain embodiments, a mobile device includes a transceiver that generates a radio frequency signal, a front-end system including a first power amplifier module that amplifies the radio frequency signal, and a power management system including an envelope tracking power management unit that provides an envelope tracking supply voltage to the first power amplifier module, and a first average power tracking power management unit that provides an average power tracking supply voltage to the first power amplifier module. The first power amplifier module is configured to selectively switch between the envelope tracking supply voltage and the average power tracking supply voltage.

Power amplifiers with supply capacitor switching are provided herein. In certain configurations, a power amplifier system includes a power amplifier that provides amplification to a radio frequency (RF) signal, a power management circuit that controls a voltage level of a supply voltage of the power amplifier, a supply capacitor, and a silicon-on-insulator (SOI) switch in series with the supply capacitor between the supply voltage and the a reference voltage, such as ground. The power management circuit is operable in multiple supply control modes including, for example, an average power tracking (APT) mode and an envelope tracking (ET) mode. Additionally, the SOI switch is controlled based on the supply control mode of the power management circuit.

This application provides a power amplification apparatus, a beamforming system, a transmitter, and a base station. The apparatus includes a power amplifier that amplifies a first signal, a power supply, and a power supply modulator that controls, based on an envelope signal corresponding to the first signal, an operating voltage provided by the power supply to the power amplifier. The apparatus is further configured to amplify a second signal. The first signal is generated based on the part of a target amplified signal whose amplitude falls within a preset amplitude range. The second signal is generated based on the part of the target amplified signal whose amplitude falls beyond the preset amplitude range.

A transmitter circuit has a signal input for receiving an analog input signal and a local oscillator (LO) input for receiving an LO signal. A mixer circuit has a first input, a second input, and an output. The second input of the mixer circuit is connected to a signal input of the transmitter circuit. A PA circuit has an input connected to the output of the mixer circuit, and an output. A control circuit generates a phase-control signal and a gain-control signal in response to an envelope of the analog input signal. A phase-control circuit generates a phase-adjusted LO signal in response to the LO signal and the phase-control signal and supplies the phase-adjusted LO signal to the first input of the mixer circuit. A gain-control circuit controls a gain of the transmitter circuit in response to the gain-control signal.

An equalizer circuit and related power management circuit are provided. The power management circuit includes a voltage amplifier circuit configured to generate an envelope tracking (ET) voltage based on a differential target voltage and provide the ET voltage to a power amplifier circuit(s) via a signal path for amplifying a radio frequency signal(s). An equalizer circuit is provided in the power management circuit to equalize the differential target voltage prior to generating the ET voltage. Specifically, the equalizer circuit is configured to provide a transfer function including a second-order complex-zero term and a real-zero term for offsetting a transfer function of an inherent trace inductance of the signal path and an inherent impedance of the voltage amplifier circuit. By employing the second-order transfer function with the real-zero term, it is possible to reduce distortion in the ET voltage, especially when the RF signal(s) is modulated in a wide modulation bandwidth.

Apparatus and methods for pre-distorting a radio frequency transmit signal based on local oscillator clock shaping are disclosed. In certain embodiments, one or more clock signals generated by a local oscillator and used for mixing in a transceiver are shaped to account for non-linearity of a power amplifier that amplifies the radio frequency transmit signal. Such pre-distortion can be performed in addition to or alternatively to performing digital pre-distortion on a digital representation of the radio frequency transmit signal.

Reduced power amplifier size through elimination of matching network. In some embodiments, a power amplification system can include a power amplifier (PA) configured to receive and amplify a radio-frequency (RF) signal. The power amplification system can further include a filter coupled to the PA and configured to condition the amplified RF signal. The PA can be further configured to drive approximately a characteristic load impedance of the filter. Such a configuration of the PA can be achieved by operating the PA with a high-voltage supply. Such a power amplification system can allow elimination of a matching network to, for example, reduce loss and device size.

Embodiments disclosed herein relate to a bias circuit that uses Schottky diodes. Typically, a bias circuit will include a number of transistors used to generate a bias voltage or a bias current for a power amplifier. Many wireless devices include power amplifiers to facilitate processing signals for transmission and/or received signals. By substituting the bias circuit design with a design that utilizes Schottky diodes, the required battery voltage of the bias circuit may be reduced enabling the use of lower voltage power supplies.