Abstract: Power amplification system with adaptive bias control. In some embodiments a power amplification system includes a power amplifier including a radio-frequency (RF) input terminal for receiving an RF signal, an RF output terminal for providing an amplified RF signal, a supply voltage terminal for receiving a power amplifier supply voltage to power the power amplifier, and one or more bias terminals for receiving one or more bias signals. The power amplification system also includes a bias controller configured to provide the one or more bias signals to the one or more bias terminals, at least one of the one or more bias signals being based on the power amplifier supply voltage.

Abstract: A power amplifier module can include one or more switches, a coupler module, input signal pins, and a controller having first and second output terminals. The input signal pins can receive a voltage input/output signal, a clock input signal, and a data input signal. The controller can (i) set a mode of the one or more switches using a synchronous communication protocol in which the controller outputs a synchronous clock signal on the first output terminal and a data signal on the second output terminal, when the power amplifier module is in a first operating mode, or (ii) set a mode of the coupler module using an asynchronous communication protocol in which the controller outputs a first asynchronous control signal on the first output terminal and a second asynchronous control signal on the second output terminal, when the power amplifier module is in a second operating mode.

Abstract: Apparatus and methods for level shifting in a radio frequency system are provided. In certain configurations, a radio frequency system includes a level shifter operable to provide level shifting to an input signal. The level shifter is biased by a bias voltage and powered by a supply voltage and a charge pump voltage. The radio frequency system further includes a charge pump configured to provide the charge pump voltage and to receive a mode signal operable to enable the charge pump in a first state and to disable the charge pump in a second state. The radio frequency system further includes a level shifter control circuit configured to control the bias voltage to track the charge pump voltage when the mode signal is in the first state, and to control the bias voltage with the supply voltage when the mode signal is in the second state.

Abstract: Power amplifier having biasing with selectable bandwidth. In some embodiments, a power amplifier can include an amplifying transistor having a base for receiving a signal to be amplified, and a bias circuit configured to bias the amplifying transistor. The bias circuit can include a reference transistor having a base coupled to the base of the amplifying transistor and a collector coupled to a reference current source. The bias circuit can further include a coupling circuit that couples the collector and the base of the reference transistor. The coupling circuit can include a switchable element configured to allow the coupling circuit to be in a first state to provide a first bandwidth for the bias circuit or a second state to provide a second bandwidth for the bias circuit.

Abstract: A power amplifier module can include one or more switches, a coupler module, input signal pins, and a controller having first and second output terminals. The input signal pins can receive a voltage input/output signal, a clock input signal, and a data input signal. The controller can (i) set a mode of the one or more switches using a synchronous communication protocol in which the controller outputs a synchronous clock signal on the first output terminal and a data signal on the second output terminal, when the power amplifier module is in a first operating mode, or (ii) set a mode of the coupler module using an asynchronous communication protocol in which the controller outputs a first asynchronous control signal on the first output terminal and a second asynchronous control signal on the second output terminal, when the power amplifier module is in a second operating mode.

Abstract: Power amplification system with adaptive bias control. In some embodiments a power amplification system includes a power amplifier including a radio-frequency (RF) input terminal for receiving an RF signal, an RF output terminal for providing an amplified RF signal, a supply voltage terminal for receiving a power amplifier supply voltage to power the power amplifier, and one or more bias terminals for receiving one or more bias signals. The power amplification system also includes a bias controller configured to provide the one or more bias signals to the one or more bias terminals, at least one of the one or more bias signals being based on the power amplifier supply voltage.

Abstract: Apparatus and methods for level shifting in a radio frequency system are provided. In certain configurations, a radio frequency system includes a level shifter operable to provide level shifting to an input signal. The level shifter is biased by a bias voltage and powered by a supply voltage and a charge pump voltage. The radio frequency system further includes a charge pump configured to provide the charge pump voltage and to receive a mode signal operable to enable the charge pump in a first state and to disable the charge pump in a second state. The radio frequency system further includes a level shifter control circuit configured to control the bias voltage to track the charge pump voltage when the mode signal is in the first state, and to control the bias voltage with the supply voltage when the mode signal is in the second state.

