Abstract: Systems, devices and methods related to stacked band selection switch devices. In some embodiments, an RF module can include a packaging substrate and a power amplifier (PA) assembly implemented on a PA die mounted on the packaging substrate. The RF module can further include an output matching network (OMN) device mounted on the packaging substrate and a band selection switch device mounted on the OMN device. The OMN device can be configured to provide output matching functionality for at least a portion of the PA assembly.

Abstract: Doherty power amplifier combiner with tunable impedance termination circuit. A signal combiner can include a balun transformer circuit having a first coil and a second coil. The first coil can be implemented between a first port and a second port. The second coil can be implemented between a third port and a fourth port. The first port and the third port can be coupled by a first capacitor. The second port and fourth port can be coupled by a second capacitor. The first port can be configured to receive a first signal. The fourth port can be configured to receive a second signal. The second port can be configured to yield a combination of the first signal and the second signal. The signal combiner can include a termination circuit that couples the third port to a ground. The termination circuit can include a tunable impedance circuit.

Abstract: Power amplifier bias circuit. A power amplifier bias circuit can include an emitter follower device and an emitter follower mirror device coupled to form a mirror configuration. The emitter follower device can be configured to provide a bias signal for a power amplifier at an output port. The power amplifier bias circuit can include a reference device configured to mirror an amplifying device of the power amplifier. The emitter follower mirror device can be configured to provide a mirror bias signal to the reference device.

Abstract: An amplifier architecture can include an input circuit for splitting a signal into first and second portions, and carrier and peaking amplification paths for receiving the first and second portions. The architecture can further include an output circuit having a balun transformer circuit with first and second coils, with the first coil between first and second ports, the second coil between third and fourth ports, the first and third ports coupled by a first capacitance, and the second and fourth ports coupled by a second capacitance. The first port can receive a first signal from the carrier amplification path, and the fourth port can receive a second signal from the peaking amplification path. The second port can provide a combination of the first signal and the second signal as an amplified signal. A termination circuit can be provided to couple the third port to a ground.

Abstract: Systems and methods related to linear load modulated power amplifiers. A power amplifier (PA) system can include an input circuit configured to receive a radio-frequency (RF) signal and split the RF signal into a first portion and a second portion. The PA system can further include a Doherty amplifier circuit including a carrier amplifier coupled to the input circuit to receive the first portion and a peaking amplifier coupled to the input circuit to receive the second portion. The first portion and the second portion can have different phases and/or different powers. The PA system can further include an output circuit coupled to the Doherty amplifier circuit. The output circuit can be configured to combine outputs of the carrier amplifier and the peaking amplifier to yield an amplified RF signal.

Abstract: Impedance matching circuit for radio-frequency amplifier. In some embodiments, an impedance matching circuit can include a primary metal trace having a first end configured to be capable of being coupled to a voltage source for the power amplifier, and a second end configured to be capable of being coupled to an output of the power amplifier. The impedance matching circuit can further include a secondary metal trace having first end coupled to the second end of the primary metal trace, and a second end configured to be capable of being coupled to an output node. The impedance matching circuit can further include a capacitance implemented between the first and second ends of the secondary metal trace, and be configured to trap a harmonic associated with an amplified signal at the output of the power amplifier.

Abstract: Systems and methods related to linear and efficient broadband power amplifiers are disclosed. In some embodiments, a method for amplifying a radio-frequency signal includes providing a Doherty amplifier circuit having a carrier amplification path and a peaking amplification path. The method includes receiving an radio-frequency signal and splitting the radio-frequency signal into a first portion and a second portion, the first portion provided to the carrier amplification path, the second portion provided to the peaking amplification path. The method further includes combining, using a balance to unbalance circuit, outputs of the carrier amplification path and the peaking amplification path to yield an amplified radio-frequency signal.

Abstract: Systems, devices and methods related to stacked band selection switch devices. In some embodiments, an RF module can include a packaging substrate and a power amplifier (PA) assembly implemented on a PA die mounted on the packaging substrate. The RF module can further include an output matching network (OMN) device mounted on the packaging substrate and a band selection switch device mounted on the OMN device. The OMN device can be configured to provide output matching functionality for at least a portion of the PA assembly.

Abstract: Power amplification system is disclosed. A power amplification system can include a Class-E push-pull amplifier including a transformer balun. The power amplification can further include a reactance compensation circuit coupled to the transformer balun. In some embodiments, the reactance compensation circuit is configured to reduce variation over frequency of a fundamental load impedance of the power amplification system.

Abstract: Doherty power amplifier combiner with tunable impedance termination circuit. A signal combiner can include a balun transformer circuit having a first coil and a second coil. The first coil can be implemented between a first port and a second port. The second coil can be implemented between a third port and a fourth port. The first port and the third port can be coupled by a first capacitor. The second port and fourth port can be coupled by a second capacitor. The first port can be configured to receive a first signal. The fourth port can be configured to receive a second signal. The second port can be configured to yield a combination of the first signal and the second signal. The signal combiner can include a termination circuit that couples the third port to a ground. The termination circuit can include a tunable impedance circuit.

Abstract: Doherty power amplifier with tunable input network. An input network for a Doherty power amplifier can include a splitter circuit configured to receive a radio-frequency (RF) signal and split the RF signal into a first portion along a first path to a carrier amplifier of the Doherty power amplifier and a second portion along a second path to a peaking amplifier of the Doherty power amplifier. The input network can further include a tunable input circuit implemented along either or both of the first path and second path. The tunable input circuit can be configured to provide control of the amplitude and phase of either or both of the first portion and second portion.

