Abstract: Techniques are described for dynamically changing a power draw from a power source of a portable device based on an audio output of the portable device. In an example, the portable device determines that an audio signal to be output by the portable device is associated with an audio mode. The portable device sets a voltage of a power converter of the portable device to a voltage level based at least in part on the audio mode. An amount of power is supplied from a power source of the portable device to the power converter based at least in part on the voltage level. In addition, the portable device outputs the audio signal based at least in part on the amount of power.

Abstract: A speech signal leveling system and method include generating an output signal by applying a frequency-dependent or frequency-independent controllable gain to an input signal, the gain being dependent on a gain control signal, and generating at least one speech detection signal indicative of voice components contained in the input signal. The system and method further include generating the gain control signal based on the input signal and the at least one speech detection signal, controlling the controllable-gain block to amplify or attenuate the input signal to have a predetermined mean or maximum or absolute peak signal level as long as voice components are detected in the input signal.

Abstract: Provided are an electronic device and method for managing the perceived loudness of an input audio signal. The electronic device includes a communication unit configured to communicate with internal units and external devices and receive an audio source signal; a loudness adjustment unit configured to receive the audio source signal from the communication unit and obtain an input audio source signal from the audio source signal; a noise separator configured to separate noise from the input audio source signal; a voice booster configured to boost an output audio signal received from the loudness adjustment unit; a storage unit storing instructions; and at least one processor configured to communicate with the communication unit, the loudness adjustment unit, the noise separator, the voice booster, and the storage unit and control operations thereof by executing the stored instructions.

Abstract: An audio processing circuit includes a cascade operational amplifier circuit, an output node, and a pull-down circuit. The cascade operational amplifier circuit includes a first operational amplifier circuit and a second operational amplifier circuit. The first operational amplifier circuit includes a main operational amplifier and a secondary operational amplifier that are connected in parallel. The pull-down circuit is configured to pull down a voltage at the output node after the first operational amplifier circuit is turned on. The second operational amplifier circuit is configured to, after the secondary operational amplifier is turned on, control a voltage gain of the secondary operational amplifier to change gradually from low to high.

Abstract: A pop sound suppression method, an audio output circuit, and a terminal suppress a pop sound that is generated when an audio output circuit is in an alternating current (AC) coupling structure. The output circuit includes an output power amplifier, a common-mode voltage buffer, a reference voltage generation circuit, a powered-on pop sound suppression switch, and a common-mode switch. The powered-on pop sound suppression switch is configured to control, in a power-on process of the audio output circuit, a voltage level of an output node to be zero. The common-mode switch is configured to control, when a reference voltage level of the reference voltage generation circuit is zero, the voltage level of the output node to be equal to the reference level.

Abstract: An audio codec circuit includes: an audio processing circuit; an output driver circuit for generating an analog output signal based on the output of the audio processing circuit; an analog signal pin for outputting the analog output signal to an active amplifier; a multifunction signal pin for providing different signal transmission functionalities according to the configuration of the audio processing circuit; at least one de-pop switch arranged between the analog signal pin and a first fixed-voltage terminal or between the multifunction signal pin and a second fixed-voltage terminal; and a de-pop switch control circuit, coupled with the audio processing circuit and the at least one de-pop switch, arranged to operably control the at least one de-pop switch based on the instruction from the audio processing circuit.

Abstract: A receiver and a program capable of, when they have received a pulse noise together with a reception signal, improving quality of the reception signal are provided. A receiver according to present disclosure includes a received-signal amplification circuit configured to amplify a received signal, a gain control circuit configured to set a gain setting value for an AGC operation in the received-signal amplification circuit, the AGC operation being an operation for making an amplitude of an amplified received signal fall within a predetermined range, and a pulse detection circuit configured to monitor a change in the gain setting value and detect whether or not a pulse noise is contained in the received signal based on whether or not the change in the gain setting value meets a predetermined condition.

Abstract: A circuit and a receiver comprising the circuit, the circuit is able to either feed a received signal directly to the receiver coil or amplify the signal before transmission to the coil. The circuit receives a supply power and amplifies the input signal if the supply power exceeds a threshold value.

