Abstract: The present disclosure relates to methods, modules and devices for detecting and preventing occurrence of a saturation state in a power amplifier. A method is disclosed for detecting a saturation condition of a power amplifier, including monitoring a first base current of a first transistor of a cascade transistor pair of the power amplifier and a second base current of a second transistor of the cascade transistor pair. The method can also include generating a current ratio based on comparing the first base current and the second base current. The method can further include determining if the current ratio exceeds or satisfies a threshold value and modifying one or more operating characteristics of the power amplifier in accordance with a determination that the current ratio exceeds or satisfies the threshold value.

Abstract: Power amplifier having staggered cascode layout for enhanced thermal ruggedness. In some embodiments, a radio-frequency (RF) amplifier such as a power amplifier (PA) can be configured to receive and amplify an RF signal. The PA can include an array of cascoded devices connected electrically parallel between an input node and an output node. Each cascoded device can include a common emitter transistor and a common base transistor arranged in a cascode configuration. The array can be configured such that the common base transistors are positioned in a staggered orientation relative to each other.

Abstract: Compression control of cascode power amplifiers. 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 generate a comparison signal. The power amplifier module can include a saturation controller configured to maintain the power amplifier out of saturation based on the comparison signal.

Abstract: According to some implementation, a power amplifier includes a plurality of pairs of transistors, each pair of transistors including a common emitter transistor and a common base transistor arranged in a cascode configuration. The power amplifier further includes electrical connections implemented to connect the plurality of pairs in a parallel configuration between an input node and an output node. According to some implementations, the electrical connections are configured to distribute a collector current to all of the common base transistors to thereby reduce likelihood of damage to one or more common base transistors during a thermal run-away event.

Abstract: Compression control through amplitude adjustment of a radio frequency input signal. A power amplifier module can include a power amplifier. The power amplifier can include a cascode transistor pair. The cascode transistor pair can include a first transistor and a second transistor. The power amplifier module can include a power amplifier bias controller. The power amplifier bias controller can include a current comparator, a saturation controller, and a radio frequency (RF) attenuator. The current comparator can be 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 saturation controller can be configured to supply a reference signal to the RF attenuator based on the comparison value. The RF attenuator can be configured to modify the amplitude of an RF input signal supplied to the power amplifier based at least in part on the reference signal.

Abstract: An RF amplifier module that has a plurality of amplifiers wherein at least one of the amplifiers is powered via an envelope tracking module. The biasing input of at least one of the amplifiers is provided to the first amplifier to power the first amplifier to reduce power consumption. The first amplifier may also be powered via fixed biasing to provide greater stability of the module.

Abstract: Power amplification system with shared common base biasing. A power amplification system can include a plurality of cascode amplifier sections. Each one of the plurality of cascode amplifier sections can include including a first transistor and a second transistor. The power amplification system can include a plurality of common emitter biasing components. Each one of the plurality of common emitter biasing components can be coupled to a base of the first transistor of a respective one of the plurality of cascode amplifier sections and can be controllable to bias the first transistor of the respective one of the plurality of cascode amplifier sections. The power amplification system can include a common base biasing component coupled to a base of the second transistor of each of the plurality of cascode amplifier sections and controllable to bias the second transistor of each of the plurality of cascode amplifier sections.

Abstract: A power amplifier die includes a semiconductor substrate, a power amplifier implemented on the semiconductor substrate, a radio-frequency input configured to receive a radio-frequency input signal having a radio-frequency component and a DC bias component, a bias circuit implemented on the semiconductor substrate, the bias circuit coupled to the power amplifier, and a bias tee circuit implemented on the semiconductor substrate, the bias tee circuit configured to receive the radio-frequency input signal and pass at least a portion of the DC component to the bias circuit and at least a portion of the radio-frequency component to the power amplifier.

Abstract: Compression control through power amplifier load adjustment. 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 power amplifier bias controller including 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.

Abstract: Power amplification system with adjustable common base bias. A power amplification system can include a first transistor having a base coupled to a radio-frequency input. The power amplification can further include a second transistor having an emitter coupled to a collector of the first transistor and having a collector coupled to a radio-frequency output. The power amplification system can include a biasing component configured to apply a fixed biasing signal to the base of the first transistor and to apply an adjustable biasing signal to the base of the second transistor.

