System and method for adjusting the audio volume of a charging case
A charging case for a pair of wireless earphones, the charging case comprising: a housing having a peripheral wall that defines a shell and one or more audio openings formed through the peripheral wall; a frame insert coupled to the housing and extending into the shell, the frame insert having one or more insert walls that define first and second pockets sized and shaped to accept first and second wireless earphones, respectively; wherein the one or more insert walls cooperate with the housing peripheral wall to define a interior cavity within the charging case; a lid coupled to the housing and operable between a closed position in which the lid covers the first and second pockets and an open position in which the first and second pockets are exposed; a rechargeable battery disposed within the interior cavity; a speaker disposed within the interior cavity and aligned to emit sound through the one or more openings; and circuitry coupled to the battery and the speaker and configured to: initiate playing an audio asset on the speaker at a first gain level; while continuing to play the audio asset, increasing the gain level of the speaker from the first gain level to a final gain level by repeating a sequence of measuring a system load on the battery and increasing the gain level of the speaker until the measured system load reaches a threshold level; after the measured system load reaches the threshold level, setting the gain level of the speaker at the final gain level and continuing playing the audio asset with the gain set at the final gain level.
1 . A charging case for a pair of wireless earphones, the charging case comprising:
a housing having a peripheral wall that defines a shell and one or more audio openings formed through the peripheral wall;
a frame insert coupled to the housing and extending into the shell, the frame insert having one or more insert walls that define first and second pockets sized and shaped to accept first and second wireless earphones, respectively; wherein the one or more insert walls cooperate with the housing peripheral wall to define a interior cavity within the charging case;
a lid coupled to the housing and operable between a closed position in which the lid covers the first and second pockets and an open position in which the first and second pockets are exposed;
a rechargeable battery disposed within the interior cavity;
a speaker disposed within the interior cavity and aligned to emit sound through the one or more openings; and
circuitry coupled to the rechargeable battery and the speaker and configured to:
initiate playing an audio asset on the speaker at a first gain level;
while continuing to play the audio asset, increase a gain level of the speaker from the first gain level to a final gain level by repeating a sequence of: (i) measuring a system load on the rechargeable battery and (ii) increase the gain level of the speaker, until the measured system load reaches a threshold level; and
after the measured system load reaches the threshold level, set the gain level of the speaker at the final gain level and continue playing the audio asset with the gain set at the final gain level.
2 . The charging case set forth in claim 1 wherein measuring the system load on the rechargeable battery comprises determining a voltage level provided by the rechargeable battery and wherein the circuitry determines if the measured system load reaches the threshold level by comparing the voltage provided by the rechargeable battery to a threshold voltage level.
3 . The charging case set forth in claim 1 wherein measuring the system load on the rechargeable battery comprises determining a current level provided by the battery and wherein the circuitry determines if the measured system load reaches the threshold level by comparing the current level provided by the rechargeable battery to a threshold current level.
4 . The charging case set forth in claim 1 wherein the circuitry comprises wireless communication circuitry operable to receive a lost mode command from a host device and a controller operable to respond to the lost mode command by playing the audio asset on the speaker.
5 . The charging case set forth in claim 1 wherein the circuitry comprises an amplifier having an output coupled to the speaker and a microcontroller having an serial audio interface coupled to the amplifier.
6 . The charging case set forth in claim 1 wherein the circuitry comprises a controller and a power management circuit configured to provide a battery under voltage lock out (UVLO) that initiates a reset of the controller if the voltage provided by the battery drops below a threshold voltage level.
7 . The charging case set forth in claim 6 wherein the threshold voltage level is stored in the controller, and wherein the circuitry further comprises:
an audio clamping circuit comprising a comparator having a first input coupled to receive the threshold voltage level from the controller and a second input coupled to a voltage level of the battery.
8 . The charging case set forth in claim 1 wherein the circuitry comprises a controller and a power management circuit configured to provide a battery overcurrent protection (OCP) feature that initiates a reset of the controller if a current level delivered by the rechargeable battery to the speaker raises above a threshold current level.
9 . The charging case set forth in claim 8 wherein the threshold current level is stored in the controller, and wherein the circuitry further comprises:
an amplifier coupled at an output to the speaker; and
an audio clamping circuit comprising a comparator having a first input coupled to receive the threshold current level from the controller and a second input coupled to the output of the amplifier.
