US20170374456A1 - Minimizing startup transients in an audio playback path - Google Patents
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- US20170374456A1 US20170374456A1 US15/195,626 US201615195626A US2017374456A1 US 20170374456 A1 US20170374456 A1 US 20170374456A1 US 201615195626 A US201615195626 A US 201615195626A US 2017374456 A1 US2017374456 A1 US 2017374456A1
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/30—Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters
- H03F1/305—Modifications of amplifiers to reduce influence of variations of temperature or supply voltage or other physical parameters in case of switching on or off of a power supply
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/007—Protection circuits for transducers
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/34—Negative-feedback-circuit arrangements with or without positive feedback
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/181—Low-frequency amplifiers, e.g. audio preamplifiers
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/181—Low-frequency amplifiers, e.g. audio preamplifiers
- H03F3/183—Low-frequency amplifiers, e.g. audio preamplifiers with semiconductor devices only
- H03F3/187—Low-frequency amplifiers, e.g. audio preamplifiers with semiconductor devices only in integrated circuits
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/72—Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers
- H03G3/20—Automatic control
- H03G3/30—Automatic control in amplifiers having semiconductor devices
- H03G3/34—Muting amplifier when no signal is present or when only weak signals are present, or caused by the presence of noise signals, e.g. squelch systems
- H03G3/348—Muting in response to a mechanical action or to power supply variations, e.g. during tuning; Click removal circuits
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/66—Digital/analogue converters
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/03—Indexing scheme relating to amplifiers the amplifier being designed for audio applications
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/129—Indexing scheme relating to amplifiers there being a feedback over the complete amplifier
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- H—ELECTRICITY
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- H03F—AMPLIFIERS
- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/381—An active variable resistor, e.g. controlled transistor, being coupled in the output circuit of an amplifier to control the output
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- H03F2200/00—Indexing scheme relating to amplifiers
- H03F2200/408—Indexing scheme relating to amplifiers the output amplifying stage of an amplifier comprising three power stages
Definitions
- the present disclosure relates in general to circuits for audio devices, including without limitation personal audio devices such as wireless telephones and media players, and more specifically, to systems and methods for minimizing audible effects of electrical transients during powering on or startup of an audio playback pack.
- Personal audio devices including wireless telephones, such as mobile/cellular telephones, cordless telephones, mp3 players, and other consumer audio devices, are in widespread use.
- Such personal audio devices may include circuitry for driving a pair of headphones or one or more speakers.
- Such circuitry often includes a power amplifier for driving an audio output signal to headphones or speakers.
- startup electrical transients of the audio playback path may lead to audible artifacts (e.g., pops or clicks) perceptible to a listener of the personal audio device.
- audible artifacts e.g., pops or clicks
- one or more disadvantages and problems associated with existing audio signal paths may be reduced or eliminated.
- a method may be provided for powering up or down a playback path comprising a digital-to-analog converter (DAC) for generating a non-ground-centered analog intermediate voltage centered at a common-mode voltage and coupled to a driver for generating a ground-centered playback path output voltage at an output of the driver wherein the output of the driver is clamped via a finite impedance to a ground voltage.
- the method may include transitioning continuously or in a plurality of discrete steps the analog intermediate voltage from an initial voltage to the common-mode voltage such that the transitioning is substantially inaudible at the output of the driver.
- a method for operating an output clamp of an output driver stage of a playback path may include transitioning continuously or in a plurality of discrete steps an impedance of the output clamp in order to match an output offset of the output driver stage in order to minimize audio artifacts appearing at an output of the output driver stage.
- a playback path may include a digital-to-analog converter (DAC) for generating a non-ground-centered analog intermediate voltage centered at a common-mode voltage, a driver coupled to the DAC for generating a ground-centered playback path output voltage at an output of the driver, an output clamp for clamping the output of the driver to a ground voltage via a finite impedance, and circuitry configured to transition continuously or in a plurality of discrete steps the analog intermediate voltage from an initial voltage to the common-mode voltage such that the transition is substantially inaudible at the output of the driver.
- DAC digital-to-analog converter
- a playback path may include a driver for generating a ground-centered playback path output voltage at an output of the driver, an output clamp for clamping the output of the driver to a ground voltage via a finite impedance, and a controller for operating the output clamp by, each time the output clamp is activated or deactivated, transitioning continuously or in a plurality of discrete steps an impedance of the output clamp in order to match an output offset of the driver in order to minimize audio artifacts appearing at an output of the driver.
