With Amplifier Patents (Class 381/120)
  • Patent number: 9257944
    Abstract: Disclosed is a differential microphone pre-amplifier circuit (120) for providing an amplified differential signal at a first (A) and a second (B) output terminal of the microphone pre-amplifier (120), including a first voltage controlled current generator (101), a second voltage controlled current generator (102) and a third voltage controlled current generator (103) all being configured to receive, amplify and convert a voltage signal generated by an associated microphone (110) to a current signal output.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: February 9, 2016
    Assignee: Research Electronics Leksand AB
    Inventor: Sven-Åke Eriksson
  • Patent number: 9252727
    Abstract: A peripheral apparatus, for connecting to a first or a second transmission port of an electronic device, includes a signal transmission interface, a triggering unit, an amplifying unit and an adjusting unit. The signal transmission interface, coupled to the first or the second transmission port, includes a first and a second group of pins. The triggering unit is coupled to the signal transmission interface. When the signal transmission interface is coupled to the first or the second transmission port, the triggering unit outputs a first or a second voltage level signal, respectively. The amplifying unit is coupled to the signal transmission interface and a functional unit. The adjusting unit, coupled to the signal transmission interface, the triggering unit, the amplifying unit and the functional unit, changes an output power transmitted from the amplifying unit to the functional unit according to the first or the second voltage level signal.
    Type: Grant
    Filed: February 13, 2013
    Date of Patent: February 2, 2016
    Assignee: KYE SYSTEMS CORP.
    Inventors: Jen-Fu Huang, Chih-Chien Liao, Nine-Ren Kang
  • Patent number: 9251775
    Abstract: An electronic signal processor for processing signals includes a complex first filter, one or more gain stages and a second filter. The first filter is characterized by a frequency response curve that includes multiple corner frequencies, with some corner frequencies being user selectable. The first filter also has at least two user-preset gain levels which may be alternately selected by a switch. Lower frequency signals are processed by the first filter with at least 12 db/octave slope, and preferably with 18 db/octave slope to minimize intermodulation distortion products by subsequent amplification in the gain stages. A second filter provides further filtering and amplitude control. The signal processor is particularly suited for processing audio frequency signals.
    Type: Grant
    Filed: June 10, 2014
    Date of Patent: February 2, 2016
    Inventor: Jeffrey Arnold
  • Patent number: 9231543
    Abstract: A power converter has an output that is coupled in parallel with an energy reservoir circuit and a power supply node of an audio power amplifier. The converter can set an upper limit on its input supply current that is variable in accordance with a control input. A controller is to produce a signal, coupled to the control input of the power converter, that is responsive to a measure of input supply voltage of the power converter and either output voltage of the power converter or output power of the amplifier. Other embodiments are also described and claimed.
    Type: Grant
    Filed: January 13, 2014
    Date of Patent: January 5, 2016
    Assignee: Apple Inc.
    Inventors: Roderick Hogan, Joseph J. Curcio, Nathan A. Johanningsmeier, Casey L. Hardy
  • Patent number: 9225309
    Abstract: The invention relates to an audio amplifier (1) for amplifying an input signal into an output signal, comprising an output amplification stage (6), wherein the output amplification stage (6) for the amplification of an intermediate signal into the output signal is designed as an amplifier operating in switching operation, and further comprising a limiter device (4), which from a programming and/or a circuit design point of view is designed to generate the intermediate signal on the basis of the input signal, wherein the level of the intermediate signal is always limited by a maximum load as a function of a settable maximum output and a load impedance which is coupled and/or can be coupled the audio amplifier or equivalent parameter thresholds such that the output signal does not exceed the maximum load at the load impedance, or the equivalent parameter thresholds, independently of the input signal.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: December 29, 2015
    Assignee: Robert Bosch GmbH
    Inventors: Josef Taffner, Gregor Sauer, Christian Glueck, Josef Plager, Peter Hallstein
  • Patent number: 9210508
    Abstract: Novel active phantom-powered ribbon microphones that provide switchable proximity effect response filtering for voice and music applications are disclosed with unique adjustable interfaces. In one embodiment of the invention, a slider-based full frequency response vs. low frequency response and high pass filtering adjustment interface on a surface of a microphone casing provides a convenient switching between a “Music” mode and a “Voice” mode, wherein the “Voice” mode reduces the undesirable proximity effect in an active phantom-powered ribbon microphone, when a sound source is situated overly close to the active phantom-powered ribbon microphone. Furthermore, in one embodiment of the invention, a slider-based or a knob-based variable voice mode adjustment interface can also be integrated on a surface of a microphone casing to provide various preset levels of low frequency reduction and/or proximity effect response filtering when the “Voice” mode is enabled.
