Patent Publication Number: US-2007123314-A1

Title: Low power mode for a multiple function handheld device

Description:
CROSS REFERENCE TO RELATED PATENTS  
      This patent application relates to co-pending patent application entitled MULTIPLE FUNCTION HANDHELD DEVICE, having an attorney docket number of SIG000229.  
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
      NOT APPLICABLE  
     INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC  
      NOT APPLICABLE  
     BACKGROUND OF THE INVENTION  
      1. Technical Field of the Invention  
      This invention relates generally to handheld devices and more particularly to modes of a handheld device.  
      2. Description of Related Art  
      Integration of conventionally separate handheld devices into a single handheld device is current trend in the art. For instance, cellular telephones have been integrated with personal digital assistants (PDA), digital cameras, and walkie-talkie functionality. More recently, cellular telephones have been integrated with digital audio players (e.g., MP3 and/or WMA players). Such integration provides the user of a handheld device the convenience of carrying one device with the functionality of two or more devices.  
      While an integrated handheld device provides multiple functionalities, there are some instances and/or locations, where the user cannot or should not use one or more of the functionalities. For instance, current Federal Aviation Administration (FAA) prohibits the use of cellular telephones on airplanes in transit, but allows the use of other handheld devices (e.g., PDA, digital audio player). In such instances, to comply with FAA regulations, a cellular telephone with additional integrated functions (e.g., PDA, digital audio player) the entire handheld device must be powered down. Thus, the user is not able to use the approved functionality of the handheld device.  
      An ongoing design challenge with handheld devices is to reduce power consumption thereby increasing battery life (i.e., the duration for which a handheld device can operate properly without recharging or replacing its battery source). When the handheld device includes integration of multiple functionalities, reduction of power consumption is an even greater challenge. In some handheld devices, certain functions may be disabled based on available power.  
      Therefore, a need exists for a handheld device that provides greater flexibility of use and/or controlled power consumption. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)  
       FIG. 1  is an exploded view of a cellular telephone with digital audio and/or video in accordance with the present invention;  
       FIG. 2  is a schematic block diagram of a cellular telephone with digital audio in accordance with the present invention;  
       FIG. 3  is a schematic block diagram of a cellular telephone with a plurality of functional circuits in accordance with the present invention;  
       FIG. 4  is a schematic block diagram of a multiple function handheld device in accordance with the present invention;  
       FIG. 5  is a schematic block diagram of another embodiment of a multiple function handheld device in accordance with the present invention;  
       FIG. 6  is a schematic block diagram of yet another embodiment of a multiple function handheld device in accordance with the present invention;  
       FIG. 7  is a schematic block diagram of a still further embodiment of a multiple function handheld device in accordance with the present invention;  
       FIG. 8  is a schematic block diagram of yet another embodiment of a multiple function handheld device in accordance with the present invention;  
       FIG. 9  is a logic diagram of a method for enabling portions of a multiple function handheld device in accordance with the present invention;  
       FIG. 10  is a logic diagram of a method for enabling portions of a multiple function handheld device based on power states in accordance with the present invention; and  
       FIG. 11  is a logic diagram of a method for determining when a multiple function handheld device is in a 1st power state in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an exploded diagram of a cellular telephone  10  with digital audio and/or video functional circuitry. As shown, the cellular telephone  10  includes a rear housing  12 , a front housing  14 , and a printed circuit board  16 . The rear housing  12  may support a battery  38 . The front housing  14  may include a display  30 , a headphone jack  32 , a microphone  34 , a speaker  36  and an input control pad. The printed circuit board  16  may include one or more printed circuit boards that support a plurality of integrated circuits. Such integrated circuits may include a cellular phone radio frequency (RF) integrated circuit (IC)  18 , a cellular telephone baseband (BB) integrated circuit  20 , a digital audio integrated circuit  22 , memory integrated circuits  24 ,  26  and may further include a digital video integrated circuit  28 .  
      The cellular telephone  10 , in a wireless communication mode of operation, may be used to support wireless communications such as cellular telephone communications, walkie-talkie communications, and/or dispatch communications. The cellular telephone  10  may alternatively operate in a digital audio mode to playback and/or record digital audio files. Such digital audio files may be in an MP3 format, WMA format and/or any other proprietary and/or standardized digital audio format. If the cellular telephone  10  includes video processing functionality (e.g., as may be performed by IC  28 , or multiple ICs not shown), it may operate in a video mode to capture and/or play back still and/or motion video images. Such video images may be formatted in accordance with one or more video standards such as MPEG (motion picture expert group), JPEG (Joint Photographic Experts Group), etc.  
      The cellular telephone  10  may further include integrated circuits, and/or functionality within existing integrated circuits, to support a personal digital assistant (PDA) function. Such a personal digital assistant function allows task management, calendar management, contact list management, note management, et cetera. Accordingly, the cellular telephone  10  is a multiple function handheld device that enables a user to selectively utilize a variety of functional circuits (e.g., digital audio playback/record, digital video playback/record, PDA functions, and/or wireless communication functions).  
       FIG. 2  is a schematic block diagram of the cellular telephone  25  that includes digital audio functionality. In this embodiment, the cellular telephone  25  includes the cellular telephone RFIC  18 , the cellular telephone baseband IC  20 , the digital audio IC  22 , the display  30 , an I/O interface  58 , memory  56  (which may be included in one or more of integrated circuits  24  and  26 ), a plurality of multiplexers  60 - 68 , a mixing module  70 , the microphone  34 , the headphone jack  32 , and the speaker  36 . The cellular telephone RF IC  18  may include a direct IF conversion topology or a super heterodyne conversion technology. In general, the cellular telephone RFIC  18  includes a low noise amplifier  50 , a mixing module  48 , and a low pass filter  46  for-receiving RF signals and includes a low pass filter  44 , mixing module  42  and a power amplifier  40  for transmitting RF signals. The cellular telephone baseband IC  20  includes a wireless communication processing module  52 . The digital audio IC  22  includes a digital audio processing module  54 . In one embodiment, the digital audio processing IC may be an STMP 35xx and/or an STMP 36xx as produced and manufactured by SigmaTel, Inc.  