- FIG. 1 is an illustration of an example personal audio device, in accordance with embodiments of the present disclosure.
- FIG. 2 is a block diagram of selected components of an example audio integrated circuit of a personal audio device, in accordance with embodiments of the present disclosure.
- FIG. 1 is an illustration of an example personal audio device 1 , in accordance with embodiments of the present disclosure.
- FIG. 1 depicts personal audio device 1 coupled to a headset 3 in the form of a pair of earbud speakers 8 A and 8 B.
- Headset 3 depicted in FIG. 1 is merely an example, and it is understood that personal audio device 1 may be used in connection with a variety of audio transducers, including without limitation, headphones, earbuds, in-ear earphones, and external speakers.
- a plug 4 may provide for connection of headset 3 to an electrical terminal of personal audio device 1 .
- Personal audio device 1 may provide a display to a user and receive user input using a touch screen 2 , or alternatively, a standard liquid crystal display (LCD) may be combined with various buttons, sliders, and/or dials disposed on the face and/or sides of personal audio device 1 . As also shown in FIG. 1 , personal audio device 1 may include an audio integrated circuit (IC) 9 for generating an analog audio signal for transmission to headset 3 and/or another audio transducer.
- IC audio integrated circuit
- FIG. 2 is a block diagram of selected components of an example audio IC 9 of a personal audio device, in accordance with embodiments of the present disclosure.
- a microcontroller core 18 may supply a digital audio input signal DIG_IN to a digital-to-analog converter (DAC) 14 , which may convert the digital audio input signal to an intermediate analog signal Y IN .
- DAC digital-to-analog converter
- DAC 14 may supply intermediate analog signal Y IN to an amplifier 16 which may amplify or attenuate audio input signal Y IN in conformity with a gain to provide an audio output signal V OUT , which may operate a speaker, headphone transducer, a line level signal output, and/or other suitable output.
- Amplifier 16 may comprise multiple amplifier stages 22 , 24 , and 26 coupled in succession with one another and a plurality of resistors 28 such that the gain of amplifier 16 is set by the resistances of resistors 28 . As shown in FIG.
- amplifier 16 may include, due to non-idealities of amplifier 16 (e.g., temperature variations, process tolerances, device mismatch, passive mismatch, etc.), a slight inherent offset 29 from a desired ground or common mode voltage associated with amplifier stage 16 , which may affect signal output V OUT .
- amplifier 16 may include a switch 34 coupled between amplifier stage 24 and amplifier stage 26 .
- Such switch 34 may be deactivated (e.g., open, off, disabled, etc.) when the playback path implemented by audio IC 9 is powered down, and activated (e.g., closed, on, enabled, etc.) when the playback path is powered on.
- amplifier 16 may also be referred to as a “driver.”
- FIG. 2 also depicts an output clamp 30 having a finite variable resistor 32 coupled between the output of amplifier 16 and ground.
- a controller e.g., controller 20
- variable resistor 32 may have a low impedance, such that audio output voltage V OUT is forced to approximately ground voltage.
- a controller e.g., controller 20
- variable resistor 32 may have a high impedance (ideally infinite), such that audio output voltage V OUT may be driven by amplifier 16 .
- variable resistor 32 may be implemented using a plurality of parallel switches each having a finite impedance, such that an impedance of variable resistor 32 is controlled by selectively activating and deactivating individual switches.
- Controller 20 may comprise any system, device, or apparatus for controlling clamp 30 and the resistance of variable resistor 32 .
- one or more components of audio IC 9 may cause analog intermediate voltage V IN to transition continuously or in a plurality of discrete steps from an initial voltage (e.g., ground voltage) to a common-mode voltage of DAC 14 such that the transition is substantially inaudible at the output of amplifier 16 .
- an initial voltage e.g., ground voltage
- a common-mode voltage of DAC 14 such that the transition is substantially inaudible at the output of amplifier 16 .
- a level-shifting current may flow from the output of DAC 14 to the output node of amplifier 36 (e.g., via the network of resistors 28 ) and through clamp 30 .
- clamp 30 was an ideal clamp with zero impedance, such current would cause no change in voltage V OUT at the output node of amplifier 16 .
- clamp 30 no matter how well constructed or engineered, may have a finite impedance associated with it and when the level-shifting current flows through such impedance, a voltage step in output voltage V OUT may be created at the output.
- analog intermediate voltage V IN may be transitioned in a manner in which a sequence of voltage steps created at the output node of amplifier are sufficient to minimize or eliminate audible artifacts.