    Type: Grant
    Filed: January 19, 2014
    Date of Patent: December 8, 2015
    Inventor: Rodger Cloud
  • Patent number: 9203365
    Abstract: Audio input tubes and power output tubes in a vacuum tube amplifier are powered and controlled by solid state controllers. The solid state controllers sample incoming audio and anticipate and apply changes and biases in grid and plate voltages before the audio signals arrive in the power output tubes. Any mains voltage is filtered, regulated and converted to a standard voltage which is converted to plural DC voltages that are applied to sensors, tube cathode heaters, grids and plates and are varied on screen grids and plates with stepped increases and autobias. The solid state components have sensors and feedback to control voltages. Sensed overvoltages fold back power to the solid state devices and heaters, screens and plates to provide uninterrupted amplification without endangering the tubes or components.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: December 1, 2015
    Inventors: Michael B. Milbert, Alfred N. Milbert
  • Patent number: 9154098
    Abstract: A true ground amplifier circuit in which a voltage sensor senses the output voltage and generates a binary output which indicates whether the output is above or below a threshold. A variable gain feedback system generates a feedback signal for combination with the digital input, thereby to provide offset cancellation. The variable gain is reduced over time to provide offset cancellation during an initial period of time of operation of the amplifier circuit. This provides offset cancellation during a start-up period, for example.
    Type: Grant
    Filed: April 22, 2014
    Date of Patent: October 6, 2015
    Assignee: NXP B.V.
    Inventors: Han Martijn Schuurmans, Maarten van Dommelen
  • Patent number: 9148719
    Abstract: A portable electronic device having a speaker module is provided. The speaker module includes: a speaker unit; a back chamber; a channel coupled between the speaker unit and the back chamber; and a porous material filled inside at least a portion of the front chamber, the back chamber, and/or the channel, for improving and extending bass performance and relieving a channel effect caused by the channel. Moreover, the portable electronic device is advantageously able to compensate a resonance degradation caused by the porous material.
    Type: Grant
    Filed: March 6, 2013
    Date of Patent: September 29, 2015
    Inventors: Hann-Shi Tong, Chun-Min Lee, Lei Chen, Yu-Sheng Lee, Chih-Chiang Cheng
  • Patent number: 9055358
    Abstract: A speaker device including: a hollow case; a drive unit housed in the case and configured to cause a diaphragm to vibrate; and a curved diaphragm having a flat plate curved and arranged to stand in an upright position on an upper surface of the case, wherein a diaphragm of the drive unit is exposed at a part of a surface of the case, and a part of a base end of the curved diaphragm abuts on the diaphragm of the drive unit, and the curved diaphragm is compressively deformed through a standing pole arranged to extend between a tip end of the curved diaphragm and the case, whereby vibration of the diaphragm of the drive unit is allowed to propagate to the curved diaphragm and the case so that sound is allowed to come out of the diaphragm of the drive unit, the curved diaphragm, and the case.
    Type: Grant
    Filed: March 6, 2014
    Date of Patent: June 9, 2015
    Assignee: GEM Impact Inc.