Abstract: The present disclosure discloses an audio output circuit including an audio power amplifier, a mute control circuit and a microcontroller, the audio power amplifier includes a power input terminal, a mute control terminal and an audio signal output terminal, the power input terminal is used to connect a power supply to obtain a power supply voltage, the mute control terminal is connected with the microcontroller through the mute control circuit and is grounded by a pull-down resistor, the audio signal output terminal is used to output an audio signal, the mute control circuit is also connected to the power supply for disconnecting the mute control terminal from the microcontroller when the power supply voltage is less than a preset voltage. The present disclosure also provides an audio device. According to the present disclosure, it is possible to effectively prevent the POP sound of the speaker of the audio device.

Abstract: In accordance with an embodiment, a method includes disabling a first electronic switch connected in series with a primary winding of a transformer in a power converter circuit if an auxiliary voltage across an auxiliary winding of the transformer is outside a predefined voltage range. The power converter circuit further includes a secondary winding of the transformer, and a rectifier circuit connected between the secondary winding and an output, where the rectifier circuit comprises a second electronic switch.

Abstract: An electronic device comprising: a memory; a headphone jack; and at least one processor operatively coupled to the memory, configured to: detect an impedance of a first portion of the headphone jack; and detect whether a foreign substance is present in the headphone jack based on the impedance of the first portion of the headphone jack.

Abstract: An AV device including a first signal transmitter configured to output a video signal and a first audio signal corresponding to the video signal to a display device; a first signal receiver configured to receive a feedback signal of the first audio signal from the display device; a second signal transmitter configured to output a second audio signal corresponding to the video signal; and a controller configured to determine a processing delay time of the display device by comparing the first audio signal and the feedback signal, and control the second signal transmitter to delay the output of the second audio signal based on the determined processing delay time.

Abstract: An audio processing integrated circuit chip, such as codec chip, includes at least one port output circuit configured to generate an audio signal to drive an external audio device and a PC beep circuit configured to receive a PC beep signal and to apply the received PC beep signal to an input of the at least one port output circuit. The chip further includes a control circuit configured to detect activity of the PC beep signal and to enable and/or disable the at least one port output circuit responsive to the detected activity.

Abstract: A communication device and method for adapting to audio accessories are provided. The communication device includes a memory; a first microphone, a connector for receiving data from an accessory device having a second microphone, and a processor interconnected with the memory, the microphone and the connector. The processor is configured to receive audio input and, when the audio input originated at the second microphone, to automatically apply equalization settings corresponding to the second microphone.

Abstract: A grounding switch is described which operates properly even in the presence of negative voltages on a signal line. The grounding switch uses isolated field effect transistors that have their substrates tied to different voltages. The isolated field effect transistor has a gate voltage and substrate voltage which can be pulled down to a negative voltage when the signal line has a negative voltage allowing the switch to remain open even with a negative voltage.

Abstract: A driver controller comprising a state machine for controlling transitions between a plurality of states. An output switch for providing a low impedance path to ground during transition periods. An output stage for decoupling output signal from driver amplifier during the transition periods.

Abstract: A circuit for suppressing audio output noise and an audio output circuit are provided. The circuit for suppressing audio output noise includes: a detecting circuit, configured to detect output voltages of output stages of an audio power amplifier; a control circuit, configured to output at least one control signal, the control signal is related to detection results of the detecting circuit; and a compensating circuit, configured to compensate at least one output stage of the audio power amplifier which includes a differential circuit based on the at least one control signal output by the control circuit, to make parameters of the differential circuit symmetrical or approach symmetrical. Based on detection results of the output stage voltages, the differential circuit in the output stages of the audio power amplifier is compensated. The circuit for suppressing audio output noise has a wider application scope and it is easy to design the circuit.

Abstract: A purpose of the invention is to provide a noise gate that can output an audio signal in which only a stationary noise is removed, without degrading an utterance voice of a speaking person. A sound collection device 1 includes an FFT processing unit 11, the noise gate 12, and an IFFT processing unit 13. The sound collection device 1 transforms a collected audio signal NET into a frequency spectrum NE?N by using the FFT processing unit 11. The noise gate 12 estimates a noise spectrum N?N of a stationary noise based on the frequency spectrum NE?N of the audio signal. The noise gate 12 decreases a signal level (a gain) of the audio signal in a case where a signal level ratio of the frequency spectrum NE?N of the audio signal to the noise spectrum N?N is less than a threshold value, and outputs the audio signal.

