Abstract: A cascode amplifier comprises: a common-source amplifier includes a first MOST (metal-oxide semiconductor transistor) of a first type configured to receive a first input signal and output a first current to a first node in accordance with a body voltage applied at a body of the first MOST of the first type; a first common-gate amplifier comprising a second MOST of the first type and configured to receive the first current from the first node and output a second current to a second drain node in accordance with a first gate voltage; a dynamic body voltage generator configured to receive the first input signal and output the body voltage; and a load configured to establish a third voltage at a third drain node in response to the second current through a DC (direct current) path between the second drain node and the third drain node.

Abstract: A power amplifier includes a voltage converter that converts an input voltage to a converted voltage; an output circuit coupled to receive the converted voltage and configured to generate an output voltage at an output node; a discharge transistor electrically connected between the output node and earth and configured to perform discharge at the output node under control of a control voltage; a voltage tracking circuit that tracks the input voltage; and an electric charge storage circuit being under control of the voltage tracking circuit and configured to maintain the control voltage when the input voltage drops to a predetermined voltage level in order to continuously turn on the discharge transistor before completing discharge at the output node.

Abstract: Power amplifier systems with a switchable transistor array and a switchable biasing circuit are provided herein. In certain embodiments, a power amplifier system includes a power amplifier that amplifies an RF signal, and a biasing circuit that controls a bias of the power amplifier. The power amplifier includes a transistor array in which a number of active transistors that amplify the RF signal changes based on a selected power mode of the power amplifier system. Additionally, the biasing circuit changes the bias of power amplifier based on the selected power mode. For instance, the biasing circuit can change an amount of bias current and/or a bias voltage level of the power amplifier based on the selected power mode, for instance, a low power mode or a high power mode.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for a programmable input impedance circuit for a radio frequency (RF) low noise amplifier (LNA) including a high impedance mode circuit and a low impedance mode circuit. The high impedance mode circuit includes an inductor-degenerated transconductor transistor, an inductor selectively coupled between a source of the inductor-degenerated transconductor transistor and a ground, and a capacitor coupled between a gate of the inductor-degenerated transconductor transistor and the source of the inductor-degenerated transconductor transistor. The low impedance mode circuit includes a shunt resistor selectively coupled between an RF input source and an alternating current (AC) ground.

Abstract: An example apparatus includes: an amplifier having an input and an output; feedback circuitry having a first terminal and a second terminal, the first terminal of the feedback circuitry directly connected to the input of the amplifier, the second terminal of the feedback circuitry directly connected to the output of the amplifier; voltage divider circuitry having a first terminal and a second terminal, the first terminal of the voltage divider circuitry directly connected to the output of the amplifier; and a capacitor having a terminal directly connected to the second terminal of the voltage divider circuitry.

Abstract: The present application discloses a radio frequency (RF) device. The radio frequency device includes a power amplifier, a power detector, and a digital signal processor (DSP). The power amplifier outputs a RF signal. The power detector receives the RF signal, and performs a plurality of calibration operations to generate a plurality of calibration voltages corresponding to a plurality of bias voltage, wherein the calibration operations are performed at the bias voltages respectively, and the calibration voltages are temperature-correlated due to that electrical characteristics of the power detector are temperature-correlated. The DSP controls the power detector to operate at the bias voltages, obtains an index voltage for indicating power of the RF signal by performing calculations upon the calibration voltages to reduce temperature dependency of the index voltage, and adjusts a gain of the power amplifier according to the index voltage.

Abstract: A power amplifier includes a current generating circuit, a first mirroring circuit, a power amplifying circuit and a stacked circuit, in which the current generating circuit is configured to output a first current according to a received first control voltage; the first mirroring circuit is configured to, according to the first current, minor the current and output a first bias current, the first bias current for being input into the power amplifying circuit; and the power amplifying circuit is configured to, according to a first radio frequency signal and the first bias current, output a second radio frequency signal with a power that meets a preset condition.

