A matching circuit, a radio frequency front-end power amplification circuit, and a mobile communication device are provided. The matching circuit is configurable for the radio frequency front-end power amplification circuit, including a first impedance matcher, a first bandpass filter, a first wave trap, and a first matching unit. An impedance of the first impedance matcher is a first preset impedance at a first frequency, the first bandpass filter is bridged between a front end of the first impedance matcher and ground, the first bandpass filter enables a signal of the first frequency to pass through, and suppresses at least one of a signal of a second frequency and a signal of third harmonic generation of the first frequency. The second frequency is lower than the first frequency. The first wave trap is bridged between a rear end of the first impedance matcher and the ground.

A high-frequency power amplifier is configured in such a way as to include an input matching circuit, an amplifying element, an output matching circuit, a coupling circuit, a detection circuit, and an output terminal, and in such a way that either the input matching circuit or the output matching circuit has an active element, the detection circuit receives a signal outputted by the coupling circuit and outputs a control voltage into which the detection circuit converts the signal to the active element, and the active element changes the impedance of the active element in accordance with the control voltage outputted by the detection circuit, thereby changing the power of a signal outputted by either the input matching circuit having the active element or the output matching circuit having the active element, to change the power of a signal which the coupling circuit outputs to the output terminal.

A PA module includes a previous stage amplification element to amplify a high-frequency signal, a posterior stage amplification element to amplify the high-frequency signal amplified by the previous stage amplification element, and a variable filter circuit arranged between the previous stage amplification element and the posterior stage amplification element and to vary a pass band and an attenuation band in accordance with a frequency band of the high-frequency signal, in which the variable filter circuit includes a filter portion and switches, the previous stage amplification element, the switches, and the posterior stage amplification element are arranged on a mounting surface of a substrate, the filter portion is stacked and arranged so as to overlap with at least one of the previous stage amplification element, the switches, and the posterior stage amplification element when the substrate is viewed in a plan view.

A bias circuit and a power amplifier circuit are provided in the present disclosure. The bias circuit includes an output node, a power detecting circuit, a first constant voltage bias circuit, and a constant current bias circuit. The output node is configured to provide a bias signal to a power amplifier unit. The output node is further configured to receive an input signal of the power amplifier unit. The power detecting circuit is configured to detect a power of the input signal of the power amplifier unit to provide a first control signal. The first constant voltage bias circuit is configured to selectively provide a first signal to the output node according to the first control signal. The constant current bias circuit provides a second signal to the output node.

An apparatus is disclosed for time-division duplex dynamic transceiver isolation. In an example aspect, the apparatus includes an antenna, a power amplifier circuit including at least one power-amplifying path, a low-noise amplifier, and a time-division duplex interface circuit. The interface includes at least one transmit node coupled to the at least one power-amplifying path, a receive node coupled to the low-noise amplifier, and an antenna node. The antenna node is coupled to the at least one transmit node, the receive node, and the antenna. The interface circuit is configured to connect the at least one transmit node, the receive node, and the antenna node together at both a first time and a second time. The interface circuit is configured to isolate the receive node from the antenna node at the first time and isolate the at least one transmit node from the antenna node at the second time.

An apparatus is disclosed for time-division duplex dynamic transceiver isolation. In an example aspect, the apparatus includes an antenna, a power amplifier circuit including at least one power-amplifying path, a low-noise amplifier, and a time-division duplex interface circuit. The interface includes at least one transmit node coupled to the at least one power-amplifying path, a receive node coupled to the low-noise amplifier, and an antenna node. The antenna node is coupled to the at least one transmit node, the receive node, and the antenna. The interface circuit is configured to connect the at least one transmit node, the receive node, and the antenna node together at both a first time and a second time. The interface circuit is configured to isolate the receive node from the antenna node at the first time and isolate the at least one transmit node from the antenna node at the second time.

An amplifier circuit includes a first adjustable amplification path and a second adjustable amplification path; wherein the first adjustable amplification path and the second adjustable amplification path are configurable in different operating modes selected from a linear operating mode, an efficient operating mode, and an intermediate operating mode to amplify a transmission signal based at least in part on a characteristic of the transmission signal.

Power amplifier module with power supply control. A power amplification control system can include an interface configured to receive a transceiver control signal from a transceiver. The power amplification control system can include a power amplifier control component configured to generate a power amplifier control signal based on the transceiver control signal from the transceiver and a power supply control component configured to generate a power supply control signal based on the transceiver control signal from the transceiver and to generate the power supply control signal based on a local control signal from the power amplifier control component.

Power amplifier module with power supply control. A power amplification control system can include an interface configured to receive a transceiver control signal from a transceiver. The power amplification control system can include a power amplifier control component configured to generate a power amplifier control signal based on the transceiver control signal from the transceiver and a power supply control component configured to generate a power supply control signal based on the transceiver control signal from the transceiver and to generate the power supply control signal based on a local control signal from the power amplifier control component.

A front end circuit architecture that uses the same LNA in each of several frequency bands extending over a wide frequency range. In some embodiments, switched impedance circuits distributed throughout the front end circuit allow selection of the frequency response and impedances that are optimized for particular performance parameters targeted for a desired device characteristic. Such switched impedance circuits tune the output and input impedance match and adjust the gain of the LNA for specific operating frequencies and gain targets. In addition, adjustments to the bias of the LNA can be used to optimize performance trade-offs between the total direct current (DC) power dissipated versus radio frequency (RF) performance. By selecting appropriate impedances throughout the circuit using switched impedance circuits, the LNA can be selectively tuned to operate optimally at a selected bias for operation within selected frequency bands.