An active filter reduces Electro-Magnetic Interference (EMI) created by current flowing through a power line. The active filter connects to the power line at a single node through a connection capacitor. A sense current flows through the connection capacitor when the power line current changes. This sense current is applied to a non-inverting input of an op amp to drive a power amplifier circuit through a filter capacitor. The power amplifier circuit increases the current drive of the op amp to charge a transfer capacitor that converts the power amplifier output current to a transfer voltage. The transfer capacitor is connected to the connection capacitor so that the transfer voltage is injected back into the power line through the connection capacitor as an injected voltage that compensates for the sensed current. Op amp gain is adjustable by variable resistors that connect to the inverting input of the op amp.

In a radio frequency power amplifier with harmonic suppression, one end of an input matching circuit is connected with a radio frequency input end; and another end is connected with a base of a power amplification transistor having a collector connected with a power supply voltage through a first matching branch, and an emitter connected with a first connection point on a package substrate. The collector of the power amplification transistor is connected with a radio frequency output end through a second matching branch that is connected with the package substrate. A harmonic control circuit has a first end connected with the collector of the power amplification transistor, and a second end connected with a second connection point on the package substrate.

A thermal and environmental noise suppressing interface circuit which is configured to operate cold and is configured to perform biasing with suppression of noise currents from room temperature noise voltages and dc coupled rf readout of a superconducting device under test with a single coaxial cable or equivalent conductor pair. The circuit is configured to suppress the propagation of thermal and environmental noises to/from sensors operating at a different temperature from its operating and control equipment while maintaining a single input-output channel, and provides for the placement of a local grounding impedance on an intercept board.

A Doherty amplifier module includes a substrate, an RF signal splitter, a carrier amplifier die, and first and second peaking amplifier dies. The RF signal splitter divides an input RF signal into first, second, and third input RF signals, and conveys the input RF signals to splitter output terminals. The carrier amplifier die includes one or more first power transistors configured to amplify, along a carrier signal path, the first input RF signal to produce an amplified first RF signal. The peaking amplifier dies each include one or more additional power transistors configured to amplify, along first and second peaking signal paths, the second and third input RF signals to produce amplified second and third RF signals. The dies are coupled to the substrate so that the RF signal paths through the carrier and one or more of the peaking amplifier dies extend in substantially different (e.g., orthogonal) directions.

Variations in a receiving circuit employing differential signaling are reduced. The receiving circuit converts a first signal and a second signal which are supplied through differential signaling into a third signal which is a single-ended signal and outputs the third signal. The receiving circuit includes an operational amplifier, a first element, a first transistor, and a first circuit. The first element is connected to the first circuit through a first node to which the first transistor is connected. The first signal and the second signal that is the inverse of the first signal are supplied to the operational amplifier. The operational amplifier supplies an output signal to the first element, and a first preset potential is supplied to the first node through the first transistor. A signal including variations of the operational amplifier is stored in the first element in accordance with the first preset potential. The first circuit that is supplied with the first preset potential determines an initial value of the third signal without being influenced by the signal including variations of the operational amplifier.

A circuit module (100) includes an electronic component (30), a plurality of conductor posts (40), a mold layer (50) that seals a plurality of the electronic components (30) and the plurality of conductor posts (40), and a shield layer (60) on the mold layer (50). The electronic components (30) include a first electronic component (31) and second electronic components (32, 36). The plurality of conductor posts (40) includes a group of conductor posts (400) traversing between the first electronic component (31) and the second electronic components (32, 36). The shield layer (60) includes a slit (600) that, with respect to each conductor post (40) included in the group (400) of conductor posts, in a plan view, passes and extends between the conductor post (40) and the first electronic component (31), or between the conductor post (40) and the second electronic components (32, 36).

Embodiments of the disclosure relate to optimizing power efficiency of a power amplifier circuit to reduce power consumption in a remote unit in a wireless distribution system (WDS). A power amplifier circuit is provided in the remote unit to amplify a received input signal associated with a signal channel(s) to generate an output signal at an aggregated peak power. In this regard, a control circuit is configured to analyze at least one physical property related to the signal channel(s) to determine a maximum output power of the power amplifier circuit. Accordingly, the control circuit configures the power amplifier circuit according to the determined maximum output power. By configuring the maximum output power based on the signal channel(s) in the input signal, it may be possible to optimize the power efficiency of the power amplifier circuit, thus helping to reduce the power consumption of the remote unit.

A thermal and environmental noise suppressing interface circuit which is configured to operate cold and is configured to perform biasing with suppression of noise currents from room temperature noise voltages and dc coupled rf readout of a superconducting device under test with a single coaxial cable or equivalent conductor pair. The circuit is configured to suppress the propagation of thermal and environmental noises to/from sensors operating at a different temperature from its operating and control equipment while maintaining a single input-output channel, and provides for the placement of a local grounding impedance on an intercept board.

Embodiments of Doherty Power Amplifier (PA) and other PA packages are provided, as are systems including PA packages. In embodiments, the PA package includes a package body having a longitudinal axis, a first group of input-side leads projecting from a first side of the package body and having an intra-group lead spacing, and a first group of output-side leads projecting from a second side of the package body and also having the intra-group lead spacing. A first carrier input lead projects from the first package body side and is spaced from the first group of input-side leads by an input-side isolation gap, which has a width exceeding the intra-group lead spacing. Similarly, a first carrier output lead projects from the second package body side, is laterally aligned with the first carrier input lead, and is separated from the first group of output-side leads by an output-side isolation gap.

A Doherty amplifier module includes a substrate, an RF signal splitter, a carrier amplifier die, and first and second peaking amplifier dies. The RF signal splitter divides an input RF signal into first, second, and third input RF signals, and conveys the input RF signals to splitter output terminals. The carrier amplifier die includes one or more first power transistors configured to amplify, along a carrier signal path, the first input RF signal to produce an amplified first RF signal. The peaking amplifier dies each include one or more additional power transistors configured to amplify, along first and second peaking signal paths, the second and third input RF signals to produce amplified second and third RF signals. The dies are coupled to the substrate so that the RF signal paths through the carrier and one or more of the peaking amplifier dies extend in substantially different (e.g., orthogonal) directions.