Abstract: Apparatus and methods for power detection in radio frequency (RF) systems are disclosed. In certain embodiments, a power detection system includes a power amplifier, a directional coupler connected to an output of the power amplifier, and a power detector that generates a differential power detection signal based on a single-ended radio frequency input signal received from the directional coupler. The differential power detection signal indicates an output power of the power amplifier, for example, a root mean square (RMS) output power.

Abstract: Provided is a low noise amplification circuit, comprising: a RF amplification circuit, one end of which is connected with a signal input end, another end is connected with the output impedance matching circuit; an output impedance matching circuit, one end of which is connected with the RF amplification circuit, another end is connected with the attenuation network; an attenuation network, one end of which is connected with the output impedance matching circuit, another end is connected with a signal output end; a passive attenuation path, one end of which is connected with the signal input end, another end is connected with a connection node between the matching circuit and the network; and an impedance regulation network, configured to, in a first working mode, resonate with a parasitic capacitance generated by the network, in a second working mode, resonate with a parasitic capacitance generated by the network and the attenuation path.

Abstract: The disclosure is towards parametric amplifiers with inductive input coupling for quantum computing systems. One example aspect of the present disclosure is directed to a quantum computing system comprising a first qubit, a first measurement device, and a first amplifier. The first measurement device is configured to generate a first qubit signal corresponding to a first quantum state of the first qubit. The first amplifier is configured to amplify the first qubit signal. The first amplifier comprises a first transmission-line resonator. The first transmission-line resonator provides an inductive reactance for an electrical coupling between the first measurement device and the first amplifier. The inductive reactance for the electrical coupling enables a transmission of the first qubit signal.

Abstract: A Doherty amplifier is provided with a lumped-element combiner that includes a first capacitor and an inductor. Should the inductor be coupled between an output terminal of the main amplifier and an output node of the Doherty amplifier, the first capacitor couples between an output terminal of the auxiliary amplifier and the output node. Conversely, if the first capacitor is coupled between the output terminal of the main amplifier and the output node, then the inductor couples between the output terminal of the auxiliary amplifier and the output node. A current scaling ratio of the Doherty amplifier ranges from 0.4 to 0.6 to enhance the bandwidth.

Abstract: A power amplifier includes an amplifier circuit configured to amplify a radio frequency input signal, a bias circuit configured to output a bias current to the amplifier circuit, and a bias suppression circuit configured to suppress the bias current based on the radio frequency input signal. The bias circuit includes a first transistor including a collector and a base that are electrically connected to a first node to be input with a current and an emitter electrically connected to a second node, a second transistor including a collector and a base that are electrically connected to the second node, and a third transistor including a base electrically connected to the first node and an emitter, the third transistor being configured to output a bias current from the emitter. The bias suppression circuit draws a current from the second node of the bias circuit based on the radio frequency input signal.

Abstract: A receiver circuit includes: a constant current circuit to generate second paired current signals according to first paired current signals; a current splitter circuit to output third paired current signals generated from the second paired current signals, from a first output node and a second output node; and a differential TIA circuit to output paired voltage signals from a first output terminal and a second output terminal, according to the third paired current signals input from a third input node and a fourth input node. The differential TIA circuit includes a first feedback resistor element connected between the third input node and the second output terminal, and a second feedback resistor element connected between the fourth input node and the first output terminal. Average voltages of the first and second output nodes and the first and second output terminals are set to be equivalent to each other.

Abstract: An apparatus includes a first circuit that has a photodetector. The photodetector is reverse-biased by a reverse-bias voltage. A common mode voltage is added to the reverse-bias voltage to provide an offset to the photodetector voltage. A second circuit is coupled to the first circuit to provide the common mode voltage for the first circuit. A third circuit is coupled to the second circuit that includes a first voltage source and a second voltage source having opposite voltages equal to half of the reverse-bias voltage. Each one of the first voltage source and the second voltage source are coupled between separate input and output nodes of input and output ports of the third circuit. The first voltage source and the second voltage source provide the reverse-bias voltage to the first circuit to reverse-bias the photodetector. The third circuit provides a photodetector current at an output of the third circuit.

