Integrated Doherty power amplifiers are provided herein. In certain implementations, a Doherty power amplifier includes a carrier amplification stage that generates a carrier signal, a peaking amplification stage that generates a peaking signal, and an antenna structure that combines the carrier signal and the peaking signal. The antenna structure radiates a transmit wave in which the carrier signal and the peaking signal are combined with a phase shift.

A distributed power management circuit is provided. In embodiments disclosed herein, the distributed power management circuit can achieve multiple performance enhancing objectives simultaneously. More specifically, the distributed power management circuit can be configured to switch a modulated voltage from one voltage level to another within a very short switching window, reduce in-rush current required for switching the modulated voltage, and minimize a ripple in the modulated voltage, all at same time. As a result, the distributed power management circuit can be provided in a wireless device (e.g., smartphone) to enable very fast voltage switching across a wide modulation bandwidth (e.g., 400 MHz) with reduced power consumption and voltage distortion.

Disclosed are apparatuses and methods for fabricating the apparatuses. In one aspect, an apparatus includes a high-power die mounted on a backside of a package substrate. A heat transfer layer is disposed on the backside of the high-power die. A plurality of heat sink interconnects is coupled to the heat transfer layer. The plurality of heat sink interconnects is located adjacent the high-power die in a horizontal direction.

Disclosed are apparatuses and methods for fabricating the apparatuses. In one aspect, an apparatus includes a high-power die mounted on a backside of a package substrate. A heat transfer layer is disposed on the backside of the high-power die. A plurality of heat sink interconnects is coupled to the heat transfer layer. The plurality of heat sink interconnects is located adjacent the high-power die in a horizontal direction.

Apparatus and methods for an improved-efficiency Doherty amplifier are described. The Doherty amplifier may include a two-stage peaking amplifier that transitions from an off state to an on state later and more rapidly than a single-stage peaking amplifier used in a conventional Doherty amplifier. The improved Doherty amplifier may operate at higher gain values than a conventional Doherty amplifier, with no appreciable reduction in signal bandwidth.

The present disclosure relates to systems and methods for operating transceiver circuitry to transmit or receive signals on various frequency ranges. To do so, a transmitter or a receiver of the transceiver circuitry is selectively coupled to or uncoupled from an antenna of the transceiver circuitry. Additionally, radio frequency filters may be individually or collectively coupled to and/or uncoupled from the antenna to filter different frequencies in the transmitting or receiving signals.

The present disclosure relates to systems and methods for operating transceiver circuitry to transmit or receive signals on various frequency ranges. To do so, a transmitter or a receiver of the transceiver circuitry is selectively coupled to or uncoupled from an antenna of the transceiver circuitry. Additionally, radio frequency filters may be individually or collectively coupled to and/or uncoupled from the antenna to filter different frequencies in the transmitting or receiving signals.

Systems and methods for extending operation of radio-frequency (RF) power amplifiers. In some embodiments, a method for fabricating a wireless device can be implemented. The method includes providing a flash LED driver and a radio-frequency block, coupling an output of the flash LED driver and the radio-frequency block and coupling the flash LED driver with a controller to allow the flash LED driver to provide boosted voltage to the radio-frequency block under a selected condition. Accordingly, the power amplifier can operate for a longer time when powered by a battery.

An amplifier module is provided. The amplifier module includes a multi-layer printed circuit board (PCB). A first power transistor die is mounted at a top surface of the multi-layer PCB. A second power transistor die is mounted at the top surface of the multi-layer PCB. An impedance inversion element is coupled between an output of the first power transistor die and an output of the second power transistor die. A combining node is formed at the output of the second power transistor die. A stub circuit including a transmission line element is coupled at the combining node.

An amplifier module is provided. The amplifier module includes a multi-layer printed circuit board (PCB). A first power transistor die is mounted at a top surface of the multi-layer PCB. A second power transistor die is mounted at the top surface of the multi-layer PCB. An impedance inversion element is coupled between an output of the first power transistor die and an output of the second power transistor die. A combining node is formed at the output of the second power transistor die. A stub circuit including a transmission line element is coupled at the combining node.