Abstract: A signal output device includes: a control circuit for receiving at least a first input control signal and outputting an output control signal according to at least the first input control signal, wherein the first input control signal has a first signal segment followed by a second signal segment, and a voltage level of the first signal segment is unknown; and a driver circuit, operated according to a supply power, for receiving the output control signal from the control circuit; wherein a voltage of the supply power is settle before the second signal segment of the first input control signal is received by the control circuit; when the supply power is turned on, the driver circuit operates under a specific power state; and when the second signal segment of the first input control signal is received by the control circuit, the driver circuit keeps operating under the specific power state.

Abstract: A selector selects an analog audio signal input to one input port from among analog audio signals input to multiple input ports according to an instruction from the user. An analog gain control circuit amplifies the analog audio signal received from the selector, with a corresponding one of the gains set for the respective input ports. An analog gain control circuit is configured to gradually change its gain when the gain is switched. An A/D converter converts an output signal of the analog gain control circuit into a digital audio signal. A first audio signal processing circuit is monolithically integrated on a signal semiconductor substrate.

Abstract: A device implementing a scheme for reduction of pop-up noise is disclosed. The device comprises an audio sub-system (100) having an integrator (112) for amplifying an input signal (133) and a modulation circuit (114) including one or more comparators. The audio subsystem (100) is further provided with a feedback loop (142) across the integrator (112) and the modulation circuit (114) to calibrate an offsets outputs of the integrator (112) and the modulation circuit (114). The feedback loop (142) includes an integrator-offset loop (202) across the integrator (112) to calibrate an offset (136) in the output of the integrator (112), and an offset calibration loop (302) across the modulation circuit (114) to calibrate an offset (140) in the output of the modulation circuit (114).

Abstract: Pop/clock noise reduction circuitry is disclosed for audio output circuitry. After audio output circuitry is enabled, reference voltage generator circuitry is then enabled to produce a reference voltage that ramps from a first voltage level to a second voltage level at a smooth rate. The ramping reference voltage is applied to the input of the audio output circuitry to reduce or prevent pop/click noise for the audio output circuitry. Further, negative offset control circuitry can also be used to provide a negative offset input to the audio output circuitry to remove initial step-up voltage levels that may exist at operational power-up for the audio output circuitry. Still further, current control circuitry can also be used that limits the available current flowing to the output node for the audio output circuitry, thereby further reducing and/or preventing potential pop/click noise in the audio output signals.

Abstract: An audio system that reduces or eliminates click and pop noise during power up and power down operations. In particular, the audio system includes an amplifier with an input adapted to receive an input audio signal and an output adapted to produce an amplified output audio signal for an associated speaker. The audio system further includes a noise reduction circuit adapted to smoothly apply and remove a DC voltage to and from the output of the amplifier in a manner that reduces or eliminates click and pop noise from being generated by the associated speaker. The DC voltage at the output of the amplifier may be derived from a DC reference voltage source and/or from the input audio signal.

Abstract: Provided are methods and systems for noise suppression within multiple time-frequency points of spectral representations. A multi-feature cluster tracker is used to track signal and noise sources and to predict signal versus noise dominance at each time-frequency point. Multiple features, such as binaural and monaural features, may be used for these purposes. A Gaussian mixture model (GMM) is developed and, in some embodiments, dynamically updated for distinguishing signal from noise and performing mask-based noise reduction. Each frequency band may use a different GMM or share a GMM with other frequency bands. A GMM may be combined from two models, with one trained to model time-frequency points in which the target dominates and another trained to model time-frequency points in which the noise dominates. Dynamic updates of a GMM may be performed using an expectation-maximization algorithm in an unsupervised fashion.

Abstract: It is inter alia disclosed to determine a peak energy level for an audio frame of a band limited audio signal; determine that the peak energy level is a maximum peak energy level by determining that the peak energy level exceeds a peak energy level determined for at least one neighboring audio frame by a first predetermined energy threshold value; classify a region of audio samples associated with the maximum peak energy level as an audio click; and suppress audio samples of the region of audio samples classified as an audio click by multiplying at least one audio sample of the audio frame with a sample wise suppressor gain function.