    Inventors: Yutaka Sato, Norio Nagai, Norihiko Hibino, Aiko Hibino
  • Patent number: 9049519
    Abstract: A horn loudspeaker with gain shading. The horn loudspeaker includes an acoustic horn. The acoustic horn includes side walls, for determining the horizontal dispersion angle of the acoustic horn, top and bottom walls, for determining the vertical dispersion angle of the acoustic horn, and a plurality of acoustic drivers coupled to the acoustic horn by a diffraction slot having segments. Each of the segments is separated from the adjacent segments by less than one half of the wavelength of the highest frequency of the operational range of the horn loudspeaker. The horn loudspeaker further includes circuitry for transmitting an audio signal to the plurality of acoustic drivers, the circuitry comprising a first signal attenuation element electrically coupling an audio signal input element and a first of the acoustic drivers.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: June 2, 2015
    Assignee: Bose Corporation
    Inventors: David Edwards Blore, Paul F. Fidlin, Soichiro Hayashi
  • Patent number: 9042578
    Abstract: A microphone amplifier comprises a microphone terminal for connecting a microphone, particularly a MEMS microphone, and an amplifier circuit with an amplifier input that is connected to the microphone terminal, and with an amplifier output that is connected to an output of the microphone amplifier. The amplifier circuit is designed to amplify an input signal present at the amplifier input in order to generate an output signal at the amplifier output. The microphone amplifier further comprises an overload circuit that is designed to detect an overload state within the amplifier circuit and to connect the amplifier input via a switching element, in particular with a low impedance, to a reference potential terminal if the overload state is detected for more than a predetermined time span.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: May 26, 2015
    Assignee: ams AG
    Inventor: Wolfgang Dünser
  • Patent number: 9036836
    Abstract: Disclosed is a technique for reducing noise superimposed on an output signal while keeping loop gain constant without increasing the circuit scale and without changing the transfer function of the amplifier apparatus (frequency characteristics of gain and phase). According to the technique, there are included a power-supply voltage control unit 7 for detecting the amplitude level S9 of an input audio signal S1 and outputting power with a voltage value indicated by target set voltage value information Vs corresponding to this amplitude level S9, and a PWM modulation unit 2 including a PWM converter 23 for converting the pulse width of the input audio signal S1 and a correction unit for correcting the signal modulated by the PWM converter 23. The PWM modulation unit 2 corrects the pulse width of a PWM signal S5 modulated by the PWM converter 23 so that the correction unit will cancel out a change in amplification gain of a power amplification unit 4 according to the target set voltage value information Vs.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: May 19, 2015
    Inventors: Mingxue Zhang, Seigo Ozaki, Tsuyoshi Haga
  • Patent number: 9036835
    Abstract: An apparatus is described that includes an audio power amplifier having an input and an output. An alternating-current to direct-current power converter is coupled to the audio power amplifier in a single package to supply power to the audio power amplifier.
    Type: Grant
    Filed: November 5, 2007
    Date of Patent: May 19, 2015
    Assignee: AliphCom
    Inventor: David C. Buuck
  • Patent number: 9025793
    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.
    Type: Grant
    Filed: June 20, 2012
    Date of Patent: May 5, 2015
    Assignee: Rohm Co., Ltd.
    Inventor: Mitsuteru Sakai
  • Publication number: 20150109534
    Abstract: A transparent ultrasonic audio speaker includes an emitter and a driver. The emitter can include first and second transparent conductive sheets. The conductive sheets can comprise a base layer and a conductive layer, and can be transparent. The transparent ultrasonic audio speaker can be configured to be positioned on or in place of the display screen of a content device.
    Type: Application
    Filed: October 17, 2013
    Publication date: April 23, 2015
    Applicant: Parametric Sound Corporation
    Inventors: Elwood Grant Norris, Brian Alan Kappus
  • Publication number: 20150110299
    Abstract: A method and device for driving a digital speaker based on code conversion are provided in the invention. The method comprises the steps of: (1) converting input format; (2) performing multi-bit ?-? modulation; (3) thermometer code conversion; (4) dynamic mismatch-shaping processing; (5) pulse width modulation code conversion; and (6) controlling on/off status switching of the MOSFET of a full-bridge power amplification network to drive a digital speaker load sound. The device comprises a sound source, an input format converter, a multi-bit ?-? modulator, a thermometer coder, a dynamic mismatch shaper, a code converter, a multi-channel digital amplifier and a digital speaker load which are connected to each other in sequence.
    Type: Application
    Filed: November 30, 2012
    Publication date: April 23, 2015
    Applicant: Suzhou Sonavox Electronics Co., Ltd.
    Inventor: Dengyong Ma
  • Patent number: 9014396
    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.
    Type: Grant
    Filed: January 31, 2008
    Date of Patent: April 21, 2015
    Assignee: QUALCOMM Incorporated
    Inventor: Guoqing Miao
  • Publication number: 20150104045
    Abstract: An ultrasonic emitter is provided, where at least one of an amplifier, driver circuit, and signal processing circuitry is integrated onto or into the ultrasonic emitter. The ultrasonic emitter may include a backing plate and an amplifier and/or associated processing integrated directly onto the backing plate for amplifying and matching an audio modulated ultrasonic carrier signal to the ultrasonic emitter. The emitter is configured to launch a pressure-wave representation of the audio modulated ultrasonic carrier signal into the air.