Abstract: A power amplifier module can include one or more switches, a coupler module, input signal pins, and a controller having first and second output terminals. The input signal pins can receive a voltage input/output signal, a clock input signal, and a data input signal. The controller can (i) set a mode of the one or more switches using a synchronous communication protocol in which the controller outputs a synchronous clock signal on the first output terminal and a data signal on the second output terminal, when the power amplifier module is in a first operating mode, or (ii) set a mode of the coupler module using an asynchronous communication protocol in which the controller outputs a first asynchronous control signal on the first output terminal and a second asynchronous control signal on the second output terminal, when the power amplifier module is in a second operating mode.

Abstract: Circuitry, modules and devices for integrating front-end carrier aggregation architecture, are disclosed. In some embodiments, a front-end architecture includes a switching assembly configured to provide switching for two or more frequency bands. In some embodiments, the switching assembly includes at least one coupler configured to couple a signal associated with the switching assembly. The front-end architecture can also include a diplexer circuit including a first filter configured to pass a first frequency band, a second filter configured to pass a second frequency band, and a first electrostatic discharge network configured to dissipate electrostatic energy associated with the first and second frequency bands from the front-end architecture.

Abstract: Systems, circuits and methods related to low power efficiency improvement in multi-mode multi-band power amplifiers. In some embodiments, a power-amplifier (PA) system can include a first amplification path having one or more PAs configured to generate a high power radio-frequency (RF) signal from an input RF signal when in a high power mode. The PA system can further include a second amplification path having one or more PAs configured to generate a low power RF signal from the input RF signal when in a low power mode. The PA system can further include a switching circuit coupled to the first amplification path and the second amplification path. The switching circuit can be configured to allow amplification of the input RF signal through the first amplification path in the high power mode or the second amplification path in the low power mode.

Abstract: Apparatus and methods for controlling radio frequency (RF) switches are disclosed. Provided herein are apparatus and methods for controlling RF switches. In certain configurations, an RF system includes a charge pump for generating a charge pump voltage, an RF switch, a level shifter for turning on or off the RF switch, and a level shifter control circuit for controlling the level shifter. The charge pump receives a mode signal used to enable or disable the charge pump. Additionally, the level shifter receives power in part from the charge pump voltage, and controls the RF switch based on a switch enable signal. The level shifter control circuit receives the mode signal and biases the level shifter with a bias voltage that changes based on a state of the mode signal.

Abstract: Power amplifier having biasing with selectable bandwidth. In some embodiments, a power amplifier can include an amplifying transistor having a base for receiving a signal to be amplified, and a bias circuit configured to bias the amplifying transistor. The bias circuit can include a reference transistor having a base coupled to the base of the amplifying transistor and a collector coupled to a reference current source. The bias circuit can further include a coupling circuit that couples the collector and the base of the reference transistor. The coupling circuit can include a switchable element configured to allow the coupling circuit to be in a first state to provide a first bandwidth for the bias circuit or a second state to provide a second bandwidth for the bias circuit.

Abstract: Disclosed herein are wireless transceivers with switches to reduce harmonic leakage. In some embodiments, a transmitter system includes a power amplification system including a first power amplifier configured to amplify a signal at a first cellular frequency band and a second power amplifier configured to amplify a signal at a second cellular frequency band. The transmitter includes a switch coupled between an output of the second power amplifier and a ground potential. The transmitter includes a controller configured to, based on a band select signal, control the switch and selectively enable or disable each of the first power amplifier and the second power amplifier. Selective control of the switch can reduce harmonic leakage compared to a system that does not include the disclosed switches and controls.

Abstract: Current aggregation using diplexers. A multiplexing system can include a first diplexer and a second diplexer. The first diplexer can have a first transmit terminal, a first receive terminal, and a first common terminal. The first diplexer can be configured to filter a first transmit signal received at the first transmit terminal to a first cellular frequency band and output the filtered first transmit signal at the first common terminal. The first diplexer can be further configured to filter a first receive signal received at the first common terminal to a second cellular frequency band and output the filtered first receive signal at the first receive terminal input. The second diplexer can have a second transmit terminal, a second receive terminal, and a second common terminal. The second diplexer can be configured to filter a second transmit signal received at the second transmit terminal to the second cellular frequency band and output the filtered second transmit signal at the second common terminal.