Abstract: A class D amplifier receives and amplifies a differential analog signal which is then differentially integrated. Two pulse width modulators generate pulse signals corresponding to the differentially integrated analog signal and two power units generate output pulse signals. The outputs the power units are coupled to input terminals of integrators via a resistor feedback network. An analog output unit converts the pulse signals to an output analog signal. The differential integration circuitry implements a soft transition between mute/un-mute. In mute, the integrator output is fixed. During the soft transition, the PWM outputs change slowly from a fixed 50% duty cycle to a final value to ensure that no pop noise is present in the output as a result of mode change.

Abstract: An amplifier may include two or more pulse-width modulators (PWMs) controlling respective sets of switches to produce an amplified version of a source signal. The clocking for the amplifier may be controlled to delay signal processing within the PWMs relative to one another in time, thereby providing an effective time offset between the absolute moment in time of the edge transition of the controlling signals to the respective sets of switches. The PWMs may include a decrementor that counts down to zero from the next PWM duty-cycle value when a new data sample is detected, beginning a new count when the next sample is present. The PWM output may correspond to the counter value, outputting a pulse when the counter value is nonzero. A “data-sample-ready” signal may be decoded from a master counter, which may be clocked based on the high speed PWM clock, and the delay mechanism may be based on adjusting the decode value to determine when the PWM should initialize to the next data sample.

Abstract: A de-pop controller and method thereof are provided. The controller includes an amplifier and a comparator. The amplifier receives and amplifies an audio input signal, and then outputs an audio output signal. The comparator, coupled to the amplifier, receives a transient indication signal. The comparator compares the transient indication signal with a reference voltage, and the comparison result is then applied to control the driving ability of the amplifier for de-popping.

Abstract: Systems and methods for controlling adaptivity of noise cancellation are presented. One or more audio signals are received by one or more corresponding microphones. The one or more signals may be decomposed into frequency sub-bands. Noise cancellation consistent with identified adaptation constraints is performed on the one or more audio signals. The one or more audio signals may then be reconstructed from the frequency sub-bands and outputted via an output device.

Abstract: A device for grounding pop-click noise may include an output block configured to generate an output signal at an output node. A switch circuit coupled to the output node may be configured to be operable to couple the output node to a ground potential. The switch circuit may include a first and a second transistor. A drain, a source, and a gate node of the first transistor may be coupled to the output node, a drain node of the second transistor, and a first control signal, respectively. A drain, a source, and a gate node of the second transistor may be coupled to a source node of the first transistor, the ground potential, and a second control signal, respectively. The first and the second control signals may operate the switch circuit to couple the output node to the ground potential during a pre-determined period associated with the pop-click noise.

Abstract: A switch can be configured to receive a first signal at a first input and provide an output signal at an output, depending on a state of the switch. A switch state change can be delayed until an indication of a requested switch state different than a current switch state is received and the first signal reaches a threshold.

Abstract: Self-grounded circuitry (10) includes a signal channel conducting an output voltage (VOUT1). A charge pump (2) powered by a reference voltage (VDD) produces a control voltage (VCP). The control signal is at a low level if the reference voltage is low and is boosted to a high level if the reference voltage is high. A ground switch circuit (15) includes a depletion mode transistor (MP1) having a source coupled to the output voltage, a gate coupled to the control voltage, and a drain coupled to ground. The transistor includes a well region (4-1) and a parasitic substrate diode (D3-1).

Abstract: A mobile communication terminal is provided including an audio processing unit, a speaker, a connecting unit that connects to an external audio output device and indicates whether the external audio output device is connected, and a control unit configured to, while in a silent mode, control the audio processing unit to reproduce a music file and to output audio signals, corresponding to the reproduced music file, through the speaker, the silent mode being a mode wherein a vibration signal is generated upon receiving an incoming call, if the external audio output device is connected to the connecting unit, output the audio signals to the external audio output device, and if the external audio output device is disconnected from the connecting unit while the audio signals are being output to the external audio output device, control the display unit to display a user interface for continuing reproduction of the music file.