    Type: Application
    Filed: October 9, 2014
    Publication date: April 16, 2015
    Inventor: Elwood Grant Norris
  • Publication number: 20150104044
    Abstract: A throat-vibration-type sensor includes a ceramic sheet and a copper sheet received in a box body, wherein the ceramic sheet and the copper sheet are electrically connected to an amplification circuit for voice communications. The volume and thickness of the throat-vibration-type sensor is reduced, the cost thereof is reduced, the assembly thereof is easy, and the reception effect is increased. The throat-vibration-type sensor is combined with a communication hand-free device which includes a control circuit board, a sound amplification device and a battery unit. The throat-vibration-type sensor is used for relieving the interference of external noise. The communication hand-free device combined with the throat-vibration-type sensor avoids the inability of identifying a voice signal because of a wind shear sound caused by a high moving speed of a wearer, to improve the overall utilization efficiency of the communication hand-free device.
    Type: Application
    Filed: March 27, 2013
    Publication date: April 16, 2015
    Inventors: Shio-Shiin Lee, Chih-Hsien Liang, Yu-An He
  • Patent number: 9008322
    Abstract: The present invention concerns an audio amplifier circuit designed to provide an output signal to an audio transducer, said audio amplifier circuit comprising an audio power amplifier designed to receive an audio signal and designed to generate said output signal, a sensor designed to detect an audible sound having at least one noise component, to generate a detected signal. The audio amplifier circuit also includes a processing block configured to receive said detected signal at its input and to generate an off signal at its output, the latter being located at the input of said audio power amplifier. The processing block processes the detected signal according to said input signal to identify said noise component of said detected signal to generate a reference signal. The processing block generates the off signal when the value of said input signal is lower than the value of said reference signal.
    Type: Grant
    Filed: May 30, 2012
    Date of Patent: April 14, 2015
    Assignee: STMicroelectronics S.r.l.
    Inventors: Edoardo Botti, Marco Zanettini, Matteo Bellitra
  • Patent number: 9008319
    Abstract: Sound pressure level limiter with anti-startle feature for audio systems are disclosed. The anti-startle feature may be implemented with a delta incident detector for detecting delta acoustic incidents that exceed a predetermined acoustic startle boundary, a delta limiter for determining an anti-startle gain, and an amplifier to apply the anti-startle gain to the input signal. The delta incident detector may detect delta incidents based on an estimated true SPL delivered by a transducer to a predetermined datum point. The estimated true SPL may be determined by based on a measured receiving frequency response of the transducer. An SPL limiter may also determine an SPL gain in response to detecting an SPL acoustic incident that exceeds a predetermined SPL threshold, and an amplifier may apply the SPL gain to the input signal to reduce it below the threshold.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: April 14, 2015
    Assignee: Plantronics, Inc.
    Inventors: Antony M W. Bayley, William R. Morrell, Iain J. McNeill, Kwangsee A. Woo
  • Patent number: 9008333
    Abstract: A device and methods are provided for a guitar amplifier. In one embodiment, an amplifier includes an overdrive shaping circuit including one or more elements for harmonic shaping of a received signal. The amplifier may also include a power amplifier circuit configured to receive the harmonic shaped signal from the overdrive shaping circuit, wherein the power amplifier circuit includes a switchmode amplifier to amplify the harmonic shaped signal includes one or more elements to increase the output impedance of the switchmode amplifier. An output of the amplifier can output a signal with desired harmonic shaping and a dynamic response.
    Type: Grant
    Filed: May 29, 2012
    Date of Patent: April 14, 2015
    Assignee: Quilter Labs, LLC
    Inventor: Patrick H. Quilter
  • Patent number: 9008334
    Abstract: An audio mixing console comprises a first amplifier, an analogue to digital converter, a second amplifier and a gain range control unit. The first amplifier may receive an analogue audio input signal and amplify the received audio input signal with a first adjustable gain. The analogue to digital converter may receive the amplified analogue audio input signal and generate a digital audio signal by an analogue to digital conversion of the analogue audio signal. The second amplifier may receive the digital audio signal and amplify the received digital audio signal with a second adjustable gain. The gain range control unit may identify a signal level overload at the analogue to digital converter and control the gain of the first and second amplifiers, respectively.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: April 14, 2015
    Assignee: Harman International Industries Ltd.
