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

A power amplifier module includes a first substrate and a second substrate, at least part of the second substrate being disposed in a region overlapping the first substrate. The second substrate includes a first amplifier circuit and a second amplifier circuit. The first substrate includes a first transformer including a primary winding having a first end and a second end and a secondary winding having a first end and a second end; a second transformer including a primary winding having a first end and a second end and a secondary winding having a first end and a second end; and multiple first conductors disposed in a row between the first transformer and the second transformer, each of the multiple first conductors extending from the wiring layer on a first main surface to the wiring layer on a second main surface of the substrate.

A semiconductor device includes a semiconductor chip that has a main surface, a device region that is demarcated at the main surface, a differential amplifier that is formed in the device region and that amplifies and outputs a differential signal input to the differential amplifier, an insulation layer that covers the device region on the main surface, and a shield electrode that is incorporated in the insulation layer such as to conceal the device region in a plan view and that is fixed to a ground potential.

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.

An output matching circuit includes a transformer having one end electrically connected to an output terminal of a power amplifier element that amplifies an input signal and another end electrically connected to a terminal connected to a load, and converting an impedance of the terminal connected to the load to an impedance higher than an impedance of the output terminal, a first filter circuit that attenuates a signal within a first frequency band higher than a transmission frequency band of the input signal, and a second filter circuit that attenuates a signal within a second frequency band higher than the first frequency band.

A high-frequency amplifier for an active EMI filter with a symmetric class B emitter-follower output stage driven by a driver stage, with a sense output resistor. Both terminals of the sense resistor are brought to the noninverting, respecting inverting input of the driver stage through two dividers of the same ratio, in a global voltage feedback loop. The amplifier is configured to provide a high output impedance at 10 kHz and up to 100 MHz, a peak-to-peak output current of 2-10 ampere and a low quiescent current of less than 400 mA. The invention includes EMI filters with such a high-frequency current source, for example in the current-sense current-inject feedback configuration.

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 method for ramping a switched capacitor power amplifier is disclosed, where the switched capacitor power amplifier comprises a plurality of capacitors in a capacitor bank, and where a number of the capacitors in the capacitor bank are activated. The method comprises changing the number of capacitors in the capacitor bank that are activated, maintaining the changed number of activated capacitors in the capacitor bank for a period of time, and repeating the changing and maintaining, where a length of the period of time is varied between at least two repetitions of the maintaining.

An audio signal modulation and amplification circuit includes a common-mode electric potential controller, a carrier generator, and channel circuits. The common-mode electric potential controller is configured to generate one or more first common-mode electric potentials and second common-mode electric potentials. The carrier generator is adapted to receive the first common-mode electric potential to generate a carrier signal. Each of the channel circuits includes a filter, a comparison circuit, and a driving circuit. The filter is adapted to filter an input signal and generate a filtered signal based on a corresponding one of the second common-mode electric potentials. The comparison circuit is configured to compare the potential of the carrier signal with the potential of the filtered signal to generate a pulse-width modulation signal. The driving circuit is configured to be turned on or off in response to the pulse-width modulation signal to output a load driving signal.

A power amplifier module includes a first substrate and a second substrate, at least part of the second substrate being disposed in a region overlapping the first substrate. The second substrate includes a first amplifier circuit and a second amplifier circuit. The first substrate includes a first transformer including a primary winding having a first end and a second end and a secondary winding having a first end and a second end; a second transformer including a primary winding having a first end and a second end and a secondary winding having a first end and a second end; and multiple first conductors disposed in a row between the first transformer and the second transformer, each of the multiple first conductors extending from the wiring layer on a first main surface to the wiring layer on a second main surface of the substrate.