Abstract: An audio device is capable of switching between a first state and a second state. The audio device comprises a power supply, a delay module, a control module, a processor, and an audio-playing module. The power supply provides a working voltage when the audio device is in the second state. The delay module is connected between the power supply and the control module, and outputs a delay signal when the audio device switches between the first state and the second state. The control module for outputting a driving signal is prevented from outputting driving signal in response to the delay signal, and the processor is enabled in response to the delay signal.

Abstract: A POP noise suppressing circuit includes a blocking capacitor, an outputting element connected to the blocking capacitor, a current generating unit, a charging unit connected to the current generating unit, a discharging unit connected to the current generating unit, a switching unit connected to the charging unit and the discharging unit and a power amplifying unit connected between the switching unit and the blocking capacitor. The current generating unit provides two slowly increasing currents respectively to the charging unit and the discharging unit. The switching unit is for switching between the charging unit and the discharging unit. The charging unit forms a charging current. The discharging unit forms a discharging current. The voltage of the blocking capacitor increases smoothly in a process of powering on and decreases smoothly in a process of powering off. A POP noise suppressing method is also provided.

Abstract: A method for reproducing a music file of a mobile communication terminal includes outputting a confirmation message for determining whether a music file is to be reproduced if reproduction of the music file is requested during the manner mode of the mobile communication terminal, and reproducing the music file if an external output device is connected to the mobile communication terminal. Since a user can reproduce music files without any complex key manipulation, even during the manner mode of the mobile communication terminal, the user can listen to desired music easily, thereby improving the convenience of the mobile communication terminal.

Abstract: A method and apparatus are provided for processing a received digital radio broadcast signal to efficiently remove signal interference artifacts from digital and/or analog signals by using signal quality information extracted from audio samples in one or more buffered audio frames to detect audio frames containing clipped noise artifacts and weaker noise artifacts and to selectively apply anti-interference processing to remove the signal interference artifacts.

Abstract: A system and method for sharing a designated audio signal may reproduce the designated audio signal via transducer into an acoustic space. The designated audio signal may be a recorded audio signal, an encoded audio signal, a streamed audio signal and an audio signal component of a multi-media content item. An input audio signal may be received representing a sound field in the acoustic space. One or more microphones may receive the input audio signal. A component contributed by the reproduced designated audio signal may be suppressed in the input audio signal. An echo suppressor may suppress the recaptured designated audio signal. The designated audio signal may be mixed with the suppressed input audio signal to generate an uplink audio signal. The designated audio signal mixed with the suppressed input audio signal may not include artifacts caused by the transducer, the microphone and the acoustic space.

Abstract: A phantom power circuit has a detection circuit and a limiting circuit, the detection circuit detecting a pulse current generated in association with connection or disconnection of a condenser microphone, the limiting circuit limiting the output of the condenser microphone. The detection circuit detects a pulse current generated between input terminals of the condenser microphone. The limiting circuit reduces the output from the condenser microphone when the detection circuit detects the pulse current.

Abstract: A switch controller is provided that uses one or more capacitors to generate a slow turn on/slow turn off switch control signals to suppress audible switching noise in an audio switch. In some embodiments, an analog inverter and a capacitor are used to generate the switch control signals, while in other embodiments two capacitors are used to generate the switch control signals. To conserve power between switching states, routing logic is provided that ties the switch control signals to respective voltage rails and disables selected portions of the switch controller.

Abstract: A motherboard includes a motherboard power supply connector and a time delay circuit. The motherboard power supply connector connects a power supply unit. The motherboard power supply connector has a power supply on pin and a power good pin. The power good pin is configured for receiving a power good signal from the power supply unit. The time delay circuit has an input terminal and an output terminal. The input terminal is configured for receiving a power supply on signal. The output terminal is connected to the power supply on pin and is configured for sending the power supply on signal to the power supply on pin after a time delay determined by the time delay circuit.

Abstract: An adaptive power control monitors the noise level within a primary acoustic signal and compares the noise level to a threshold. If the noise level is lower than the threshold, a noise suppression system is deactivated and bypass filtering and cross fading are enabled. If the noise level is higher than the threshold, the noise suppression system is activated.