    Inventor: Richard Ayres
  • Patent number: 9008332
    Abstract: A processing chip for a digital microphone and related input circuit and a digital microphone are described herein. In one aspect, the input circuit for a processing chip of a digital microphone includes: a PMOS transistor, a resistor, a current source, and a low-pass filter. The described processing chip possesses high anti high-frequency interference capabilities and the described input circuit possesses high high-frequency power supply rejection ratio.
    Type: Grant
    Filed: September 29, 2011
    Date of Patent: April 14, 2015
    Assignee: Beijing KT Micro, Ltd.
    Inventors: Wenjing Wang, Jianting Wang, Rongrong Bai, Jing Cao
  • Publication number: 20150098590
    Abstract: A method, computer program product, and computer system for receiving an indication that a first module is operatively connected to a main module, wherein the first module and the main module include hardware modules. A type of speaker operatively connected to the first module is identified. The type of speaker is matched to a speaker profile, wherein the speaker profile includes a predefined sound curve setting. The first module is tuned to the predefined sound curve setting based upon, at least in part, matching the type of speaker to the speaker profile.
    Type: Application
    Filed: October 7, 2014
    Publication date: April 9, 2015
    Inventor: ROBERT OSWELL
  • Patent number: 9000900
    Abstract: A vehicle proximity annunciator device reduces an occurrence of a pop noise without an additional circuit changing an output of a power amplifier. A capacitor is located between a connection point connecting multiple resistances generating a reference voltage and a ground terminal. The capacitor causes a rise-up time of the reference voltage to delay at a start of power supply to a power source terminal. A sound emission signal is increased at substantially a same level of the reference voltage so that a variation of a differential voltage between the reference voltage and the sound emission signal falls in a pre-determined range.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: April 7, 2015
    Assignee: Anden Co., Ltd.
    Inventors: Haruyuki Tsuzuki, Yoshimitsu Ukai, Yukiko Matsubara, Chikara Yamamoto
  • Patent number: 8995691
    Abstract: The embodiments described herein relate to amplifier circuits with power rails. The power rails are generated in response to an input signal, which will typically be an audio signal, and with a sufficient magnitude to power the amplifier and to generate an output signal corresponding to the input signal.
    Type: Grant
    Filed: July 13, 2009
    Date of Patent: March 31, 2015
    Assignee: Audera Acoustics Inc.
    Inventors: John B. French, Andrew Mason
  • Publication number: 20150086044
    Abstract: An audio demonstration kit encourages understanding of audio concepts by enabling children to construct and study speaker performance. In a particular embodiment, the audio demonstration kit includes a paper speaker and instructions. The paper speaker includes a backplate, a suspension, and a diaphragm cut from a single sheet of paper. The demonstration kit may feature an amplifier that is configurable to accommodate various hardware additions as a child is ready for more progressively challenging construction. For example, the amplifier of an embodiment allows single and dual mode operation, as well as drives a rotary motor and is coordinated with a strobe light. The amplifier of an embodiment is synchronized with the strobe light and a moveable platform to create the impression of that jiggling figures attached to the table are dancing. Interfaces with smart phone, recording, and other technologies further enhances and encourages the learning experience.
    Type: Application
    Filed: March 28, 2014
    Publication date: March 26, 2015
    Applicant: Bose Corporation
    Inventor: Lee Zamir
  • Publication number: 20150086041
    Abstract: Embodiments described herein provide for acoustic signatures in a playback system. In some embodiments, a playback device includes an audio processing component configured to receive an audio input signal, receive an acoustic signature signal, generate an audio output signal based on the audio input signal and the acoustic signature signal, and output the generated audio output signal. In some embodiments, the acoustic signature identifies at least one of the playback device or a group of playback devices. Some embodiments additionally include the playback device amplifying the generated audio output signal with one or more amplifiers, and playing the generated audio output signal via one or more speakers.
