Method and system for switched battery charging and loading in a stereo headset

Methods and systems for wireless communication are disclosed and may include controlling a loading and/or a charging of a battery source in each earpiece of the wireless stereo headset. The loading control may include switching between the battery sources powering the headset. A remaining power level may be monitored for each of the battery sources. Both earpieces in the headset may be powered utilizing one or both of the battery sources. One of the earpieces in the headset may be powered utilizing one of the battery sources. A total usage time may be stored for each of the battery sources. The loading and charging of the battery sources may be controlled by equalizing the total usage time for each of the battery sources. The earpieces in the headset may be coupled via a tether line, or may be coupled wirelessly.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

FIELD OF THE INVENTION

Certain embodiments of the invention relate to wireless communication. More specifically, certain embodiments of the invention relate to a method and system for switched battery charging and loading in a stereo headset.

BACKGROUND OF THE INVENTION

Headphones were originally utilized for personal enjoyment of music without distracting other people in the vicinity of the music source. Headphones may comprise circumaural, earphones, and canal phones. Circumaural headphones cover the ears and are rather large, more attuned for home audio applications as compared to use with portable audio devices. Earphones are typically used in portable audio device applications, with cassette tape, compact disc and MP3 players, for example. The application of earphones later extended into cellular phone applications, typically as a single earpiece, as the danger of operating motor vehicles while utilizing a cellular phone was established.

With the development of wireless technology, wireless headphones have become more and more prevalent. Bluetooth headsets and/or earpieces have expanded significantly in usage as more cellular phone users have discovered the ease of use with hands-free operation, not only in automotive applications, but in any application where hands-free operation is preferred.

BRIEF SUMMARY OF THE INVENTION

A system and/or method for switched battery charging and loading in a stereo headset, substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims.

DETAILED DESCRIPTION OF THE INVENTION

Certain aspects of the invention may be found in a method and system for switched battery charging and loading in a stereo headset. Exemplary aspects of the invention may comprise controlling a loading and/or a charging of a battery source in each earpiece of the wireless stereo headset. The loading control may comprise switching between the battery sources powering the headset. A remaining power level may be monitored for each of the battery sources. Both earpieces in the headset may be powered utilizing one or both of the battery sources. One of the earpieces in the headset may be powered utilizing one of the battery sources. A total usage time may be stored for each of the battery sources. The loading and charging of the battery sources may be controlled by equalizing the total usage time for each of the battery sources. The earpieces in the headset may be coupled via a tether line, or may be coupled wirelessly.

FIG. 1is a block diagram of an exemplary wireless headset, in accordance with an embodiment of the invention. Referring toFIG. 1, there is shown a wireless headset100comprising ear buds, or ear pieces101A and101B and a tether wire105. The tether wire105may provide an electrical connection between the two ear pieces101A and101B for audio and/or control signals and/or supply voltage. The ear pieces101A and101B may be described further with respect toFIG. 2. There is also shown a charging port103, a charger107, a charger connector109and a wireless device111. In another embodiment of the invention, the ear pieces may be supported by a rigid structure as opposed to the tether wire105. In yet another embodiment of the invention, ear pieces101A and101B may not be physically connected and may only communicate wirelessly, by Bluetooth, for example.

The ear pieces101A and101B may also comprise one or more circuits and one or more batteries for controlling the powering of the wireless headset100, which may be located internal to the wireless headset100, as described with respect toFIG. 2. The power control may comprise determining which battery may be utilized at a given time, and also the charging routine to be followed to optimize power usage and/or battery charging, and also to optimize battery lifetime.

The charger107may comprise suitable circuitry, logic and/or code that may be enabled to charge the batteries in the wireless headset100. The charger connector109may be utilized to couple the charger107to the wireless headset100at the charging port103.

The wireless headset100may comprise power handling capability that may be utilized to optimize the charging and loading of the one or more batteries in each of the ear pieces101A and101B. The power handling and charging control may be controlled by circuitry in one ear piece that controls power handling and charging in the other earpiece via the tether wire105and/or Bluetooth signals. In another embodiment of the invention, the power handling circuitry may be entirely within the earpiece101A, which may then control the use and charging of one or more batteries in the earpiece101B via the tether wire105and/or Bluetooth signals. The wireless device111may comprise suitable circuitry, logic and/or code that may enable wireless communication between the user of the headset100and other wireless devices and users. The wireless device may comprise a cellular phone, or a handheld wireless communication and/or entertainment device, for example.

