A Doherty amplifier is configured in such a way that a phase adjustment circuit adjusts either the phase of a return signal going to a first auxiliary amplification element as a result of passage of a first signal amplified by a second main amplification element through a second auxiliary amplification element as the return signal, or the phase of the return signal going to the second auxiliary amplification element as a result of reflection of the return signal by the first auxiliary amplification element, at a time of a backoff operation of the second auxiliary amplification element, in such a way that the sum of the phase of the return signal going to the first auxiliary amplification element and the phase of the return signal going to the second auxiliary amplification element is not equal to 0 degrees in the operating frequency band of the first signal.

A Doherty amplifier is configured in such a way that a phase adjustment circuit adjusts either the phase of a return signal going to a first auxiliary amplification element as a result of passage of a first signal amplified by a second main amplification element through a second auxiliary amplification element as the return signal, or the phase of the return signal going to the second auxiliary amplification element as a result of reflection of the return signal by the first auxiliary amplification element, at a time of a backoff operation of the second auxiliary amplification element, in such a way that the sum of the phase of the return signal going to the first auxiliary amplification element and the phase of the return signal going to the second auxiliary amplification element is not equal to 0 degrees in the operating frequency band of the first signal.

A package or a chip including a linear amplifier and a power amplifier is provided, wherein the linear amplifier is configured to receive an envelope tracking signal to generate an amplified envelope tracking signal, the power amplifier is supplied by an envelope tracking supply voltage comprising a DC supply voltage and the amplified envelope tracking signal, and the power amplifier is configured to receive an input signal to generate an output signal.

A package or a chip including a linear amplifier and a power amplifier is provided, wherein the linear amplifier is configured to receive an envelope tracking signal to generate an amplified envelope tracking signal, the power amplifier is supplied by an envelope tracking supply voltage comprising a DC supply voltage and the amplified envelope tracking signal, and the power amplifier is configured to receive an input signal to generate an output signal.

An apparatus is disclosed for bidirectional amplification with phase-shifting. In example implementations, an apparatus includes a phase shifter with a bidirectional amplifier. The bidirectional amplifier includes a first transistor coupled between a first plus node and a second minus node, a second transistor coupled between a first minus node and a second plus node, a third transistor coupled between the first plus node and the second minus node, and a fourth transistor coupled between the first minus node and the second plus node. The bidirectional amplifier also includes a fifth transistor coupled between the first plus node and the second plus node, a sixth transistor coupled between the first minus node and the second minus node, a seventh transistor coupled between the first plus node and the second plus node, and an eighth transistor coupled between the first minus node and the second minus node.

An apparatus is disclosed for bidirectional amplification with phase-shifting. In example implementations, an apparatus includes a phase shifter with a bidirectional amplifier. The bidirectional amplifier includes a first transistor coupled between a first plus node and a second minus node, a second transistor coupled between a first minus node and a second plus node, a third transistor coupled between the first plus node and the second minus node, and a fourth transistor coupled between the first minus node and the second plus node. The bidirectional amplifier also includes a fifth transistor coupled between the first plus node and the second plus node, a sixth transistor coupled between the first minus node and the second minus node, a seventh transistor coupled between the first plus node and the second plus node, and an eighth transistor coupled between the first minus node and the second minus node.

An electronic device may include wireless circuitry with a baseband processor, a transceiver circuit, a front-end module, and an antenna. The front-end module may include amplifier circuitry such as a low noise amplifier for amplifying received radio-frequency signals. The amplifier circuitry is operable in a non-carrier-aggregation mode and a carrier aggregation mode. The amplifier circuitry may include an input transformer that is coupled to multiple amplifier stages such as a common gate amplifier stage, a cascode amplifier stage, and a common source amplifier stage. The common gate amplifier stage may include switches for selectively activating a set of cross-coupled capacitors to help maintain input impedance matching in the non-carrier-aggregation mode and the carrier-aggregation mode. The common source amplifier stage may include additional switches for activating and deactivating the common source amplifier stage to help maintain the gain in the non-carrier-aggregation mode and the carrier-aggregation mode.

An electronic device may include wireless circuitry with a baseband processor, a transceiver circuit, a front-end module, and an antenna. The front-end module may include amplifier circuitry such as a low noise amplifier for amplifying received radio-frequency signals. The amplifier circuitry is operable in a non-carrier-aggregation mode and a carrier aggregation mode. The amplifier circuitry may include an input transformer that is coupled to multiple amplifier stages such as a common gate amplifier stage, a cascode amplifier stage, and a common source amplifier stage. The common gate amplifier stage may include switches for selectively activating a set of cross-coupled capacitors to help maintain input impedance matching in the non-carrier-aggregation mode and the carrier-aggregation mode. The common source amplifier stage may include additional switches for activating and deactivating the common source amplifier stage to help maintain the gain in the non-carrier-aggregation mode and the carrier-aggregation mode.

An array substrate has a display area and a bonding region. The display area includes a distal region, a proximal region, and a middle region therebetween. The array substrate includes a base, a common electrode located in the display area, a connecting lead disposed outside the distal region, a conductive frame at least partially surrounding the display area, and at least one first common signal line, at least one second common signal line and at least one third common signal line. The first common signal line, the second common signal line and the third common signal line are respectively coupled to portions of the common electrode located in the distal region, the proximal region and the middle region. The first common signal line is coupled to the connecting lead. The connecting lead and the portion of the common electrode located in the distal region are coupled to the conductive frame.

A modular headphone system that can afford the wearer configurable choices of hearing protection and quality sound delivery for music and programming is provided. In an embodiment, a modular headphone includes a headband and an earpiece mounted to the headband. The earpiece comprises a can comprising a speaker, the can secured to the headband. A removable and replaceable music ear cup is removably mountable to the can to overlie the speaker. A removable and replaceable hearing protection/sound amplification (HP/amp) ear cup is removably mountable to the can to overlie the speaker.