    Type: Application
    Filed: December 3, 2014
    Publication date: March 26, 2015
    Applicant: Sonos, Inc
    Inventor: Robert Reimann
  • Patent number: 8989407
    Abstract: A channel conversion part (214) performs channel conversion on audio data of a plurality of channels so that the number of channels thereof is converted to an appropriate number of channels for which an acoustic effect can be verified or perceived by audience according to the volume level of reproduced sound, and audio is output only with a required number of channels. In addition, a frequency control part (215) for controlling the operating frequencies of switching regulators (220-223) of audio amplifiers (224-227) also performs frequency control according to the volume level of sound of each channel which performs an audio output.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: March 24, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Teruki Kikkawa, Yasuhiro Matsuura
  • Patent number: 8989406
    Abstract: Embodiments are directed toward user profile based audio adjustment techniques. The techniques are used to render various audio and/or audio/video content having different audio output parameter values in accordance with a user profile that characterizes a user's desired value and/or range of one or more of the output parameter levels.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: March 24, 2015
    Assignees: Sony Corporation, Sony Network Entertainment International LLC
    Inventors: Ling Jun Wong, True Xiong
  • Patent number: 8983086
    Abstract: An output controller and an method for outputting a signal flow to one or more earphone jacks according to a connection status of each earphone jack. The output controller includes an interface unit having more than one earphone jacks and an output control unit. The output control unit includes a signal input terminal for receiving a signal flow, a detector, and a determining module. The detector detects whether each earphone jack is connected with an earphone and outputs one or more detected signals representing the connection status of the earphone jacks. The determining module outputs the signal flow directly to the connected earphone jack if only one earphone jack is connected to the earphone or distributes the signal flow being amplified correspondingly into each connected earphone jack if more than one earphone jack is connected to the earphones.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: March 17, 2015
    Assignees: Fu Tai Hua Industry (Shenzhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Yang Xin, Tsung-Jen Chuang, Jun Zhang, Jun-Wei Zhang, Ren-Wen Huang, Qiang You
  • Patent number: 8983094
    Abstract: An all-in-one audio system includes an audio chip, an audio interface, first and second audio signal amplifiers, a speaker, a woofer, a multi-function controller, a high definition multimedia interface (HDMI), and a switch. The multi-function controller is connected to the audio chip, the switch, the audio interface, the first and second audio signal amplifiers, and the HDMI. When the multi-function controller detects a high definition multimedia signal through the HDMI, the multi-function controller turns off the switch, decodes the high definition multimedia signal into an audio signal, and transmits the audio signal to the audio interface, and the first and second audio signal amplifiers. The first and second audio signal amplifiers amplify the audio signal and output the amplified audio signal to the speaker and woofer.
    Type: Grant
    Filed: November 19, 2010
    Date of Patent: March 17, 2015
    Assignee: Zhongshan Innocloud Intellectual Property Services Co., Ltd.
    Inventor: Feng-Long He
  • Publication number: 20150055805
    Abstract: A multi level charge pump circuit may be associated with at least two power supplies, and may provide at least four levels of positive and negative voltage. The multi level charge pump may include first and second fly capacitors, and first and second tank capacitors. A plurality of PMOS transistors and NMOS transistors may allow generation of two high voltage levels and two low voltage levels for the multi level charge pump, the low voltage levels being derived from a charging of the two fly capacitors in series. This multi level charge pump may be embodied in an audio device within a platform without a dedicated SMPS circuit.
    Type: Application
    Filed: August 18, 2014
    Publication date: February 26, 2015
    Inventor: Laurent Chevalier
  • Publication number: 20150055786
    Abstract: An alarm sounder, which incorporates a piezo-electric output transducer, can be silently monitored using a variable frequency square wave. An initial frequency, close to the upper limit of human hearing, is coupled to the sounder. The transducer draws very little current at this initial frequency. The frequency of the square wave is systematically reduced, and the current draw is continually monitored. A high current indicates a low impedance type of fault. A low current throughout the frequency range indicates a potential high frequency type of fault.
    Type: Application
    Filed: August 26, 2013
    Publication date: February 26, 2015
    Inventor: Michael BARSON
  • Patent number: 8965011
    Abstract: A method of attenuating an input signal to obtain an output signal is described. The method comprises receiving the input signal, attenuating the input signal with a gain factor to obtain the output signal, applying a filter having a frequency response with a frequency-dependent filter gain to at least one of a copy of the input signal and a copy of the output signal to obtain a filtered signal, the frequency-dependent filter gain being arranged to emphasize frequencies within a number N of predetermined frequency ranges, N>1; wherein the filter comprises a sequence of N sub-filters, each one of the N sub-filters having a frequency response adapted to emphasize frequencies within a corresponding one of the N predetermined frequency ranges; determining a signal strength of the filtered signal, and determining the gain factor from at least the signal strength.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: February 24, 2015
    Assignee: Dialog Semiconductor B.V.