In operation, the wireless headset100may be powered by batteries internal to each of the ear pieces101A and101B in the wireless headset100. The wireless headset100may be enabled to playback audio signals received wirelessly from sources such as the wireless device111, for example. In instances when the battery voltage in one of the ear pieces101A and101B may drop below a threshold value required to power the wireless headset100, the wireless headset100may switch to a battery in the other ear piece101A or101B. The loading of the batteries may be optimized as per the requirements of the particular type of batteries used. For example, in instances where lithium batteries may be used, each battery may be drained as far as possible while still allowing operation of the wireless headset100, before switching over to another battery.

Similarly, the batteries may be charged as per the requirements of the particular type of batteries used. For example, in instances where lithium batteries may be used, each battery may be charged completely during charging before switching to another battery. In addition, the batteries may be in operation in both ear pieces at the same time, as in stereo music playback mode, for example, or may switch to only one battery and one ear piece101A or101B in operation, such as during a monaural (mono) voice call. In this manner, a battery usage versus device performance optimization may be defined as per current battery levels and/or user preference.

FIG. 2is a block diagram illustrating an exemplary ear piece schematic, in accordance with an embodiment of the invention. Referring toFIG. 2, there is shown the ear pieces101A and101B and the tether wire105. The tether wire105and the charging port103may be as described with respect toFIG. 1. The ear piece101A may comprise a speaker201A, a microphone203A, a battery205A, a BT radio207, an antenna209and a battery control circuit211. The earpiece101B may comprise a speaker201B, a microphone203B, a battery205B, a battery switch213, a processor215and a memory217.

The speakers201A and201B may comprise suitable circuitry, logic and/or code for converting electrical signals generated by the BT radio207and/or the microphones203A and203B into audio signals. The microphones203A and203B may comprise suitable circuitry, logic and/or code for converting received audio signals into electrical signals that may be transmitted by the BT radio207to the wireless device111, described with respect toFIG. 1.

The batteries205A and205B may each comprise one or more batteries for powering the headset100. One or more batteries may be incorporated into each earpiece101A and101B, such that the earpieces101A and101B may operate independently, or in a dependent mode where the one or more battery from one ear piece may provide power for both ear pieces101A and101B. The battery205A may be coupled to the battery control circuit211and the battery205B may be coupled to the battery switch213.

The BT radio207may comprise suitable circuitry, logic and/or code for communicating wirelessly with BT devices, such as the wireless device111, for example, described with respect toFIG. 1. The BT radio207may enable communication of signals received from the microphones203A and/or203B via the processor215to the wireless device111via the antenna209. Similarly, the BT radio207may be enabled to communicate wireless signals received from the wireless device111to the speakers201A and/or201B. In another embodiment of the invention, the earpiece101B may also comprise a BT radio, such as the BT radio207, such that audio and/or control signals may communicated without the need of a tether wire.

The antenna209may comprise suitable circuitry, logic and/or code that may enable transmission and/or reception of wireless signals. The antenna209may be communicatively coupled to the BT radio207and may be configured to operate in the Bluetooth frequency spectrum, for example.

The battery control circuit211may comprise suitable circuitry, logic and/or code that may enable controlling the power usage of the batteries205A and205B. The battery control circuit211may enable sensing of the remaining power levels in the batteries205A and205B for determining which battery may be utilized to power the ear pieces101A and101B at any given time. In addition, the battery control circuit211may determine which battery205A or205B may be charged first when the headset100may be coupled to the charger107, described with respect toFIG. 1.

The battery switch213may comprise suitable circuitry, logic and/or code that may enable switching the battery205B in and out of operation and may be controlled by the battery control circuit211. In this manner, one or both of the batteries205A and205B may be utilized to power the earpieces101A and101B.

The processor215may comprise suitable circuitry, logic and/or code that may enable control of the earpieces101A and101B. The processor215may control the battery control circuit211, the BT radio207, and any other component that may require processing capability. The processor215may be enabled to generate baseband signals from signals received from the microphone such that they may be transmitted by the BT radio207. The processor215may be located in the earpiece101B as shown inFIG. 2, or may be located in the earpiece101A. In another embodiment of the invention, the processor215may comprise two separate processors, with one processor located in each earpiece101A and101B.

The memory217may comprise suitable circuitry, logic and/or code that may enable storage of data for the processor215. The memory217may be enabled to store usage times for the batteries205A and205B, so that the battery control circuit211may equalize the battery charging and loading over time.