- such transition may be performed by microcontroller core 18 or another component of audio IC 9 forcing digital input signal DIG_IN to DAC 14 to a maximum (e.g., maximum positive or maximum negative value) such that analog intermediate voltage Y IN is initially set to the ground voltage when DAC 14 is powered on due to start-up of the playback path, and then microcontroller core 18 may transition digital input signal DIG_IN continuously or in a plurality of discrete steps such that analog intermediate voltage Y IN transitions from the initial voltage (e.g., ground voltage) to the common-mode voltage such that the transitioning is substantially inaudible at the output of amplifier 16 .
- a maximum e.g., maximum positive or maximum negative value
- microcontroller core 18 may transition digital input signal DIG_IN continuously or in a plurality of discrete steps such that analog intermediate voltage Y IN transitions from the initial voltage (e.g., ground voltage) to the common-mode voltage such that the transitioning is substantially inaudible at the output of amplifier 16 .
- variable current source 36 may be coupled to the output of DAC 14 and may be configured to increase the current output by such variable current source 36 continuously or in a plurality of discrete steps such that analog intermediate voltage Y IN transitions from the initial voltage (e.g., ground voltage) to the common-mode voltage such that the transitioning is substantially inaudible at the output of amplifier 16 .
- controller 20 may operate output clamp 30 by, each time the output clamp 30 is activated (e.g., impedance decreased to low impedance upon powering off of playback path) or deactivated (e.g., impedance decreased to low impedance upon powering on of playback path), transitioning continuously or in a plurality of discrete steps variable resistance 32 of output clamp 30 in order to match voltage offset 29 of amplifier 16 to the audio output signal V OUT in order to minimize audio artifacts appearing at the output of the amplifier 16 .
- one of stages 22 or 24 of amplifier 16 may in effect be configured as a comparator to compare analog output signal V OUT to voltage offset 29 .
- controller 20 may be configured to transition variable resistance 32 of output clamp 30 in order to match voltage offset 29 of amplifier 16 to the audio output signal V OUT such that when output clamp 30 is activated or deactivated, audio output signal V OUT experiences no substantial change.
- references in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, or component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative.
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Multimedia (AREA)
- Theoretical Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Amplifiers (AREA)
- Analogue/Digital Conversion (AREA)
Abstract
Description
- The present disclosure relates in general to circuits for audio devices, including without limitation personal audio devices such as wireless telephones and media players, and more specifically, to systems and methods for minimizing audible effects of electrical transients during powering on or startup of an audio playback pack.
- Personal audio devices, including wireless telephones, such as mobile/cellular telephones, cordless telephones, mp3 players, and other consumer audio devices, are in widespread use. Such personal audio devices may include circuitry for driving a pair of headphones or one or more speakers. Such circuitry often includes a power amplifier for driving an audio output signal to headphones or speakers.
- Using existing approaches, during startup of an audio playback path of a personal audio device, startup electrical transients of the audio playback path may lead to audible artifacts (e.g., pops or clicks) perceptible to a listener of the personal audio device.
- In accordance with the teachings of the present disclosure, one or more disadvantages and problems associated with existing audio signal paths may be reduced or eliminated.
- In accordance with embodiments of the present disclosure, a method may be provided for powering up or down a playback path comprising a digital-to-analog converter (DAC) for generating a non-ground-centered analog intermediate voltage centered at a common-mode voltage and coupled to a driver for generating a ground-centered playback path output voltage at an output of the driver wherein the output of the driver is clamped via a finite impedance to a ground voltage. The method may include transitioning continuously or in a plurality of discrete steps the analog intermediate voltage from an initial voltage to the common-mode voltage such that the transitioning is substantially inaudible at the output of the driver.
- In accordance with these and other embodiments of the present disclosure, a method for operating an output clamp of an output driver stage of a playback path may include transitioning continuously or in a plurality of discrete steps an impedance of the output clamp in order to match an output offset of the output driver stage in order to minimize audio artifacts appearing at an output of the output driver stage.
- In accordance with these and other embodiments of the present disclosure, a playback path may include a digital-to-analog converter (DAC) for generating a non-ground-centered analog intermediate voltage centered at a common-mode voltage, a driver coupled to the DAC for generating a ground-centered playback path output voltage at an output of the driver, an output clamp for clamping the output of the driver to a ground voltage via a finite impedance, and circuitry configured to transition continuously or in a plurality of discrete steps the analog intermediate voltage from an initial voltage to the common-mode voltage such that the transition is substantially inaudible at the output of the driver.