    Inventor: Michiel Andre Helsloot
  • Patent number: 8963634
    Abstract: Techniques for sensing current delivered to a load by a differential output stage, e.g., in a Class D amplifier. In one aspect, voltages across sense resistors coupled in series with first and second branches of the differential output stage are low-passed filtered and digitized. The sense resistors may be coupled in series with the sources of transistors of the first and second branches, wherein the transistors are selectively switchable on and off by input voltage driving voltages. The input driving voltages may correspond to a ternary voltage waveform such that during a given phase, the two transistors coupled in series with the sense resistors may be turned off. Further aspects provide for the first and second branches having cascoded NMOS and/or PMOS transistors, and the sense resistors being provided between a pair of cascoded transistors.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: February 24, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Ankit Srivastava, Matthew D. Sienko, Meysam Azin, Xiaohong Quan, Peter J. Shah
  • Patent number: 8965010
    Abstract: An amplifier (50) for voice or audio signals, and particularly for headset applications, uses a low gm amplifier (54) for initially charging an output node (OUT) at the beginning of a power-on phase. After charging the output node, a main amplifier (56) is enabled to amplify the voice or audio signal. At power-down, a sample-and-hold circuit (58) drives an output transistor to discharge an AC coupling capacitor (20). Thus, spikes at the output node are eliminated and an external filtering capacitor is not needed.
    Type: Grant
    Filed: July 5, 2005
    Date of Patent: February 24, 2015
    Assignee: Texas Instruments Incorporated
    Inventors: Christian Sorace, Paolo Cusinato, Frederic Kubelec
  • Patent number: 8965774
    Abstract: For a media clip that includes audio content, a novel method for performing dynamic range compression of the audio content is presented. The method performs an analysis of the audio content. Based on the analysis of the audio content, the method generates a setting for an audio compressor that compresses the dynamic range of the audio content. The generated setting includes a set of audio compression parameters that include a noise gating threshold parameter (“noise gate”), a dynamic range compression threshold parameter (“threshold”), and a dynamic range compression ratio parameter (“ratio”).
    Type: Grant
    Filed: August 23, 2011
    Date of Patent: February 24, 2015
    Assignee: Apple Inc.
    Inventor: Aaron M. Eppolito
  • Patent number: 8958576
    Abstract: An amplifier including an input stage, an output stage, an adjustable bias current generator and a level detector. The input stage may receive and amplify or buffer an input signal. The input stage may be biased by a first bias current. The output stage may supply an output signal to an amplifier load. The output stage may be biased with a second bias current. The adjustable bias current generator may be operatively coupled to the input stage and the output stage to supply these with the first and second bias currents, respectively. The level detector may be operatively coupled to the input signal and the adjustable bias current generator to control the first and second bias currents depending upon the input signal. The adjustable bias current generator may adjust the respective levels of first and second bias currents in opposite directions. Disclosed is an electroacoustical transducer incorporating the amplifier.
    Type: Grant
    Filed: November 24, 2009
    Date of Patent: February 17, 2015
    Assignee: Invensense, Inc.
    Inventor: Jens Jørgen Gaarde Henriksen
  • Patent number: 8958575
    Abstract: A multi-mode amplifier with configurable DC-coupled or AC-coupled output is described. In one design, the multi-mode amplifier includes an amplifier and at least one DC level shifting circuit. The amplifier receives and amplifies an input signal and provides an output signal that is suitable for DC coupling to a load in a DC-coupled mode and for AC coupling to the load in an AC-coupled mode. The at least one DC level shifting circuit performs DC level shifting for at least one (e.g., input and/or output) common-mode voltage of the amplifier and is controlled based on whether the amplifier is operating in the DC-coupled or AC-coupled mode. The amplifier operates between VDD and VNEG supplies in the DC-coupled mode and between VDD and VSS supplies in the AC-coupled mode. The amplifier may include at least one gain stage, an internal DC level shifting circuit, and an output stage.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: February 17, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Uma Chilakapati, Anurag Pulincherry, Seyfollah Bazarjani
  • Patent number: 8958577
    Abstract: A system and method for modulating the sound pressure that is output from an audio transducer is disclosed. In one embodiment, the method includes receiving an audio signal and placing the audio signal across a voice coil of the transducer. In addition, a voltage is applied across a field coil of the transducer, the field coil being separate from the voice coil. And the voltage that is applied across the field coil is adjusted so as to modulate the sound pressure output from the audio transducer.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: February 17, 2015
    Assignee: FluxTone, Inc.
