Abstract: Power amplifier circuitry includes a power amplifier including an input node and an output node, biasing circuitry, a selectable impedance network, and an input capacitor. The input capacitor is coupled to the input node of the power amplifier. The biasing circuitry is coupled to the input node of the power amplifier through the selectable impedance network. The power amplifier is operable in a low power operating mode and a high power operating mode. In the low power operating mode, the biasing circuitry delivers a first biasing current to the input node of the power amplifier, and a first impedance level of the selectable impedance is selected. In the high power operating mode, the biasing circuitry delivers a second biasing current to the input node of the power amplifier, and a second impedance level of the selectable impedance is selected.

Abstract: This disclosure relates generally to radio frequency (RF) amplification devices and methods of limiting an RF signal current. Embodiments of the RF amplification device include an RF amplification circuit and a feedback circuit. The RF amplification circuit is configured to amplify an RF input signal so as to generate an amplified RF signal that provides an RF signal current with a current magnitude. The feedback circuit is used to limit the RF signal current. In particular, a thermal sense element in the feedback circuit is configured to generate a sense current, and thermal conduction from the RF amplification circuit sets a sense current level of the sense current as being indicative of the current magnitude of the RF signal current. To limit the RF signal current, the feedback circuit decreases the current magnitude of the RF signal current in response to the sense current level reaching a trigger current level.

Abstract: Power amplifier circuitry includes a power amplifier including an input node and an output node, biasing circuitry, a selectable impedance network, and an input capacitor. The input capacitor is coupled to the input node of the power amplifier. The biasing circuitry is coupled to the input node of the power amplifier through the selectable impedance network. The power amplifier is operable in a low power operating mode and a high power operating mode. In the low power operating mode, the biasing circuitry delivers a first biasing current to the input node of the power amplifier, and a first impedance level of the selectable impedance is selected. In the high power operating mode, the biasing circuitry delivers a second biasing current to the input node of the power amplifier, and a second impedance level of the selectable impedance is selected.

Abstract: The present disclosure relates to multi-mode RF power amplifier (PA) circuitry that may include a first PA path and a second PA path, each of which is fed from a common RF input. During a first operating mode, the first PA path receives and amplifies a first RF input signal via the common RF input, and during a second operating mode, the second PA path receives and amplifies a second RF input signal via the common RF input. To facilitate sharing of the common RF input, during the first operating mode, the second PA path is substantially de-coupled from the common RF input, and during the second operating mode, the first PA path is substantially de-coupled from the common RF input. By sharing the common RF input, size and costs of the multi-mode RF PA circuitry may be reduced.

Abstract: This disclosure relates generally to radio frequency (RF) amplification devices and methods of limiting an RF signal current. Embodiments of the RF amplification device include an RF amplification circuit and a feedback circuit. The RF amplification circuit is configured to amplify an RF input signal so as to generate an amplified RF signal that provides an RF signal current with a current magnitude. The feedback circuit is used to limit the RF signal current. In particular, a thermal sense element in the feedback circuit is configured to generate a sense current, and thermal conduction from the RF amplification circuit sets a sense current level of the sense current as being indicative of the current magnitude of the RF signal current. To limit the RF signal current, the feedback circuit decreases the current magnitude of the RF signal current in response to the sense current level reaching a trigger current level.

Abstract: The present invention is a low series impedance directional power detector, which may be used to measure either forward or reverse power in a radio frequency (RF) circuit. The directional power detector includes current detection circuitry to directionally measure current, voltage detection circuitry to measure voltage, and combining circuitry to combine the directional RF current measurements and the RF voltage measurements into a combined RF measurement, which is indicative of directional power. The current detection circuitry and voltage detection circuitry apply any phase-shifts that are needed to detect power in the direction of interest and ignore power in the opposite direction when the directional power detector is presented with a complex load.

Abstract: The present invention provides a quadrature RF amplifier output network that includes a quadrature RF combiner and impedance transformation circuitry. The output network is coupled between a quadrature RF amplifier and an antenna, or other downstream circuitry to optimize net RF power transfer and improve overall power efficiency. The quadrature RF combiner phase-shifts and combines quadrature RF signals from the quadrature RF amplifier into a single combined RF signal that feeds the impedance transformation circuitry. The impedance transformation circuitry transforms an impedance that is presented to the output of the quadrature RF amplifier output network into a desired quadrature impedance that is presented to the outputs of the quadrature RF amplifier. Termination circuitry is coupled to the quadrature RF combiner to capture improperly phased signals, reflected signals, or imbalanced signals.

Abstract: A system for detecting both forward and reverse power of a power amplifier in the presence of harmonics created by the power amplifier is provided. A forward power detection system receives detection signals from an in-phase amplifier leg and a quadrature-phase amplifier leg of the power amplifier. The forward power detection system applies a phase shift to the detection signals such that forward components of the detection signals are essentially in-phase, and reverse components of the detection signals are essentially 180 degrees out-of-phase. The phase shifted detection signals are then combined and filtered to provide a signal indicative of forward power. In a similar fashion, a reverse power detection system applies a phase shift to the detection signals to provide a signal indicative of reverse power.