Power amplifier (PA) packages, such as Doherty PA packages, containing multi-path integrated passive devices (IPDs) are disclosed. In embodiments, the PA package includes a package body through which first and second signal amplification paths extend, a first amplifier die within the package body and positioned in the first signal amplification path, and a second amplifier die within the package body and positioned in the second signal amplification path. A multi-path IPD is further contained in the package body. The multi-path IPD includes a first IPD region through which the first signal amplification path extends, a second IPD region through which the second signal amplification path extends, and an isolation region formed in the IPD substrate a location intermediate the first IPD region and the second IPD region.

Power amplifier (PA) packages, such as Doherty PA packages, containing multi-path integrated passive devices (IPDs) are disclosed. In embodiments, the PA package includes a package body through which first and second signal amplification paths extend, a first amplifier die within the package body and positioned in the first signal amplification path, and a second amplifier die within the package body and positioned in the second signal amplification path. A multi-path IPD is further contained in the package body. The multi-path IPD includes a first IPD region through which the first signal amplification path extends, a second IPD region through which the second signal amplification path extends, and an isolation region formed in the IPD substrate a location intermediate the first IPD region and the second IPD region.

Systems and methods are disclosed for on-chip harmonic filtering for radio frequency (RF) communications. For disclosed embodiments, a filter circuit is coupled between a first internal node and a connection pad for an integrated circuit. The filter circuit includes a first inductance, a variable capacitance, and a second inductance. The capacitance amount for the variable capacitance is controlled to tune filtering for the filter circuit to a harmonic of a frequency for a transmit output signal. A power amplifier outputs the transmit output signal to the connection pad without passing through the filter circuit. The filter circuit filters the harmonic of the frequency for the transmit output signal, shunting harmonic current to ground. For one embodiment, the filtered harmonic is a third harmonic of the transmit frequency. For one embodiment, the transmit output signal has an output power greater than or equal to 15 dBm.

A radio frequency module includes: a module board that includes a first principal surface and a second principal surface on opposite sides of the module board; a power amplifier configured to amplify a transmission signal; a first circuit component; and a power amplifier (PA) control circuit configured to control the power amplifier. The power amplifier and the PA control circuit are stacked on the first principal surface, and the first circuit component is disposed on the second principal surface.

Systems, methods, and devices relate to tunable circuits for multimode power amplification. For example, a variable-gain amplification system can include an amplifier configured to provide an amplified signal and to selectively operate in at least a first gain mode and a second gain mode. The variable-gain amplification system can also include a tunable circuit configured to receive the amplified signal from the amplifier and to provide an output signal. The tunable circuit can be configured to implement a first turn ratio for the first gain mode and a second turn ratio for the second gain mode.

Systems, methods, and devices relate to tunable circuits for multimode power amplification. For example, a variable-gain amplification system can include an amplifier configured to provide an amplified signal and to selectively operate in at least a first gain mode and a second gain mode. The variable-gain amplification system can also include a tunable circuit configured to receive the amplified signal from the amplifier and to provide an output signal. The tunable circuit can be configured to implement a first turn ratio for the first gain mode and a second turn ratio for the second gain mode.

A power amplifier circuit includes an amplifier circuit, a bias circuit, a detector, and a control circuit. The amplifier circuit includes a first bipolar transistor. The bias circuit includes an emitter follower. The emitter follower includes a second bipolar transistor and supplies a bias current to the base of the first bipolar transistor. The detector detects the voltage of a power supply terminal connected to the collector of the first bipolar transistor. The control circuit includes a current limiting circuit disposed between a battery terminal and the collector of the second bipolar transistor. The control circuit changes an upper limit value of a control current to be supplied to the collector of the second bipolar transistor, based on the voltage detected by the detector.

A power amplifier circuit includes an amplifier circuit, a bias circuit, a detector, and a control circuit. The amplifier circuit includes a first bipolar transistor. The bias circuit includes an emitter follower. The emitter follower includes a second bipolar transistor and supplies a bias current to the base of the first bipolar transistor. The detector detects the voltage of a power supply terminal connected to the collector of the first bipolar transistor. The control circuit includes a current limiting circuit disposed between a battery terminal and the collector of the second bipolar transistor. The control circuit changes an upper limit value of a control current to be supplied to the collector of the second bipolar transistor, based on the voltage detected by the detector.

A thin-film resistive element includes: a first electrode that is formed with a conductor formed in an annular shape in a planar view; a second electrode that is formed with a conductor disposed at a distance from the first electrode in a region surrounded by the first electrode; and a thin-film resistor that is electrically connected to the first electrode and the second electrode.

A thin-film resistive element includes: a first electrode that is formed with a conductor formed in an annular shape in a planar view; a second electrode that is formed with a conductor disposed at a distance from the first electrode in a region surrounded by the first electrode; and a thin-film resistor that is electrically connected to the first electrode and the second electrode.