A power control device includes: a controller configured to, when a frequency band selection instruction is detected, determine a target frequency band from the frequency band selection instruction in response to the frequency band selection instruction; and to determine, based on the target frequency band, a target inter-stage matching circuit of a path from a plurality of inter-stage matching circuits; a driving element configured to, when an input power signal within the target frequency band is received, pre-amplify the input power signal to obtain a pre-amplified power signal and transmit the pre-amplified power signal to the target inter-stage matching circuit; the target inter-stage matching circuit configured to process the pre-amplified power signal to obtain an intermediate input signal and provide the intermediate input signal to a power stage amplification circuit; the power stage amplification circuit configured to amplify the intermediate input signal to obtain an output power signal.

A radio frequency power amplifier circuit includes a controllable attenuation circuit, an input matching circuit, a drive amplification circuit, an inter-stage matching circuit, a power amplification circuit and an output matching circuit connected in sequence, and respectively configured to switch between a negative gain mode and a non-negative gain mode of the radio frequency power amplifier circuit based on a mode control signal, match the impedance between the controllable attenuation circuit and the drive amplification circuit, amplify a signal, configured to match the impedance between the drive amplification circuit and the power amplification circuit, amplify a signal, and match the impedance between the radio frequency power amplifier circuit and a post-stage circuit. A feedback circuit is connected across the drive amplification circuit, and is configured to adjust a gain.

A power amplifier circuit includes a lower transistor having a first terminal, a second terminal connected to ground, and a third terminal, wherein a first power supply voltage is supplied to the first terminal, and an input signal is supplied to the third terminal; a first capacitor; an upper transistor having a first terminal, a second terminal connected to the first terminal of the lower transistor via the first capacitor, and a third terminal, wherein a second power supply voltage is supplied to the first terminal, an amplified signal is outputted to an output terminal from the first terminal, and a driving voltage is supplied to the third terminal; a first inductor that connects the second terminal of the upper transistor to ground; a voltage regulator circuit; and at least one termination circuit that short-circuits an even-order harmonic or odd-order harmonic of the amplified signal to ground potential.

A semiconductor-on-insulator die can include a power amplifier configured to amplify a radio frequency input signal having a fundamental frequency. The die can further include an output matching circuit including first and second second-order harmonic rejection circuits configured to resonate at about two times the fundamental frequency and a third order harmonic rejection circuit configured to resonate at about three times the fundamental frequency.

The present disclosure relates to devices and methods for detecting and preventing occurrence of a saturation state in a power amplifier. A power amplifier module can include a power amplifier including a cascode transistor pair. The cascode transistor pair can include a first transistor and a second transistor. The power amplifier module can include a current comparator configured to compare a first base current of the first transistor and a second base current of the second transistor to obtain a comparison value. The power amplifier module can include a saturation controller configured to supply a reference signal to an impedance matching network based on the comparison value. The impedance matching network can be configured to modify a load impedance of a load line in electrical communication with the power amplifier based at least in part on the reference signal.

The present disclosure relates to devices and methods for detecting and preventing occurrence of a saturation state in a power amplifier. A power amplifier module can include a power amplifier including a cascode transistor pair. The cascode transistor pair can include a first transistor and a second transistor. The power amplifier module can include a current comparator configured to compare a first base current of the first transistor and a second base current of the second transistor to obtain a comparison value. The power amplifier module can include a saturation controller configured to supply a reference signal to an impedance matching network based on the comparison value. The impedance matching network can be configured to modify a load impedance of a load line in electrical communication with the power amplifier based at least in part on the reference signal.

Example embodiments relate to amplifiers having improved stability. One example amplifier includes a conductive substrate, an input terminal arranged spaced apart from the conduct substrate, a first bondwire attachment structure electrically connected to or integrally formed with the input terminal, a first input matching capacitor having a non-grounded terminal and a grounded terminal, a second bondwire attachment structure electrically connected to the non-grounded terminal of the first input matching capacitor, a first semiconductor die on which a radiofrequency power transistor is arranged that has an output electrically connected to a fourth bondwire attachment structure, an output matching capacitor having a non-grounded terminal and a grounded terminal (the non-grounded terminal being electrically connected to a fifth bondwire attachment structure), an output terminal arranged spaced apart from the conductive substrate, a sixth bondwire attachment structure electrically connected to or integrally formed with the output terminal, and multiple bondwire assemblies.

Apparatus and methods for reconfigurable power amplifiers are disclosed. In certain embodiments, a mobile device includes a transceiver configured to generate a first radio frequency signal of a first frequency band and a second radio frequency signal of a second frequency band, and a front-end system including a push-pull power amplifier configured to selectively amplify one of the first radio frequency signal or the second radio frequency signal based on a band control signal. The push-pull power amplifier includes an input balun, an output balun, and a pair of amplifiers coupled between the input balun and the output balun. The band control signal is operable to control an input capacitance of the pair of amplifiers.

Apparatus and methods for reconfigurable power amplifiers are disclosed. In certain embodiments, a mobile device includes a transceiver configured to generate a first radio frequency signal of a first frequency band and a second radio frequency signal of a second frequency band, and a front-end system including a push-pull power amplifier configured to selectively amplify one of the first radio frequency signal or the second radio frequency signal based on a band control signal. The push-pull power amplifier includes an input balun, an output balun, and a pair of amplifiers coupled between the input balun and the output balun. The band control signal is operable to control an input capacitance of the pair of amplifiers.

A microwave amplifier having a load network which provides more efficient amplification of a low power microwave frequency signal. The amplifier comprises a transistor and a load network coupled to the transistor output to shape a waveform of an amplified microwave signal at the transistor current source plane. The load network comprises: a fundamental matching network to provide impedance matching at a fundamental frequency; a half-wave transmission line for a second harmonic frequency disposed between the transistor output and the fundamental matching network; a quarter-wave stub and a five-quarter-wave stub for a third harmonic frequency arranged on the half-wave transmission line to provide an open circuit condition at the third harmonic; and a quarter-wave stub for the second harmonic frequency and a quarter-wave stub for the fundamental frequency, arranged on the half-wave transmission line to provide a short circuit condition at the second harmonic frequency.