In operation, the ear pieces101A and101B may be enabled to communicate audio signals to the speakers201A and/or201B from the BT radio207and to communicate signals from the microphones203A and/or203B to the BT radio207for transmission to an external device, such as the wireless device111, described with respect toFIG. 1.

The battery control circuit211may sense the power levels remaining in the batteries205A and205B, and control which battery may be utilized to supply power for the ear pieces101A and101B. In an embodiment of the invention, the battery control circuit211may enable both batteries205A and205B to operate the ear pieces101A and101B, such as for stereo music playback, for example, where the power levels of both batteries may be sufficient. In instances where a battery voltage of one of the batteries, battery205A, for example, may be reduced to near the minimum voltage needed to power the ear pieces101A and/or101B, the battery control circuit211may switch over to the other battery, the battery205B in this example.

The battery control circuit211may also control the charging characteristics of the batteries205A and205B. The battery control circuit211may alternate charging and loading such that the usage of the batteries may be essentially equal over time. For example, in instances where the ear pieces101A and101B may be powered by the battery205A for a period of time such that the voltage on the battery205A may be reduced, and a charger, such as the charger107may be coupled to the earpiece101A via the charge port103, the battery205A may be charged. Subsequently, the battery control circuit211may switch over to the battery205B to be utilized as the primary power source to ensure uniform usage of the batteries205A and205B and to allow for a recharge period if necessary, as opposed to always using one battery first and the other battery as a backup.

The processor215may control various operations of the components in the earpieces101A and101A, and may comprise a baseband processor for processing of signals to be transmitted by the BT radio207. Additionally, the processor215may control the battery control circuit211via loading and charging algorithms configured for optimum lifetime of a particular type of battery utilized, lithium, or nickel-metal hydride, for example. The processor215may utilize the memory217for storing data generated in the operation of the earpieces101A and101B. The memory217may also be utilized for storing algorithms utilized to control the battery control circuit211.

In an embodiment of the invention, the processor215and the battery control circuit may enable one or more battery “fuel gauges” that may indicate the remaining charge level in the batteries205A and/or205B. The remaining charge level may be utilized to determine which battery or batteries may be utilized for a given application. The fuel gauges may comprise a visual indicator on the earpieces101A and/or101B, with a number of segments or LEDs, wherein the number of segments or LEDs illuminated may correspond to a charge level. In another embodiment of the invention, the fuel gauges may comprise a numerical indicator on the display of the earpiece101A and/or101B that may correspond to the level of charge in the batteries.

In another embodiment of the invention, the earpieces101A and101B may each comprise a BT radio, such as the BT radio207so that the earpieces may not require the tether105for coupling. In this embodiment, a battery control circuit may be utilized in each earpiece to control the battery usage. In this manner, battery control commands may be transmitted and received by BT radios in the earpieces101A and101B. For example, for a mono voice call, one of the earpieces, such as the earpiece101B may be idled while the other earpiece101A may be utilized to take a call.

FIG. 3is a block diagram illustrating an exemplary power control circuit, in accordance with an embodiment of the invention. Referring toFIG. 3, there is shown a power control circuit300comprising a charger circuit301, switch circuits303and305, the batteries205A and205B, a capacitor307, a voltage regulator block309, a latch311and a system block313. There is also shown a bus voltage (Vbus)315. The batteries205A and205B may be as described with respect toFIG. 2.

The charger circuit301may comprise suitable circuitry, logic and/or code that may enable charging of the batteries205A and205B. The charger301may receive as an input the voltage Vbus315which may be supplied by an external power source, such as the charger107, described with respect toFIG. 1. The charger may be coupled to the switch circuits303and305and the capacitor307.

The switch circuits303and305may comprise suitable circuitry, logic and/or code that may enable switching between power sources, such as the batteries205A and205B and the Vbus315. The switch circuit303may be coupled to the batteries205A and205B, the latch311, the charger301, the capacitor307and the switch circuit305, and may be utilized to switch between the batteries205A and205B. The switch circuit305may be coupled to the Vbus315, the charger301, the switch circuit303and the voltage regulator block309, and may enable switching between the batteries205A and/or205B and the Vbus315for powering the voltage regulator block309. The switch circuit303may be controlled by the latch311.

The capacitor307may be coupled across an input to the switch303B and ground, and may enable storage of charge for reducing fluctuations in the voltage supplied to the voltage regulator block309in instances of switching between sources, such as the Vbus315and the batteries205A and205B.