Abstract: A Doherty power amplifier that includes an input, an output, a main power amplification device connected between the input and the output; and an auxiliary power amplification device connected between the input and the output. The auxiliary power amplification device is arranged in parallel with the main power amplification device. The Doherty power amplifier further includes a first dual-mode impedance transformer connected between the main power amplification device and the output, and a second dual-mode impedance transformer between the auxiliary power amplification device and the output. The first and second dual-mode ITs each is adapted to convert an input impedance of a corresponding one of the main and auxiliary power amplification devices to a load impedance at the output, at two frequencies simultaneously.

Abstract: Power amplifiers including balanced coaxial baluns are described. One example includes first and second amplifiers coupled to a balanced pair of first and second microstrip lines on a circuit board. A balun is coupled between the microstrip lines at a balanced end and between a conductive trace and a ground plane of the circuit board at an unbalanced end of the balun. The balun includes a coaxial balun line and a surface mount balancing inductor. The coaxial line includes center and shield conductors. A first end of the center conductor is coupled to the first microstrip line and a first end of the shield conductor is coupled to the second microstrip line at the balanced end of the balun. The balancing inductor is coupled between the first microstrip line and the ground plane to maintain symmetry for the balanced pair of microstrip lines.

Abstract: An electronic device including a Doherty power amplifier is provided. The electronic device includes a carrier amplifier, a first circuit coupled to an output terminal of the carrier amplifier, a peaking amplifier, a second circuit coupled to an output terminal of the peaking amplifier, and a network circuit. The network circuit includes the Doherty power amplifier and a transmission line for impedance matching with a resonance circuit. The resonance circuit may be disposed between a first area and a second area of the transmission line. The Doherty power amplifier provides an output impedance in a first range distributed based on a frequency within a bandwidth. The network circuit provides a load impedance in a second range distributed based on the frequency within the bandwidth. The first area of the transmission line provides a first phase shift impedance. The second area of the transmission line provides a second phase shift impedance.

Abstract: A Doherty amplifier includes: a first filter circuit to output a first input signal obtained by attenuating an input signal lying in a first frequency band, and to output a second input signal obtained by allowing passage of an input signal lying in a second frequency band; a second filter circuit to output a third input signal obtained by attenuating an input signal lying in the first frequency band, and to output a fourth input signal obtained by attenuating an input signal lying in the second frequency band; a first amplifier to operate as an auxiliary amplifier when receiving the first input signal, and to operate as a main amplifier when receiving the second input signal; and a second amplifier tip operate as the main amplifier when receiving the third input signal, and to operate as the auxiliary amplifier when receiving the fourth input signal.

Abstract: Systems and methods for analog predistortion (APD) in power amplifiers are disclosed. In one aspect, APD may be provided in a front-end module (FEM) of a transmitter. More specifically, the APD may include different predistortions based on where within a frequency band the signal to be distorted is operating (i.e., sub-band APD). The APD in the FEM may further be based on operating conditions such as temperature within the FEM. Still further, the FEM may be configured to apply different APD based on whether or not a baseband processor (BBP) applies digital predistortion (DPD). At a minimum, the provision of the APD may make the operation of a power amplifier in FEM more linear. Further, where DPD is present, the use of the APD may simplify the requirements for the DPD provided in the BBP.

Abstract: A power supply modulation device includes a unit detecting, from a first digital signal, a first amplitude being the amplitude of a first analog signal provided to a first amplifier and detecting, from a second digital signal, a second amplitude being the amplitude of a second analog signal provided to a second amplifier; a unit that calculates a time differential value of a ratio of the first amplitude to a sum of the first amplitude and the second amplitude, and determines, on the basis of the time differential value, whether or not output impedance of a combining circuit that combines together the first analog signal amplified and the second analog signal changes along with a change in power of the combined signal; and a unit that controls a power supply voltage supplied to each of the first amplifier and the second amplifier, on the basis of the determination.