- In accordance with these and other embodiments of the present disclosure, a playback path may include a driver for generating a ground-centered playback path output voltage at an output of the driver, an output clamp for clamping the output of the driver to a ground voltage via a finite impedance, and a controller for operating the output clamp by, each time the output clamp is activated or deactivated, transitioning continuously or in a plurality of discrete steps an impedance of the output clamp in order to match an output offset of the driver in order to minimize audio artifacts appearing at an output of the driver.
- Technical advantages of the present disclosure may be readily apparent to one skilled in the art from the figures, description and claims included herein. The objects and advantages of the embodiments will be realized and achieved at least by the elements, features, and combinations particularly pointed out in the claims.
- It is to be understood that both the foregoing general description and the following detailed description are examples and explanatory and are not restrictive of the claims set forth in this disclosure.
- A more complete understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like reference numbers indicate like features, and wherein:
-
FIG. 1 is an illustration of an example personal audio device, in accordance with embodiments of the present disclosure; and -
FIG. 2 is a block diagram of selected components of an example audio integrated circuit of a personal audio device, in accordance with embodiments of the present disclosure. -
FIG. 1 is an illustration of an example personal audio device 1, in accordance with embodiments of the present disclosure.FIG. 1 depicts personal audio device 1 coupled to aheadset 3 in the form of a pair ofearbud speakers Headset 3 depicted inFIG. 1 is merely an example, and it is understood that personal audio device 1 may be used in connection with a variety of audio transducers, including without limitation, headphones, earbuds, in-ear earphones, and external speakers. A plug 4 may provide for connection ofheadset 3 to an electrical terminal of personal audio device 1. Personal audio device 1 may provide a display to a user and receive user input using atouch screen 2, or alternatively, a standard liquid crystal display (LCD) may be combined with various buttons, sliders, and/or dials disposed on the face and/or sides of personal audio device 1. As also shown inFIG. 1 , personal audio device 1 may include an audio integrated circuit (IC) 9 for generating an analog audio signal for transmission toheadset 3 and/or another audio transducer. -
FIG. 2 is a block diagram of selected components of anexample audio IC 9 of a personal audio device, in accordance with embodiments of the present disclosure. As shown inFIG. 2 , amicrocontroller core 18 may supply a digital audio input signal DIG_IN to a digital-to-analog converter (DAC) 14, which may convert the digital audio input signal to an intermediate analog signal YIN. -
DAC 14 may supply intermediate analog signal YIN to anamplifier 16 which may amplify or attenuate audio input signal YIN in conformity with a gain to provide an audio output signal VOUT, which may operate a speaker, headphone transducer, a line level signal output, and/or other suitable output.Amplifier 16 may comprisemultiple amplifier stages resistors 28 such that the gain ofamplifier 16 is set by the resistances ofresistors 28. As shown inFIG. 2 ,amplifier 16 may include, due to non-idealities of amplifier 16 (e.g., temperature variations, process tolerances, device mismatch, passive mismatch, etc.), a slightinherent offset 29 from a desired ground or common mode voltage associated withamplifier stage 16, which may affect signal output VOUT. As also shown inFIG. 2 ,amplifier 16 may include aswitch 34 coupled betweenamplifier stage 24 andamplifier stage 26.Such switch 34 may be deactivated (e.g., open, off, disabled, etc.) when the playback path implemented byaudio IC 9 is powered down, and activated (e.g., closed, on, enabled, etc.) when the playback path is powered on. In some instances,amplifier 16 may also be referred to as a “driver.” -
FIG. 2 also depicts anoutput clamp 30 having afinite variable resistor 32 coupled between the output ofamplifier 16 and ground. When the playback path implemented byaudio IC 9 is powered down, a controller (e.g., controller 20) may causevariable resistor 32 to have a low impedance, such that audio output voltage VOUT is forced to approximately ground voltage. When the playback path implemented byaudio IC 9 is powered on, a controller (e.g., controller 20) may causevariable resistor 32 to have a high impedance (ideally infinite), such that audio output voltage VOUT may be driven byamplifier 16. In some embodiments,variable resistor 32 may be implemented using a plurality of parallel switches each having a finite impedance, such that an impedance ofvariable resistor 32 is controlled by selectively activating and deactivating individual switches.Controller 20 may comprise any system, device, or apparatus for controllingclamp 30 and the resistance ofvariable resistor 32. - In operation, in order to reduce audio artifacts caused by electrical transients occurring at startup of the playback path implemented by
