Power amplification system with adaptive bias control. In some embodiments a power amplification system includes a power amplifier including a radio-frequency (RF) input terminal for receiving an RF signal, an RF output terminal for providing an amplified RF signal, a supply voltage terminal for receiving a power amplifier supply voltage to power the power amplifier, and one or more bias terminals for receiving one or more bias signals. The power amplification system also includes a bias controller configured to provide the one or more bias signals to the one or more bias terminals, at least one of the one or more bias signals being based on the power amplifier supply voltage.

An apparatus for and method of a supply modulator (SM) for a power amplifier (PA) is provided. The apparatus includes a buck-boost converter, including a supply input connected to a battery voltage (Vbat), and an output; and a buck converter, including a supply input connected to Vbat, an input connected to the output of the buck-boost converter, and an output.

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.

A two-way Doherty amplifier for amplifying a modulated or non-modulated carrier signal, said carrier signal having a carrier frequency; wherein the Doherty amplifier comprises a first amplifier having a first amplifier output node, a second amplifier having a second amplifier output node, a combining node connected or connectable to a load, a first amplifier output line connecting the first amplifier output node to the combining node, and a second amplifier output line connecting the second amplifier output node to the combining node, and wherein the first amplifier output line has an electrical length of substantially one quarter wavelength of the carrier signal and the second amplifier output line has an electrical length of substantially one half wavelength of the carrier signal.

A power amplifier of an envelope tracking system is configured to generate an output power with a variable supply voltage that is generated in an envelope tracking path. A signal generation/processing path receives an input signal and processes the input signal to the power amplifier in a main signal processing path. A delay component is configured to generate a delay to the envelope tracking path with respect to the signal generation path. A feedback path is configured to generate a feedback signal from the output of the power amplifier and adjust the delay component or the delay of the delay component during an active transmission or an active transmission mode.

Apparatus and methods for envelope shaping in a mobile device are provided. In certain implementations, a mobile device includes an envelope tracker configured to control a voltage level of a power amplifier supply voltage based on a shaped envelope signal, a power amplifier configured to receive the power amplifier supply voltage and to provide amplification to a radio frequency signal, and a transceiver including a modulator configured to generate the radio frequency signal and an envelope shaping circuit configured to generate the shaped envelope signal by shaping an envelope of the radio frequency signal. The envelope shaping circuit includes a shaping table configured to maintain a substantially constant distortion in a transmit band of the mobile device across a range of the envelope of the radio frequency signal.

An apparatus for generating a plurality of power supply signals for a plurality of power amplifiers configured to amplify radio frequency transmit signals includes a first power supply circuit configured to generate a first power supply signal and a different second power supply signal. The first power supply circuit is configured to provide the first power supply signal to a first output path and the second power supply signal to a second output path. Further, the apparatus includes a second power supply circuit configured to generate a third power supply signal. Still further, the apparatus includes a switching circuit configured to couple the second power supply circuit to the first output path in a first operating mode to provide a first combined power supply signal at an output of the first output path based on the first power supply signal and the third power supply signal.

A multi-phase amplifier circuit includes an amplification circuit configured to generate a plurality of phase signals and to provide the plurality of phase signals to a plurality of inductors. An inductive coupling between a first pair of inductors differs from an inductive coupling between a second pair of inductors by a first coupling difference. The amplification circuit is configured to provide two phase signals comprising a first phase difference of less than 180 to the first pair of inductors and two further phase signals comprising the first phase difference to the second pair of inductors. An inductive coupling between a third pair of inductors differs from an inductive coupling between a fourth pair of inductors by a second coupling difference. The amplification circuit is configured to provide two phase signals comprising a second phase difference of 180 to the third pair of inductors and two further phase signals comprising the second phase difference to the fourth pair of inductors.

The embodiments described herein include amplifiers that are typically used in radio frequency (RF) applications. The amplifiers described herein use a buffer that is implemented inside the device package. Specifically, the amplifiers can be implemented with a gate bias modulation buffer inside the device package, where the gate bias modulation buffer is configured to provide a modulated bias signal to a transistor gate of the amplifier.

A PA power supply, which includes a first ET power supply, power supply control circuitry, a first PMOS switching element, and a second PMOS switching element, is disclosed. During a first operating mode, the power supply control circuitry selects an OFF state of the first PMOS switching element, selects an ON state of the second PMOS switching element, and adjusts a voltage of a first switch control signal to maintain the OFF state of the first PMOS switching element using a voltage at a source of the first PMOS switching element and a voltage at a drain of the first PMOS switching element; the PA power supply provides a first PA power supply signal; and the first ET power supply provides a first ET power supply signal, such that the first PA power supply signal is based on the first ET power supply signal.