A power amplifier circuit including a plurality of analog power amplifiers configured to generate a output power for an output signal; at least one processor configured to: select a highest output power signal; determine an input signal power of a modulated signal; determine an output signal power based on the input signal power; compare the output signal power and the highest output power; and disable a subset of the plurality of analog power amplifiers based on the comparison, wherein a remainder of the plurality of analog power amplifiers are configured to generate the output signal power.

An apparatus for detecting difference in operating characteristics of a main circuit by using a replica circuit is presented. In one exemplary case, a sensed difference in operating characteristics of the two circuits is used to drive a tuning control loop to minimize the sensed difference. In another exemplary case, several replica circuits of the main circuit are used, where each is isolated from one or more operating variables that affect the operating characteristic of the main circuit. Each replica circuit can be used for sensing a different operating characteristic, or, two replica circuits can be combined to sense a same operating characteristic.

Apparatus and methods for envelope tracking systems with automatic mode selection are provided herein. In certain configurations, a power amplifier system includes a power amplifier configured to provide amplification to a radio frequency signal and to receive power from a power amplifier supply voltage, and an envelope tracker including a signal bandwidth detection circuit configured to generate a detected bandwidth signal based on processing an envelope signal corresponding to an envelope of the radio frequency signal. The envelope tracker further includes a switch bank configured to receive a plurality of regulated voltages, a filter configured to filter an output of the switch bank to generate the power amplifier supply voltage, and a mode control circuit configured to control a filtering characteristic of the filter based on the detected bandwidth signal.

According to various embodiments, an electronic device may include: a communication processor, a radio frequency (RF) integrated circuit (RFIC) configured to receive a signal output from the communication processor and to modulate the signal into an RF signal, a power management circuit, a first power amplifier configured to amplify an RF signal output from the RFIC based on power supplied from the power management circuit, a second power amplifier configured to amplify the RF signal output from the RFIC based on the power supplied from the power management circuit, at least one capacitor connected in parallel to a power supply terminal of the first power amplifier, and at least one switch connected between the power supply terminal and the at least one capacitor, wherein the communication processor is configured to: identify a power amplification mode based a frequency band of the RF signal, and control the at least one switch by outputting a control signal corresponding to the identified power amplification mode.

Low noise amplifiers (LNAs) are disclosed herein. In certain embodiments, an LNA includes an input balun configured to convert a single-ended radio frequency (RF) receive signal to a differential RF receive signal, an amplifier chain configured to amplify the differential RF receive signal to generate a differential amplified RF receive signal, and an output balun configured to convert the differential amplified RF receive signal into a single-ended amplified RF receive signal. The LNA's amplifier chain is operable in multiple gain modes, and includes a first differential amplification stage, a second differential amplification stage, and a third differential amplification stage.

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.

An amplifier having one or more channels where each channel includes a two half bridges (a master and slave sub-channel). The sub-channels can be connected either in parallel or in a full-bridge configuration via internal switches that route signals to a pair of speaker jacks. One switch in the amplifier has a first position that selectively connects the outputs of the master and slave sub-channel to the same input of the speaker load so that the two sub-channels will drive the speaker load in parallel and a second position where the output of the slave sub-channel is connected to another input of the speaker load so that the master sub-channel and the slave sub-channel will drive the speaker load in a Full-bridge configuration. A second switch has a first position that connects a second input of the speaker load to ground or reference potential of the sub-channels when the speaker load is to be driven in parallel and a second position that is a No-connect position that is used when the speaker load is driven in the Full-bridge configuration and a ground potential is not to be connected to the speaker.

A method and apparatus. The method includes: a terminal device sends a carrier aggregation (CA) capability reporting message to a network device, where the CA capability reporting message includes a frequency separation class of each of at least one radio frequency (RF) channel of the terminal device and a power amplifier (PA) architecture of the terminal device. The PA architecture indicates that the PA architecture that can be used by the terminal device to support CA is a single PA and/or a plurality of PAs. The network device can improve CA resource configuration flexibility by using the foregoing method.

An RF power amplifier is described including a first amplifier and a second amplifier arranged in parallel between an RF power amplifier input and an RF power amplifier output. A phase adjuster adjusts the phase of a signal on at least one of the first amplifier signal path and the second amplifier signal path. A first impedance inverter has a first impedance inverter input coupled to an output of the second amplifier and a first impedance inverter output coupled to the RF power amplifier output. The RF power amplifier is configured to enable at least one of the first amplifier and the second amplifier dependent on an operation mode and the first impedance inverter is configured to modulate the load impedance of the second amplifier in response to the operation mode changing.

An amplifier circuit structure can include an amplifier located in a main path, and a first switch located in a bypass. One end of a second switch is a signal output end of the amplifier circuit structure, and the other end of the second switch is configured to selectively connect to a signal output end of the bypass or a signal output end of the main path. The first and second switches are configured to control their respective operating states when a first instruction is received, such that the main path is connected to the signal input end and the signal output end of the amplifier circuit structure; and to control their respective operating states when a second instruction is received, such that the bypass is connected to the signal input end of the amplifier circuit structure and the signal output end of the amplifier circuit structure.