audio IC 9, one or more components ofaudio IC 9 may cause analog intermediate voltage VIN to transition continuously or in a plurality of discrete steps from an initial voltage (e.g., ground voltage) to a common-mode voltage ofDAC 14 such that the transition is substantially inaudible at the output ofamplifier 16. When the analog intermediate voltage VIN is transitioned to any non-zero value, a level-shifting current may flow from the output ofDAC 14 to the output node of amplifier 36 (e.g., via the network of resistors 28) and throughclamp 30. Ifclamp 30 was an ideal clamp with zero impedance, such current would cause no change in voltage VOUT at the output node ofamplifier 16. However,clamp 30, no matter how well constructed or engineered, may have a finite impedance associated with it and when the level-shifting current flows through such impedance, a voltage step in output voltage VOUT may be created at the output. However, in the present disclosure, analog intermediate voltage VIN may be transitioned in a manner in which a sequence of voltage steps created at the output node of amplifier are sufficient to minimize or eliminate audible artifacts. For example, in some embodiments, such transition may be performed bymicrocontroller core 18 or another component ofaudio IC 9 forcing digital input signal DIG_IN toDAC 14 to a maximum (e.g., maximum positive or maximum negative value) such that analog intermediate voltage YIN is initially set to the ground voltage whenDAC 14 is powered on due to start-up of the playback path, and thenmicrocontroller core 18 may transition digital input signal DIG_IN continuously or in a plurality of discrete steps such that analog intermediate voltage YIN transitions from the initial voltage (e.g., ground voltage) to the common-mode voltage such that the transitioning is substantially inaudible at the output ofamplifier 16. In other embodiments, a variable current source 36 (or a plurality of current sources in parallel with each other and DAC 14) may be coupled to the output ofDAC 14 and may be configured to increase the current output by such variablecurrent source 36 continuously or in a plurality of discrete steps such that analog intermediate voltage YIN transitions from the initial voltage (e.g., ground voltage) to the common-mode voltage such that the transitioning is substantially inaudible at the output ofamplifier 16. - In addition or alternatively, in operation,
controller 20 may operateoutput clamp 30 by, each time theoutput clamp 30 is activated (e.g., impedance decreased to low impedance upon powering off of playback path) or deactivated (e.g., impedance decreased to low impedance upon powering on of playback path), transitioning continuously or in a plurality of discretesteps variable resistance 32 ofoutput clamp 30 in order to matchvoltage offset 29 ofamplifier 16 to the audio output signal VOUT in order to minimize audio artifacts appearing at the output of theamplifier 16. In some embodiments, one ofstages FIG. 2 as stage 24) may in effect be configured as a comparator to compare analog output signal VOUT tovoltage offset 29. In other words, by sensing an output of one of the stages ofamplifier 16 other than thefinal output stage 26, the output ofsuch stage output clamp 30 has caused audio output signal VOUT to reach a voltage approximately equal tovoltage offset 29, andcontroller 20 may cease the transitioning upon occurrence of audio output signal VOUT reaching a voltage approximately equal tovoltage offset 29. In these and other embodiments,controller 20 may be configured to transitionvariable resistance 32 ofoutput clamp 30 in order to matchvoltage offset 29 ofamplifier 16 to the audio output signal VOUT such that whenoutput clamp 30 is activated or deactivated, audio output signal VOUT experiences no substantial change. - Although the various systems and methods described herein contemplate reduction of audio artifacts in audio paths of personal audio devices, the systems and methods herein may also apply to any other audio systems, including, without limitation, home audio systems, theaters, automotive audio systems, live performances, etc.
- This disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the exemplary embodiments herein that a person having ordinary skill in the art would comprehend. Similarly, where appropriate, the appended claims encompass all changes, substitutions, variations, alterations, and modifications to the exemplary embodiments herein that a person having ordinary skill in the art would comprehend. Moreover, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, or component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative.
- All examples and conditional language recited herein are intended for pedagogical objects to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are construed as being without limitation to such specifically recited examples and conditions. Although embodiments of the present inventions have been described in detail, it should be understood that various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the disclosure.
Claims (20)
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- 2016-06-30 GB GB1821043.5A patent/GB2565971B/en active Active
- 2016-06-30 WO PCT/US2016/040458 patent/WO2018004610A1/en active Application Filing
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Also Published As
Publication number | Publication date |
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US9854357B1 (en) | 2017-12-26 |
GB201821043D0 (en) | 2019-02-06 |
GB2565971A (en) | 2019-02-27 |
WO2018004610A1 (en) | 2018-01-04 |
GB2565971B (en) | 2022-02-23 |
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