The voltage regulator block309may comprise suitable circuitry, logic and/or code that may enable providing a constant voltage to the system313, nearly independent of the input voltage to the voltage regulator block309. The voltage regulator block309may comprise low drop out voltage regulators that may enable an output voltage minimally reduced from the input voltage.

The latch311may comprise suitable circuitry, logic and/or code that may enable controlling the switch circuit303. The latch311may receive an input signal from the system313and generate an output signal that may be utilized to activate the switch circuit303. The latch311may also receive as an input the bus voltage, Vbus315, such that the switch circuit303may be enabled even when the voltages of the batteries205A and205B may be too low for normal operation.

The system313may comprise the remaining circuitry in the earpieces101A and101B, such as the BT radio207, the speakers201A and201B, the microphones203A and203B, the processor215and other circuitry required for operation of the headset100.

In operation, the power control circuit300may provide power for the operation of the system313. The switch circuit303may be utilized to select one or both of the batteries205A and205B to supply a voltage to the voltage regulator block309via the switch circuit305. In instances where a charger may be coupled to the power control circuit via a supply voltage, Vbus315, the charger301may be enabled to charge one of the batteries205A and205B. The supply voltage Vbus315may also be communicated to the voltage regulator block309via the switch circuit305.

The system313may generate an output signal, via the processor215, for example, activating the latch311to set the switch circuit303to the desired battery, so that battery205A and/or205B may be coupled to the switch circuit305via the switch circuit303. Algorithms may be utilized to control the loading and charging of the batteries205A and205B to optimize the lifetimes of the batteries. This may be accomplished by equalizing the usage time of each battery205A and205B. For example, in instances where the battery205A may be utilized and allowed to drain most of the charge, and where a charger may subsequently be coupled to the wireless headset100, the battery205A may be charged, and the battery205B may be utilized next to power the wireless headset100to equalize the usage of the batteries. The algorithms may be optimized for a particular type of battery used, and may depend on whether the battery type lasts longer when allowed to completely drain before charging, and whether a recharge state may be required after charging, for example.

FIG. 4is a flow diagram illustrating an exemplary dual battery charging and loading process, in accordance with an embodiment of the invention. Referring toFIG. 4, in step403, after start step401, the battery voltages may be checked. In step405, if the voltages may be low, the exemplary steps may proceed to step407. If in step407a charger may be coupled to the headset, the process may proceed to step409, where the first battery may be charged, followed by step411where the second battery may be charged. If, in step407, the battery voltages are low and no charger may be present, the headset may shut down in step419, followed by end step421.

If, in step405, the battery voltages may be suitable for operation of the headset, the exemplary steps may proceed to step413. If, in step413, if both batteries may be needed for a particular mode of operation, the exemplary steps may proceed to step415where the headset may powered by both batteries, and then proceed to step403, to repeat. If both batteries may not be required in step413, the battery with lower overall usage may be utilized to power the headset in step417before proceeding to step403to repeat the process.

In an exemplary embodiment of the invention, a method and system are disclosed for switched battery charging and loading in a stereo headset100and may comprise controlling a loading and/or a charging of a battery source205A and205B in each earpiece101A and101B of the wireless stereo headset100. The loading control may comprise switching between the battery sources205A and205B powering the wireless stereo headset100. A remaining power level may be monitored for each of the battery sources205A and205B. Both earpieces101A and101B in the wireless stereo headset100may be powered utilizing one or both of the battery sources205A and205B. One of the earpieces101A or101B in the wireless stereo headset100may be powered utilizing one of the battery sources205A or205B. A total usage time may be stored for each of the battery sources205A and205B. The loading and charging of the battery sources205A and205B may be controlled by equalizing the total usage time for each of the battery sources205A and205B. The earpieces in the wireless stereo headset100may be coupled via a tether line105, or may be coupled wirelessly.

Certain embodiments of the invention may comprise a machine-readable storage having stored thereon, a computer program having at least one code section for wireless communication, the at least one code section being executable by a machine for causing the machine to perform one or more of the steps described herein.

Accordingly, aspects of the invention may be realized in hardware, software, firmware or a combination thereof. The invention may be realized in a centralized fashion in at least one computer system or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system or other apparatus adapted for carrying out the methods described herein is suited. A typical combination of hardware, software and firmware may be a general-purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein.