A power amplifier system comprises an envelope tracker configured to generate a supply voltage that changes in relation to an envelope of a radio frequency signal, a power amplifier configured to amplify the radio frequency signal, and an adaptation circuit configured to adapt the supply voltage to provide operating power to the power amplifier. The adaptation circuit includes at least one Gallium Nitride field-effect-transistor configured to generate the operating power in response to an increased swing of the supply voltage and at least one linearizing circuit configured to linearize an operation of the Gallium Nitride field-effect-transistor.

Apparatus and methods for power amplifier envelope tracking systems with automatic control of a slew rate and a mode of an error amplifier of the envelope tracking system. The envelope tracker can include a signal bandwidth detection circuit that processes the envelope signal to generate a detected bandwidth signal, and a control circuit that controls the slew rate of the error amplifier based on the detected signal bandwidth.

Provided is an electronic device that includes a communication processor; a transceiver electrically connected to the communication processor; a first power amplifier electrically connected to the transceiver; a first antenna electrically connected to the first power amplifier; and a first supply adjustor electrically connected to the communication processor and the first power amplifier. The communication processor can be set to perform a first determination about whether a carrier bandwidth part of a first signal transmitted through the first antenna exceeds a first threshold value, perform a second determination about whether the power of the first signal exceeds a second threshold value, select a first tracking mode as an envelope tracking mode or an average power tracking mode on the basis of at least a portion of the first determination and the second determination, and control the first supply adjustor using the selected first tracking mode.

Apparatus and methods for power detection with enhanced dynamic range are provided. In certain embodiments, a front end system includes a power amplifier that amplifies a radio frequency (RF) input signal to generate an RF output signal, a directional coupler that generates a sensed RF signal based on sensing the RF output signal from the power amplifier, and a power detector that processes the sensed RF signal to generate a detection signal indicating an output power of the power amplifier. Additionally, the power detector includes two or more detection paths providing different amounts of gain to the sensed RF signal from the directional coupler.

Doherty power amplifiers with coupled line combiners are provided herein. In certain embodiments, a power amplifier system includes a carrier amplifier having a carrier output that provides a first radio frequency signal, a peaking amplifier having a peaking output that provides a second radio frequency signal, and a coupled line combiner including a first conductor line connected to the peaking output, a second conductor line electromagnetically coupled to the first conductor line, a third conductor line connected to the carrier output, and a fourth conductor line electromagnetically coupled to the third conductor line and in series with the second conductor line. The power amplifier system further includes an inductor in series with the fourth conductor line and the second conductor line and operable to provide a radio frequency output signal to an output terminal.

Embodiments described herein relate to an envelope tracking system that uses a single-bit digital signal to encode an analog envelope tracking control signal, or envelope tracking signal for brevity. In certain embodiments, the envelope tracking system can estimate or measure the amplitude of the baseband signal. The envelope tracking system can further estimate the amplitude of the envelope of the RF signal. The system can convert the amplitude of the envelope signal to a single-bit digital signal, typically at a higher, oversample rate. The single-bit digital signal can be transmitted in, for example, a low-voltage differential signaling (LVDS) format, from a transceiver to an envelope tracker. An analog-to-digital converter (ADC or A/D) can convert the single-bit digital signal back to an analog envelope signal. Moreover, a driver can increase the power of the A/D output envelope signal to produce an envelope-tracking supply voltage for a power amplifier.

A power management circuit supporting phase correction in an analog signal with reduced physical pins is disclosed. The power management circuit includes a power amplifier circuit configured to amplify an analog signal having a time-variant power envelope based on a modulated voltage. The power management circuit also includes an envelope tracking integrated circuit (ETIC) configured to generate the modulated voltage and a modulated phase correction voltage to thereby cause a phase change in the analog signal. The ETIC receives a modulated differential signal that includes a common signal and a differential signal and generates the modulated phase correction voltage and the modulated voltage based on the common signal and the differential signal, respectively. By modulating the common signal and the differential signal into the modulated differential signal, it is possible to reduce physical pins in the ETIC to thereby reduce cost and footprint of the power management circuit.

A power amplifier comprises a first amplification stage having an input terminal receiving a radio frequency (RF) signal to be amplified and having a first coupling unit, a second amplification stage outputting an amplified radio frequency signal and having a second coupling unit and a third coupling unit providing RF feedback to the input terminal of the first amplification stage through an RF feedback path, the second coupling unit being coupled to the first coupling unit, and the third coupling unit being coupled to the first coupling unit.

A power supply switch circuit includes: a first switch to switch supply of a first power supply voltage to a power supply terminal of a power amplifier; a control voltage generator to generate a first control voltage through a charge pump operation, and to control the charge pump operation by comparing the first power supply voltage to a first voltage, which is a voltage of the power supply terminal; and a switch controller to generate a switching driving signal to control the first switch using the first control voltage.

An electronic device and method thereof of are provided to prevent burnout due to overcurrent. An electronic device includes a power amplifier configured to amplify a transmission signal; a battery configured to provide a bias voltage to the at least one power amplifier; and an overcurrent protection circuit configured to prevent overcurrent from flowing through the power amplifier. The overcurrent protection circuit includes a configurer configured to configure a reference current value, based on the power amplifier; a measurer configured to measure a bias current value due to the bias voltage; a comparator configured to compare the measured bias current value with the reference current value; and a controller configured to recognize overcurrent flowing through the power amplifier and control provision of the bias voltage, based on a result of the comparison.