Abstract: Disclosed are devices and methods related to autotransformer-based impedance matching for radio-frequency (RF) applications. In some embodiments, an impedance matching device can include a primary metal trace and a secondary metal trace, each having a respective number of turns. Such metal traces can be interconnected to form an autotransformer with the primary metal trace and the secondary metal trace being in respective planes separated by a selected distance. Such an autotransformer can be utilized to, for example, facilitate impedance matching of an amplified RF signal from a power amplifier (PA). In some embodiments, the impedance matching device can be implemented as an integrated passive device (IPD) mountable on a packaging substrate. Such an IPD can be configured to allow stacking of another component on the IPD to yield a number of desirable features in products such as RF modules.

Abstract: Systems, devices and methods related to stacked band selection switch devices. In some embodiments, an RF module can include a packaging substrate and a power amplifier (PA) assembly implemented on a PA die mounted on the packaging substrate. The RF module can further include an output matching network (OMN) device mounted on the packaging substrate and a band selection switch device mounted on the OMN device. The OMN device can be configured to provide output matching functionality for at least a portion of the PA assembly.

Abstract: Reference circuits for biasing radio frequency electronics are provided herein. In certain implementations, a gallium arsenide die includes a power amplifier configured to provide amplification to a signal, a reference voltage circuit including an output terminal that provides a reference voltage, and a mirror circuit configured to bias the power amplifier based on the reference voltage. The reference voltage circuit includes a bipolar transistor, a field effect transistor, and a circuit portion that generates a voltage that is proportional to absolute temperature. The reference voltage circuit generates the reference voltage based on a sum of a base-to-emitter voltage of the bipolar transistor, a turn-on voltage of the field effect transistor, and the voltage that is proportional to absolute temperature.

Abstract: Systems and methods related to linear and efficient broadband power amplifiers are disclosed. In some embodiments, a method for amplifying a radio-frequency signal includes providing a Doherty amplifier circuit having a carrier amplification path and a peaking amplification path. The method includes receiving an radio-frequency signal and splitting the radio-frequency signal into a first portion and a second portion, the first portion provided to the carrier amplification path, the second portion provided to the peaking amplification path. The method further includes combining, using a balance to unbalance circuit, outputs of the carrier amplification path and the peaking amplification path to yield an amplified radio-frequency signal.

Abstract: An amplifier architecture can include an input circuit for splitting a signal into first and second portions, and carrier and peaking amplification paths for receiving the first and second portions. The architecture can further include an output circuit having a balun transformer circuit with first and second coils, with the first coil between first and second ports, the second coil between third and fourth ports, the first and third ports coupled by a first capacitance, and the second and fourth ports coupled by a second capacitance. The first port can receive a first signal from the carrier amplification path, and the fourth port can receive a second signal from the peaking amplification path. The second port can provide a combination of the first signal and the second signal as an amplified signal. A termination circuit can be provided to couple the third port to a ground.

Abstract: Reference circuits for biasing radio frequency electronics are provided herein. In certain implementations, a gallium arsenide die includes a power amplifier configured to provide amplification to a signal, a reference voltage circuit including an output terminal that provides a reference voltage, and a mirror circuit configured to bias the power amplifier based on the reference voltage. The reference voltage circuit includes a bipolar transistor, a field effect transistor, and a circuit portion that generates a voltage that is proportional to absolute temperature. The reference voltage circuit generates the reference voltage based on a sum of a base-to-emitter voltage of the bipolar transistor, a turn-on voltage of the field effect transistor, and the voltage that is proportional to absolute temperature.

Abstract: Circuits, devices and methods related to combiners for Doherty power amplifiers. A signal combiner can include a balun transformer circuit having a first coil and a second coil. The first coil can be implemented between a first port and a second port. The second coil can be implemented between a third port and a fourth port. The first port and the third port can be coupled by a first capacitance. The second port and the fourth port can be coupled by a second capacitance. The first port can be configured to receive a first signal. The fourth port can be configured to receive a second signal. The second port can be configured to yield a combination of the first signal and the second signal. The signal combiner can include a termination circuit that couples the third port to a ground.

Abstract: Systems and methods related to linear and efficient broadband power amplifiers. A power amplifier (PA) system can include an input circuit configured to receive a radio-frequency (RF) signal and split the RF signal into a first portion and a second portion. The PA system can further include a Doherty amplifier circuit including a carrier amplification path coupled to the input circuit to receive the first portion and a peaking amplification path coupled to the input circuit to receive the second portion. The PA system can further include an output circuit coupled to the Doherty amplifier circuit. The output circuit can include a balance to unbalance (BALUN) circuit configured to combine outputs of the carrier amplification path and the peaking amplification path to yield an amplified RF signal.

Abstract: Systems, devices and methods related to stacked band selection switch devices. In some embodiments, an RF module can include a packaging substrate and a power amplifier (PA) assembly implemented on a PA die mounted on the packaging substrate. The RF module can further include an output matching network (OMN) device mounted on the packaging substrate and a band selection switch device mounted on the OMN device. The OMN device can be configured to provide output matching functionality for at least a portion of the PA assembly.