Abstract: Circuits and methods for controlling power amplifiers. In some embodiments, a power amplification system can include a first amplification stage configured to operate with a first bias signal, and a second amplification stage configured operate with a second bias signal. The power amplification system can further include a control circuit coupled to the first amplification stage and the second amplification stage. The control circuit can be configured to generate the first bias signal based on the second bias signal. Such a first bias signal can result in the first stage having a gain profile that compensates for either or both of a gain expansion and gain compression of the second amplification stage.

Abstract: According to some implementation, a power amplifier includes a plurality of pairs of transistors, each pair of transistors including a common emitter transistor and a common base transistor arranged in a cascode configuration. The power amplifier further includes electrical connections implemented to connect the plurality of pairs in a parallel configuration between an input node and an output node. According to some implementations, the electrical connections are configured to distribute a collector current to all of the common base transistors to thereby reduce likelihood of damage to one or more common base transistors during a thermal run-away event.

Abstract: Compression control through power amplifier voltage adjustment. 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 power amplifier bias controller. The power amplifier bias controller 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 a voltage converter based on the comparison value. The voltage converter can be configured to modify a supply voltage provided to the power amplifier based at least in part on the reference signal.

Abstract: A power amplifier (PA) system includes an amplifying transistor having a base, a collector, and an emitter. The PA system further includes a radio-frequency (RF) input configured to receive an RF input signal having an RF component and a DC bias component, a bias circuit coupled to the base of the amplifying transistor, and a bias tee circuit configured to receive the RF input signal and pass at least a portion of the DC component to the bias circuit and at least a portion of the RF component to the base of the amplifying transistor.

Abstract: An RF amplifier module that has a plurality of amplifiers wherein at least one of the amplifiers is powered via an envelope tracking module. The biasing input of at least one of the amplifiers is provided to the first amplifier to power the first amplifier to reduce power consumption. The first amplifier may also be powered via fixed biasing to provide greater stability of the module.

Abstract: Compression control of cascode power amplifiers. 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 generate a comparison signal. The power amplifier module can include a saturation controller configured to maintain the power amplifier out of saturation based on the comparison signal.

Abstract: The present disclosure relates to a system for biasing a power amplifier. The system can include a first die that includes a power amplifier circuit and a passive component having an electrical property that depends on one or more conditions of the first die. Further, the system can include a second die including a bias signal generating circuit that is configured to generate a bias signal based at least in part on measurement of the electrical property of the passive component of the first die.

Abstract: One aspect of this disclosure is a power amplifier module that includes a first die including a power amplifier and a passive component, the power amplifier including a bipolar transistor having a collector, a base abutting the collector, and an emitter, the collector having a doping concentration of at least about 3×1016 cm?3 at an interface with the base, the collector also having a grading in which doping concentration increases away from the base; and a second die including a bias circuit configured to generate a bias signal based at least partly on an indication of an electrical property of the passive component of the first die and to provide the bias signal to the power amplifier. Other embodiments of the module are provided along with related methods and components thereof.

Abstract: One aspect of this disclosure is a power amplifier module that includes a first die including a power amplifier and a passive component, the power amplifier including a bipolar transistor having a collector, a base abutting the collector, and an emitter, the collector having a doping concentration of at least about 3×1016 cm?3 at an interface with the base, the collector also having a grading in which doping concentration increases away from the base; and a second die including a bias circuit configured to generate a bias signal based at least partly on an indication of an electrical property of the passive component of the first die and to provide the bias signal to the power amplifier. Other embodiments of the module are provided along with related methods and components thereof.

Abstract: Doherty power amplifier having reduced size. In some embodiments, a power amplification system can include a supply system configured to provide a high-voltage supply signal, and a Doherty power amplifier configured to receive the high-voltage supply signal and amplify a radio-frequency (RF) signal. The power amplification system can further include an output path configured to receive and route the amplified RF signal to a filter. The output path can be substantially free of an impedance transformation circuit.