10 . The charging case set forth in claim 1 further comprising a memory that stores the audio asset.
11 . The charging case set forth in claim 10 wherein the circuitry comprises wireless communication circuitry operable to receive a lost mode command from a host device and a controller operable to respond to the lost mode command by playing the audio asset on the speaker.
12 . The charging case set forth in claim 11 wherein the memory is an external memory that stores a plurality of audio assets and the controller is operable to select one of the plurality of audio assets from the external memory to load into a memory of the controller.
13 . The charging case set forth in claim 1 wherein:
the circuitry is configured to store a plurality of audio assets;
the step of initiate playing an audio asset on the speaker at a first gain level plays a first audio asset in the plurality of assets in response to the charging case receiving a first command instruction; and
the circuitry is further configured to play a second audio asset, different than the first audio asset in response to receiving a second command instruction, different than the first command instruction.
14 . The charging case set forth in claim 13 wherein the circuitry is further configured to, when playing the second audio asset, set the gain of the speaker to a level that is determined based on an environmental condition external to the charging case.
15 . The charging case set forth in claim 14 wherein the environmental condition external to the charging case is one of: an ambient volume, a location of the charging case or a time of day.
16 . The charging case set forth in claim 1 , wherein the circuitry coupled to the rechargeable battery and the speaker is configured to set the initial gain level to a value below a maximum, and the sequence of increasing and measuring gain is performed prior to the circuitry detecting any system depletion or unsafe condition.
17 . The charging case set forth in claim 16 , wherein increasing the gain level of the speaker comprises incrementally increasing the gain in discrete steps and, after each step, measuring the system load before determining whether to further increase the gain.
18 . The charging case set forth in claim 17 , wherein the circuitry coupled to the rechargeable battery and the speaker is configured such that the gain level is not decreased during playback unless the measured system load exceeds a safety threshold, and wherein the maximum gain level is empirically determined for each playback session.
19 . The charging case set forth in claim 16 wherein the circuitry coupled to the rechargeable battery and the speaker is further configured to, after the gain level is set to the final gain level, maintaining the gain at that value for the remainder of the audio asset playback, unless a system load threshold is exceeded.
20 . The charging case set forth in claim 1 wherein measuring of system load and increasing of gain are performed by the circuitry automatically and continuously during an initial portion of playback of the audio asset, and wherein the final gain level is determined empirically based on real-time measurements of the rechargeable battery load.
21 . A storage case for a portable electronic device, the storage case comprising:
a housing defining a device storage area;
a lid coupled to the housing and operable between a closed position in which the lid covers the device storage area and an open position in which the device storage area first and second pockets are exposed;
a rechargeable battery;
a speaker; and
circuitry coupled to the rechargeable battery and the speaker and configured to:
initiate playing an audio asset on the speaker at a first gain level;
while continuing to play the audio asset, increase a gain level of the speaker from the first gain level to a final gain level by repeating a sequence of measuring a system load on the rechargeable battery and increasing the gain level of the speaker until the measured system load reaches a threshold level; and
after the measured system load reaches the threshold level, set the gain level of the speaker at the final gain level and continue playing the audio asset with the gain set at the final gain level.
22 . The storage case for a portable electronic device set forth in claim 21 wherein the storage case is configured to store first and second wireless earphones.
23 . The storage case for a portable electronic device set forth in claim 22 wherein the housing comprises a peripheral wall that defines a shell and includes one or more audio openings formed through the peripheral wall, and wherein the storage case further comprises a frame insert, coupled to the housing, and extending into the shell, the frame insert having one or more insert walls that define first and second pockets sized and shaped to accept first and second wireless earphones, respectively.
24 . An electronic device comprising:
a controller;
a rechargeable battery;
a speaker; and
circuitry coupled to the rechargeable battery and the speaker and configured to:
initiate playing an audio asset on the speaker at a first gain level;
while continuing to play the audio asset, increase a gain level of the speaker from the first gain level to a final gain level by repeating a sequence of measuring a system load on the rechargeable battery and increasing the gain level of the speaker until the measured system load reaches a threshold level; and
after the measured system load reaches the threshold level, set the gain level of the speaker at the final gain level and continue playing the audio asset with the gain set at the final gain level.
25 . The electronic device set forth in claim 24 wherein the electronic device is a storage case for a pair of wireless earphones.