# US 9,520,850 B2 · Power supplies > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,850 B2 - Document ID: US9520850B2 - Status: Granted - Kind: B2 - Application number: 14/488,919 - Filed: 2014-09-17 - Published: 2015-01-01 - Granted: 2016-12-13 - Earliest claimed: 2007-06-11 - Assignees: Sonos, Inc. - Applicants: Sonos, Inc. - Inventors: James F. Lazar; Mark Polomski - Web page: https://patentgrep.com/patent/US9520850B2 ## CPC - H03F 3/183: with semiconductor devices only - H03F 1/0222: {by using a signal derived from the input signal} - H03F 1/305: {in case of switching on or off of a power supply} - H03F 3/21: with semiconductor devices only {(H03F3/245 takes precedence)} - H03G 3/10: having semiconductor devices - H03G 3/301: {the gain being continuously variable} - H04R 27/00: Public address systems (circuits for preventing acoustic reaction H04R3/02; circuits for distributing signals to loudspeakers H04R3/12; {monitoring or testing arrangements for public address systems H04R29/007}; amplifiers H03F) - H04R 29/001: {for loudspeakers (H04R29/007 takes precedence)} - H03F 2200/03: the amplifier being designed for audio applications - H03F 2200/507: A switch being used for switching on or off a supply or supplying circuit in an IC-block amplifier circuit - H04R 2420/03: Connection circuits to selectively connect loudspeakers or headphones to amplifiers - H03F: AMPLIFIERS - H03G: CONTROL OF AMPLIFICATION - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) ## Abstract Techniques for providing multiple power supplies in electronic devices are disclosed. According to one aspect of the present invention, an appropriate power supply is provided only to accommodate a volume setting. In other words, there are at least two power supplies, one with a low voltage and the other with a high voltage. The high voltage power supply is only applied when there is a need to accommodate a volume setting. Thus the power consumption of the amplifiers is well controlled. As a result, the designs of the device and heat dissipation therein can be simplified and lowered in cost. ## Claims ### Claim 1 An audio player comprising: an audio amplifier; at least first and second supply voltages to energize the audio amplifier; a controller to detect a volume for play of an audio track and determine an associated supply voltage such that, at any time, only one of the first and second supply voltages is selected to energize the audio amplifier in response to the detected volume, wherein the controller is to determine an associated supply voltage based on a configurable parameter to tune a transition point between the first and second supply voltages based on speaker impedance. ### Claim 2 (depends on 1) The audio player of claim 1, wherein the controller is to detect a volume and determine an associated supply voltage based at least in part on a power profile generated from a digital file associated with the audio track. ### Claim 3 (depends on 2) The audio player of claim 2, wherein the power profile is to be dynamically generated via a buffered digital file. ### Claim 4 (depends on 1) The audio player of claim 1, wherein the configurable parameter is to be determined from at least one of a setting and a measurement. ### Claim 5 (depends on 1) The audio player of claim 1, wherein the first and second supply voltages are to be provided respectively by first and second power supplies. ### Claim 6 (depends on 1) The audio player claim 1, wherein the first and second supply voltages are to be provided by a single power supply. ### Claim 7 (depends on 1) The audio player of claim 1, wherein the first supply voltage is coupled to the audio amplifier via a switching mechanism, the switching mechanism to be turned on to couple the first supply voltage to the amplifier when the second supply voltage is disconnected so that the audio amplifier is to be energized by the first supply voltage, the switching mechanism to be turned off to couple the second supply voltage to the amplifier when the second supply voltage is applied so that the audio amplifier is to be energized by the second supply voltage. ### Claim 8 (depends on 1) The audio player of claim 1, wherein the second supply voltage is to be higher than the first supply voltage. ### Claim 9 (depends on 8) The audio player of claim 8, wherein the second supply voltage is to be applied onto the audio amplifier via a damping circuit designed to gradually rise from a level of the first supply voltage to a level of the second supply voltage. ### Claim 10 (depends on 9) The audio player of claim 9, wherein a time period to rise from the level of the first supply voltage to the level of the second supply voltage is adjustable. ### Claim 11 (depends on 1) The audio player of claim 1, wherein the controller is a circuit designed to detect the volume setting and configured to determine which one of the voltages is to be applied. ### Claim 12 (depends on 1) The audio player of claim 1, wherein the controller is configured to execute a software module to determine which one of the voltages is to be applied. ### Claim 13 (depends on 1) The audio player of claim 1, further comprising a damping circuit which reduces audible noise produced by the audio player when the controller switches between the first supply voltage and the second supply voltage. ### Claim 14 (depends on 1) The audio player of claim 1, wherein the speaker impedance is a minimum speaker impedance of the speaker for a range of frequencies output by the speaker. ### Claim 15 A non-transitory tangible computer-readable storage medium including a set of instructions for execution by a processor, the set of instructions, when executed, to implement a method to control supply voltage provided to an amplifier in a playback device, the method comprising: detect a volume setting for play of an audio track by an electronic audio player; determine, using a controller, an associated supply voltage for play of the audio track based on the volume setting and available power supply voltages; and facilitate selection of one of a first supply voltage and a second supply voltage such that, at any time, only one of the first and second supply voltages is selected to energize an audio amplifier of the electronic audio player in response to the detected volume to play the audio track, wherein the controller is to determine an associated supply voltage based on a configurable parameter to tune a transition point between the first and second supply voltages based on speaker impedance. ### Claim 16 (depends on 15) The non-transitory tangible computer-readable storage medium of claim 15, wherein the controller is to detect a volume and determine an associated supply voltage based at least in part on a power profile generated from a digital file associated with the audio track. ### Claim 17 (depends on 16) The non-transitory tangible computer-readable storage medium of claim 16, wherein the power profile is to be dynamically generated via a buffered digital file. ### Claim 18 (depends on 15) The non-transitory tangible computer-readable storage medium of claim 15, wherein the configurable parameter is to be determined from at least one of a setting and a measurement. ### Claim 19 (depends on 15) The non-transitory tangible computer-readable storage medium of claim 15, wherein the first and second supply voltages are to be provided respectively by first and second power supplies. ### Claim 20 (depends on 15) The non-transitory tangible computer-readable storage medium claim 15, wherein the first and second supply voltages are to be provided by a single power supply. ### Claim 21 (depends on 15) The non-transitory tangible computer-readable storage medium of claim 15, wherein the first supply voltage is coupled to the audio amplifier via a switching mechanism, the switching mechanism to be turned on to couple the first supply voltage to the amplifier when the second supply voltage is disconnected so that the audio amplifier is to be energized by the first supply voltage, the switching mechanism to be turned off to couple the second supply voltage to the amplifier when the second supply voltage is applied so that the audio amplifier is to be energized by the second supply voltage.