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.

An amplifier circuit includes a voltage-to-current conversion circuit and a current-to-voltage conversion circuit. The voltage-to-current conversion circuit generates a current signal according to an input voltage signal, and includes an operational transconductance amplifier (OTA) used to output the current signal at an output port of the OTA. The current-to-voltage conversion circuit generates an output voltage signal according to the current signal, and includes a linear amplifier (LA), wherein an input port of the LA is coupled to the output port of the OTA, and the output voltage signal is derived from an output signal at an output port of the LA.

Envelope tracking power supply circuitry includes a look up table (LUT) configured to provide a target supply voltage based on a power envelope measurement. The target supply voltage is dynamically adjusted based on a delay between the power envelope of an RF signal and a provided envelope tracking supply voltage. The envelope tracking supply voltage is generated from the adjusted target supply voltage in order to synchronize the envelope tracking supply voltage with the power envelope of the RF signal.

Envelope tracking power supply circuitry includes a look up table (LUT) configured to provide a target supply voltage based on a power envelope measurement. The target supply voltage is dynamically adjusted based on a delay between the power envelope of an RF signal and a provided envelope tracking supply voltage. The envelope tracking supply voltage is generated from the adjusted target supply voltage in order to synchronize the envelope tracking supply voltage with the power envelope of the RF signal.

Envelope tracking power supply circuitry includes a look up table (LUT) configured to provide a target supply voltage based on a power envelope measurement. The target supply voltage is dynamically adjusted based on a delay between the power envelope of an RF signal and a provided envelope tracking supply voltage. The envelope tracking supply voltage is generated from the adjusted target supply voltage in order to synchronize the envelope tracking supply voltage with the power envelope of the RF signal.

Envelope tracking power supply circuitry includes a look up table (LUT) configured to provide a target supply voltage based on a power envelope measurement. The target supply voltage is dynamically adjusted based on a delay between the power envelope of an RF signal and a provided envelope tracking supply voltage. The envelope tracking supply voltage is generated from the adjusted target supply voltage in order to synchronize the envelope tracking supply voltage with the power envelope of the RF signal.

Apparatus and methods for power amplifier bias modulation for low bandwidth envelope tracking are provided herein. In certain embodiments, an envelope tracking system includes a power amplifier that amplifies an RF signal and a low bandwidth envelope tracker that generates a power amplifier supply voltage for the power amplifier based on an envelope of the RF signal. The envelope tracking system further includes a bias modulation circuit that modulates a bias signal of the power amplifier based on a voltage level of the power amplifier supply voltage.

A power amplifier module can include one or more switches, a coupler module, input signal pins, and a controller having first and second output terminals. The input signal pins can receive a voltage input/output signal, a clock input signal, and a data input signal. The controller can (i) set a mode of the one or more switches using a synchronous communication protocol in which the controller outputs a synchronous clock signal on the first output terminal and a data signal on the second output terminal, when the power amplifier module is in a first operating mode, or (ii) set a mode of the coupler module using an asynchronous communication protocol in which the controller outputs a first asynchronous control signal on the first output terminal and a second asynchronous control signal on the second output terminal, when the power amplifier module is in a second operating mode.

A subharmonic switching digital power amplifier system includes a power amplifier core that includes at least one power amplifier operable in a power back-off region and a power supply providing at least one operating voltage to the power amplifier. Characteristically, the power amplifier is toggled at a subharmonic component of a carrier frequency (Fc) to achieve power back-off wherein the power amplifier is operated in a voltage mode or current mode driver. Multi-subharmonics can be used to further enhance the power back-off efficiency. A switching digital power amplifier system employing phase interleaving is also provided.

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.