A display apparatus and a method for processing audio are provided, the display apparatus includes a circuit board provided with a hybrid circuit, a filter circuit and a speaker; the hybrid circuit is configured to receive an original audio signal and superpose a first sub-signal of the original audio signal on a second sub-signal of the original audio signal to obtain a hybrid audio signal; the first sub-signal includes at least one channel of audio signal, the second sub-signal includes at least two channels of audio signal; the filter circuit is configured to filter the hybrid audio signal according to a frequency characteristic of the first sub-signal and the second sub-signal to obtain a restored original audio signal; and the speaker, connected with the filter circuit, is configured to output the restored original audio signal.

A power amplifier includes a transistor, a temperature sensor and a filter. The transistor is used to receive a bias signal and amplify a radio frequency (RF) signal. The temperature sensor is arranged in proximity to the transistor, and is used to detect a temperature of the transistor to provide a voltage signal at a control node accordingly. The filter is coupled to the temperature sensor and is used to filter the voltage signal to generate a filtered voltage. The bias signal is adjusted according to the filtered voltage.

A power amplifier includes a transistor, a temperature sensor and a filter. The transistor is used to receive a bias signal and amplify a radio frequency (RF) signal. The temperature sensor is arranged in proximity to the transistor, and is used to detect a temperature of the transistor to provide a voltage signal at a control node accordingly. The filter is coupled to the temperature sensor and is used to filter the voltage signal to generate a filtered voltage. The bias signal is adjusted according to the filtered voltage.

Aspects of this disclosure relate to methods of manufacturing bulk acoustic wave components. Such methods include plasma dicing to singulate individual bulk acoustic wave components. A buffer layer can be formed over a substrate of bulk acoustic wave components such that streets are exposed. The bulk acoustic wave components can be plasma diced along the exposed streets to thereby singulate the bulk acoustic wave components

An envelope tracking (ET) power amplifier apparatus is provided. The ET power amplifier apparatus includes an amplifier circuit configured to amplify a radio frequency (RF) signal based on an ET voltage and a tracker circuit configured to generate the ET voltage based on an ET target voltage. The ET power amplifier apparatus also includes a control circuit. The control circuit is configured to dynamically determine a voltage standing wave ratio (VSWR) change at a voltage output relative to a nominal VSWR and cause an adjustment to the ET voltage. By dynamically determining the VSWR change and adjusting the ET voltage in response to the VSWR change, the amplifier circuit can operate under a required EVM threshold across all phase angles of the RF signal.

An envelope tracking (ET) power amplifier apparatus is provided. The ET power amplifier apparatus includes an amplifier circuit configured to amplify a radio frequency (RF) signal based on an ET voltage and a tracker circuit configured to generate the ET voltage based on an ET target voltage. The ET power amplifier apparatus also includes a control circuit. The control circuit is configured to dynamically determine a voltage standing wave ratio (VSWR) change at a voltage output relative to a nominal VSWR and cause an adjustment to the ET voltage. By dynamically determining the VSWR change and adjusting the ET voltage in response to the VSWR change, the amplifier circuit can operate under a required EVM threshold across all phase angles of the RF signal.

A system includes a radio frequency (RF) connector terminal that is configured to connect to an antenna, and a RF transmitter that transmits RF power to the RF connector terminal. The system further includes a power measurement unit that measures, as a first power measurement, first RF power of the RF transmitter power that is reflected via the RF connector terminal, and a controller that causes a transmission path discontinuity between the RF transmitter and the RF connector terminal. The power measurement unit further measures, as a second power measurement, second RF power of the RF transmitter power that is reflected from the discontinuity. The controller further determines if a first antenna is connected to the RF connector terminal based on the first and second power measurements.

A system includes a radio frequency (RF) connector terminal that is configured to connect to an antenna, and a RF transmitter that transmits RF power to the RF connector terminal. The system further includes a power measurement unit that measures, as a first power measurement, first RF power of the RF transmitter power that is reflected via the RF connector terminal, and a controller that causes a transmission path discontinuity between the RF transmitter and the RF connector terminal. The power measurement unit further measures, as a second power measurement, second RF power of the RF transmitter power that is reflected from the discontinuity. The controller further determines if a first antenna is connected to the RF connector terminal based on the first and second power measurements.

Two transistor rows are arranged on or in a substrate. Each of the two transistor rows is configured by a plurality of transistors aligned in a first direction, and the two transistor rows are arranged at an interval in a second direction orthogonal to the first direction. A first wiring is arranged between the two transistor rows when seen from above. The first wiring is connected to collectors or drains of the plurality of transistors in the two transistor rows. The first bump overlaps with the first wiring when seen from above, is arranged between the two transistor rows, and is connected to the first wiring.

A radio-frequency module including a module substrate having a first main surface and a second main surface on opposite sides; a low-noise amplifier disposed on the second main surface; and a power amplifier circuit in a Doherty configuration. The power amplifier including a first phase circuit; a second phase circuit; a carrier amplifier disposed on the first main surface and including an input terminal connected to a first end of the first phase circuit and an output terminal connected to a first end of the second phase circuit; and a peaking amplifier disposed on the first main surface and including an input terminal connected to a second end of the first phase circuit and an output terminal connected to a second end of the second phase circuit.