Methods and systems are provided for controlling rail-voltages for amplifier output stages. In some examples, a method may include receiving sets of data values (e.g., at a power-supply control circuitry) for control of a rail voltage of an amplifier output stage. The method may also include determining that the receipt of a pending set of data values has been interrupted. Then, upon the determination that the receipt of the pending plurality of data values has been interrupted, the method may include decreasing the rail voltage to a non-boosted rail-voltage level.

A gaming unit and producing a game-audio output of a varying volume level and a chat-voice output is connected to headphones adapted to be worn by a player of the unit and connected to the gaming unit for making the chat-voice output and the game-audio output audible to the player. A circuit or software associated with the headphones can increase the chat-voice volume level generally proportionately to the game-audio volume level.

An apparatus is disclosed for bidirectional variable gain amplification. In an example aspect, an apparatus comprises an antenna element of an antenna array and a wireless transceiver. The wireless transceiver comprises a transmit path coupled to the antenna element, a receive path coupled to the antenna element, and a phase shifter disposed in both the transmit path and the receive path. The phase shifter is configured to operate in an active mode and comprises a first bidirectional variable gain amplifier and a second bidirectional variable gain amplifier.

A method, an apparatus, and logic to post-process raw gains determined by input processing to generate post-processed gains, comprising using one or both of delta gain smoothing and decision-directed gain smoothing. The delta gain smoothing comprises applying a smoothing filter to the raw gain with a smoothing factor that depends on the gain delta: the absolute value of the difference between the raw gain for the current frame and the post-processed gain for a previous frame. The decision-directed gain smoothing comprises converting the raw gain to a signal-to-noise ratio, applying a smoothing filter with a smoothing factor to the signal-to-noise ratio to calculate a smoothed signal-to-noise ratio, and converting the smoothed signal-to-noise ratio to determine the second smoothed gain, with smoothing factor possibly dependent on the gain delta.

A semiconductor device is provided, the device including a first detection section having a removal section to remove DC offset components included in each of an input signal and an output signal output from an amplification section that amplifies the input signal, and a correction section configured to perform correction to match phases of the input signal and the output signal from which the DC offset components have been removed, and to match gains of the input signal and of the output signal, the first detection section comparing a waveform of the input signal to a waveform of the output signal, and a second detection section to detect a mismatch between the DC offset component included in the input signal that is input into the removal section and the DC offset component included in the output signal that is input into the removal section.

An amplifier performs analog amplification on a signal I_A with a gain corresponding to a state GS and outputs the amplified signal as a signal M_A. An ADC converts the signal M_A to a digital signal and outputs the digital signal as a signal M_D. Analog comparators and a down-determination unit detect that the signal M_A exceeds a first level, and cause the state GS to transition to a state of gain of the next lower stage. Digital comparators and an up-determination unit detect that the signal M_D has been continuously lower than a second level for a predetermined period, and cause the state GS to transition to a state of gain of the next higher stage. The restoration circuit performs digital amplification on the signal M_D with a gain corresponding to the gain of the amplifier and outputs the amplified signal as a signal O_D.

A system and method in an audio signal electrical circuit including a feedback loop with a digital filter coupled to a current digital to analog converter (IDAC) includes providing an output signal from the IDAC to analog elements of the audio signal electrical circuit, the output signal from the IDAC based upon a reference signal input to the IDAC when an output of the digital filter is not input to the IDAC. The system and method also include comparing an output signal of the audio signal electrical circuit to a reference, and calibrating the audio signal electrical circuit to correspond the output signal of the audio signal electrical circuit to the reference. Calibration of the audio signal electrical circuit enables more precise control of a cut-off frequency of a microphone signal when the output of the digital filter is input to the IDAC.

A sound pickup method includes splitting a sound pickup signal of a microphone of which sound pickup in a predetermined range is blocked by an acoustic obstacle, into a plurality of sound pickup signals and subjecting at least one sound pickup signal among the plurality of sound pickup signals to band limitation processing, and comparing characteristic amounts of the plurality of sound pickup signals including the sound pickup signal after being subjected to the band limitation processing and controlling a gain of the microphone in accordance with a result of comparing the characteristic amounts.

Methods and systems are provided for controlling rail-voltages for amplifier output stages. In some examples, a method may include receiving sets of data values (e.g., at a power-supply control circuitry) for control of a rail voltage of an amplifier output stage. The method may also include determining that the receipt of a pending set of data values has been interrupted. Then, upon the determination that the receipt of the pending plurality of data values has been interrupted, the method may include decreasing the rail voltage to a non-boosted rail-voltage level.

A gaming unit and producing a game-audio output of a varying volume level and a chat-voice output is connected to headphones adapted to be worn by a player of the unit and connected to the gaming unit for making the chat-voice output and the game-audio output audible to the player. A circuit or software associated with the headphones can increase the chat-voice volume level generally proportionately to the game-audio volume level.