Abstract: A signal processing apparatus includes: one or more detection means for detecting movement of a diaphragm of a speaker in correspondence with feedback methods that are different feedback methods; analog-to-digital conversion means for converting one or more detection signals acquired by the detection means into a digital form; feedback signal generating means for generating feedback signals corresponding to the feedback methods using the digital detection signals; synthesis means for combining an audio signal to be output as a driving signal of the speaker with the feedback signals; correction equalizer means for setting an equalizing characteristic to allow a sound reproduced by the speaker to have a target frequency characteristic by changing the digital audio signal; feedback operation setting means for setting feedback methods in which a feedback operation up to combining the audio signal with the feedback signal is performed and the feedback operation is not performed equalizing characteristic changing a

Abstract: The present disclosure provides an earphone power amplifier, including a ground contact connected to a ground wire of an earphone, a left sound channel power amplifying circuit connected to a left sound channel of the earphone, and a right sound channel power amplifying circuit connected to a right sound channel of the earphone. The left sound channel power amplifying circuit includes a first operational amplifier and a first positive feedback exported from an input end of the first ferrite bead to an in-phase input end of the first operational amplifier, the right sound channel power amplifying circuit includes a second operational amplifier and a second positive feedback exported from the input end of the first ferrite bead to an in-phase input end of the second operational amplifier.

Abstract: An apparatus for a portable electronic device for receiving a jack of a headset, the jack including a set of lines, the set of lines including at least one audio line, a ground signal and a microphone signal line, the apparatus comprising a set of switches for receiving the ground signal line and the microphone signal line and a sensing circuit for reducing induced noise from the headset, wherein the sensing circuit is located between the set of switches and the microphone signal line and ground signal line.

Abstract: According to some aspects, an electronic device adapted to provide audio output via an audio system. The electronic device includes an audio jack adapted to be coupled to the audio system. The audio jack includes a line-out for sending audio signals to the audio system and a ground return line. The electronic device also includes a ground resistor between the ground return line and a ground node. The ground resistor has a resistance selected to reduce ground current on the ground return line when the electronic device is being charged without significantly adversely affecting the quality of the audio output.

Abstract: Provided is an audio output device capable of preventing noises and improving the S/N ratio even if no audio signal is inputted in the middle of the input of audio signals, or even if an audio-signal input state and a no-signal state are alternately repeated. In the provided audio output device, a multiplier is provided on the input side of each of the delayers. Each multiplier multiplies the addition output of the corresponding one of adders by a multiplier coefficient supplied by the coefficient counter. If there is no input of digital audio signals into a ?? modulator, the counter control circuit decreases the output of the coefficient counter down to 0 stepwise at predetermined intervals.

Abstract: An amplifier with improved noise reduction is disclosed. In one implementation, an amplifier is provided that includes a main output stage configured to output an amplified signal at a main output terminal, a secondary output stage configured to output a copy of the amplified signal at a secondary output terminal, and a signal coupler configured to provide a variable resistance coupling between the secondary output terminal and the main output terminal to reduce noise at the main output terminal.

Abstract: Pop/clock noise reduction circuitry is disclosed for audio output circuitry. After audio output circuitry is enabled, reference voltage generator circuitry is then enabled to produce a reference voltage that ramps from a first voltage level to a second voltage level at a smooth rate. The ramping reference voltage is applied to the input of the audio output circuitry to reduce or prevent pop/click noise for the audio output circuitry. Further, negative offset control circuitry can also be used to provide a negative offset input to the audio output circuitry to remove initial step-up voltage levels that may exist at operational power-up for the audio output circuitry. Still further, current control circuitry can also be used that limits the available current flowing to the output node for the audio output circuitry, thereby further reducing and/or preventing potential pop/click noise in the audio output signals.

Abstract: An amplifier is disclosed, wherein the output stage is split between a primary output stage and a secondary stage. To minimize or eliminate any audible plop when the amplifier is switched on, the primary stage is connected, and the second stage is gradually connected using a switch. The gradual connection can be by means of varying the pulse-density of a pulse wave modulation on the switch, from fully open (0% pulse-density) to fully closed (100%). The inverse process can minimize or eliminate plop during switch-off. Separate feedback loops are switchable, from the primary and secondary stages; in a DC-coupled embodiment, the feedback loop from the secondary stage may include DC-offset cancelling circuitry, to both reduce or eliminate the plop and avoid and DC-offset current through the speaker.