    Inventor: Stephen L. Carey
  • Patent number: 8953826
    Abstract: An application for present invention includes a television with a set of speaker outputs including at least a left speaker and a right speaker. On screen displays are used to properly configure the speakers and assure maximum audio quality from the television. In some embodiments, a cross-point switch connects the speakers attached to the television with the correct outputs of an internal amplifier.
    Type: Grant
    Filed: June 11, 2013
    Date of Patent: February 10, 2015
    Assignee: Vizio, Inc.
    Inventors: Kenneth Lowe, William Wang
  • Patent number: 8954177
    Abstract: A mechanism is provided for automatically controlling the operation of a media device based at least in part upon whether a portable presentation device coupled to the media device is currently being worn by a user. A portable presentation device may be any device that is meant to be worn by a user and that is capable of presenting media content to the user (e.g. earphones, headphones, goggles or faceplates with video/audio capability, etc.). With this mechanism, a user can affect the operation of the media device by simply putting on or taking off the portable presentation device. The user does not need to manually manipulate the controls of the media device. By automatically controlling the operation of the media device in this manner, use of the media device and the portable presentation device as a unit is made much simpler and more convenient.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: February 10, 2015
    Assignee: Apple Inc.
    Inventor: Christopher John Sanders
  • Publication number: 20150030183
    Abstract: Audio amplification may be improved by controlling an audio amplifier based on the audio signal being amplified. For example, when the audio signal level increases or decreases, a boost voltage provided to an audio amplifier by a boost converter may also be increased or decreased. In another example, when the audio signal level decrease below a certain level, the audio amplifier may be switched from amplifying the audio signal with a boost converter input to amplifying the audio signal with a low voltage input. Control of the audio amplifier may be implemented in a digital boost converter controller coupled to the boost converter and/or the audio amplifier.
    Type: Application
    Filed: February 18, 2014
    Publication date: January 29, 2015
    Applicant: CIRRUS LOGIC, INC.
    Inventors: Ullas Pazhayaveetil, Jeffrey May, Anu Chakravarty, Gautham Kamath, John Tucker, Christian Larsen
  • Publication number: 20150030184
    Abstract: An audio amplifier is provided with: an amplifier circuit; a power supply circuit that generates a plurality of power supply voltages; a power supply relay that selects one of the power supply voltages as the power supply voltage supplied to the amplifier circuit; a switching condition determiner that determines whether the switching condition of the power supply relay is satisfied; a silent section detector that detects a silent section of the audio signal which is equal to or greater than the operation time of the power supply relay; and a switching instruction unit for providing the power supply relay with an instruction for switching the power supply voltage during the silent section when the switching condition is satisfied and the silent section is detected.
    Type: Application
    Filed: February 6, 2013
    Publication date: January 29, 2015
    Inventor: Morito Yamada
  • Patent number: 8942391
    Abstract: A distortion compensation system minimizes distortion in an audio system by monitoring a supply voltage and adjusting a clipping threshold and/or compression knee. An adjustable gain circuit controls the gain of the audio signal according whether the audio signal exceeds a variable threshold. The variable threshold is adjusted within a threshold range based on the supply voltage. Distortion due to clipping of the audio signal is minimized while available power at any given time is maximized.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: January 27, 2015
    Assignee: Harman International Industries, Incorporated
    Inventor: Kenneth Carl Furge
  • Publication number: 20150016634
    Abstract: An impedance matched resonant circuit uses inductors coupling an audio source and a speaker array in order to reduce feedback reflection induced by an audio signal traveling from the audio source to the array of speakers. An RC circuit could also be coupled to the positive and negative terminals of the speaker array to reduce the slope differential of the audio signal at certain frequencies. The circuit can be packaged together in a single module with switches to activate and deactivate portions of the circuit to alter the effectiveness of the circuit depending upon need.
    Type: Application
    Filed: October 1, 2014
    Publication date: January 15, 2015
    Inventor: Wayne J. Powell
  • Patent number: 8934647
    Abstract: An audio device incorporates a first acoustic driver having a first direction of maximum acoustic radiation and a second acoustic driver having a second direction of maximum acoustic radiation, where the first and second directions of maximum acoustic radiation are not in parallel, and where the audio device employs the first acoustic driver or the second acoustic driver in acoustically outputting a sound of a predetermined range of frequencies in response to the orientation of the casing of the audio device relative to the direction of the force of gravity.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: January 13, 2015
    Assignee: Bose Corporation
    Inventors: John Joyce, Eric J. Freeman