Abstract: Multimode power amplifier bias circuit with selectable bandwidth. In some embodiments, a bias circuit for a power amplifier can include a first bipolar junction transistor (BJT) configured to pass a reference current. The first BJT can be coupled with a second BJT that performs at least some amplification for the power amplifier. The first and second BJTs can be configured as a current mirror. The bias circuit can further include a coupling circuit that couples the collector and the base of the first BJT. The coupling circuit can include a switchable element to allow the coupling circuit to be in a first state or a second state. The first state can be configured to yield a first bandwidth for the bias circuit, and the second state can be configured to yield a second bandwidth for the bias circuit.

Abstract: Apparatus and methods for controlling radio frequency (RF) switches are disclosed. Provided herein are apparatus and methods for controlling RF switches. In certain configurations, an RF system includes a charge pump for generating a charge pump voltage, an RF switch, a level shifter for turning on or off the RF switch, and a level shifter control circuit for controlling the level shifter. The charge pump receives a mode signal used to enable or disable the charge pump. Additionally, the level shifter receives power in part from the charge pump voltage, and controls the RF switch based on a switch enable signal. The level shifter control circuit receives the mode signal and biases the level shifter with a bias voltage that changes based on a state of the mode signal.

Abstract: Systems, circuits and methods related to low power efficiency improvement in multi-mode multi-band power amplifiers. In some embodiments, a power-amplifier (PA) system can include a first amplification path having one or more PAs configured to generate a high power radio-frequency (RF) signal from an input RF signal when in a high power mode. The PA system can further include a second amplification path having one or more PAs configured to generate a low power RF signal from the input RF signal when in a low power mode. The PA system can further include a switching circuit coupled to the first amplification path and the second amplification path. The switching circuit can be configured to allow amplification of the input RF signal through the first amplification path in the high power mode or the second amplification path in the low power mode.

Abstract: Multimode power amplifier bias circuit with selectable bandwidth. In some embodiments, a bias circuit for a power amplifier can include a first bipolar junction transistor (BJT) configured to pass a reference current. The first BJT can be coupled with a second BJT that performs at least some amplification for the power amplifier. The first and second BJTs can be configured as a current mirror. The bias circuit can further include a coupling circuit that couples the collector and the base of the first BJT. The coupling circuit can include a switchable element to allow the coupling circuit to be in a first state or a second state. The first state can be configured to yield a first bandwidth for the bias circuit, and the second state can be configured to yield a second bandwidth for the bias circuit.

Abstract: According to certain aspects, a circuit board panel includes a first module circuit board and a second module circuit board arranged to define a space that runs between a first portion of the periphery of the first module circuit board and a portion of the periphery of the second module circuit board; and a plurality of shield components each extending across the space and including a first conductive portion mounted along the first portion of the periphery of the first module circuit board, a second conductive portion mounted along the portion of the periphery of the second module circuit board, and a non-conductive portion extending between the first conductive portion and the second conductive portion, the first and second conductive portions of each of the plurality of shield components configured to provide electromagnetic shielding for at least one electronic component mounted on the first and second module circuit boards, respectively.

Abstract: An electronic module with an integrated electromagnetic shield using surface mount shield wall components has been disclosed. Each surface mount shield wall component provides side shielding of the circuitry within the overmolded electronic module and provides an exposed conductive shield wall section to which a top conductive shield can be applied. By including the shield structure as part of the overmolded electronic module, the need for a separate shield and separate process steps for installing the separate shield can be eliminated. Each surface mount shield wall component comprises a non-conductive portion that provides stability during a reflow soldering process, but at least a sacrificial portion of the non-conductive portion can be removed to reduce the amount of area occupied by the overmoldable shield structure.