      The wireless communication processing module  52  and the digital audio processing module  54  may each be a single processing device or a plurality of processing devices. Such a processing device may be a microprocessor, micro-controller, digital signal processor, microcomputer, central processing unit, field programmable gate array, programmable logic device, state machine, logic circuitry, analog circuitry, digital circuitry, and/or any device that manipulates signals (analog and/or digital) based on operational instructions. Each processing module  53  and/or  54  may have associated therewith a memory element that may be a single memory device, a plurality of memory devices, and/or embedded circuitry of the processing module. Such a memory device may be a read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any device that stores digital information. Note that when the processing module  52  and/or  54  implements one or more of its functions via a state machine, analog circuitry, digital circuitry, and/or logic circuitry, the memory element storing the corresponding operational instructions may be. embedded within, or external to, the circuitry comprising the state machine, analog circuitry, digital circuitry, and/or logic circuitry. Further note that, the memory element stores, and the processing module.  52  and/ 54  executes, operational instructions corresponding to at least some of the steps and/or functions illustrated in  FIGS. 1-11 .  
      The cellular telephone  25  may be placed in a variety of different operating modes based on a mode selection. The mode selection may be received from the user via the I/O interface  58 , which may be a USB (universal serial bus) interface, an infrared interface, a keyboard, I 2 C interface, et cetera. The particular mode selection may be processed by the wireless communication processing module  52  and/or the digital audio processing module  54 . Alternatively, the cellular telephone  25  may receive an RF signal via the cellular telephone RF IC  18  indicating a particular mode of operation. For example, upon entering a hospital, an RF control signal may be broadcast in the lobby indicating that cellular telephone use is not allowed within the hospital. Upon receiving this RF signal, the cellular telephone automatically disables the wireless communication functionality of the cellular telephone while leaving the digital audio processing functionality in the state of operation specified by the user (e.g., enabled or disabled). Accordingly, the user may enable or disable the digital audio functionality of the cellular telephone with the wireless communication functionality disabled. Such a feature is also beneficial for air travel, where many governmental agencies (e.g., Federal Aviation Agency—FAA) prohibit the use of cellular telephones on an airplane, but allow the use of CD players and MP3 players  
      In addition to disabling the wireless communication function and enabling the digital audio processing functionality, the user may place the cellular telephone in a second mode where the digital audio functionality is disabled and the wireless communication functionality is enabled. Further, the user may place the cellular telephone in a third mode where both the wireless communication functionality and the digital audio processing functionality are enabled. Still further, the user may place the cellular telephone in a fourth mode where both the wireless communication processing functionality and the digital audio processing functionality are disabled. Such selective. enabling and disabling of circuit functionalities of the cellular telephone allows the user to maintain certain functionalities while disabling others, which, in some instances, allows the user to comply with particular regulations of the environment in which the user is located (e.g., on an airplane) and/or to reduce power consumption by disabling functional circuitry that the user does not desire to use.  
      When the digital audio processing functionality is enabled, the digital audio processing module  54  may function in a playback mode where it retrieves stored digital audio files from memory  56  and produces therefrom a monotone audio output  72  and/or a stereo audio output  74 . The audio outputs  72  and  74  may be in an analog format or a digital format. If the wireless communication processing functionality is disabled, the cellular telephone will provide the stereo audio output  74  to the headphone jack  32  via multiplexer  64  and  66  when a headphone is plugged into headphone jack  32 . If a headphone is not being used, multiplexers  64 ,  66  and  68  provide the monotone audio output  72  (which may be produced by summing the left and right channels of the stereo audio output) to speaker  36 . Note that when a headphone is plugged into headphone jack  32  multiplexer  68  provides a mute signal to speaker  36 .  
      In a record mode, the digital audio processing module  54  receives an audio input via microphone  34  and multiplexers  62  and  60 . The digital audio processing module  54  converts the audio signals into a digital audio file that may be stored in memory  56 . In this mode, the digital audio processing module  54  is functioning as a digital voice recorder.  
      When the wireless communication processing functionality is enabled and the digital audio processing functionality is disabled, the wireless communication processing module  52  processes incoming communications via the LNA  50 , mixing module  48  and low pass filter  46  of the cellular telephone RF IC  18  to produce analog signals. The analog signals are provided either to a headphone via the headphone jack  32  or to the speaker  36  via multiplexers  64 ,  66  and  68 . For outgoing communications, analog signals are received via microphone  34  and multiplexers  62  and  60 . The wireless communication processing module  52  converts the analog signals into baseband symbols, which are then converted into RF signals via the low pass filter  44 , mixing module  42  and power amplifier  40 .  
      In a mode when both the wireless communication processing functionality and digital audio processing functionality are enabled, the received wireless communication signals may be mixed via mixer  70  with the monotone audio output  72  of the digital audio processing module  54 . This allows for background music, to be played while a wireless communication is active. In one embodiment, the monotone audio output  72  may be scaled to a volume level such that it does not substantially interfere with the ongoing wireless communication.  
       FIG. 3  is a schematic block diagram of a cellular telephone  80  that includes a plurality of functional circuits. The functional circuits include, but are not limited to, digital audio processing, digital video processing, digital video capture, and/or personal digital assistant (PDA) functionality. In this embodiment, the cellular telephone  80  includes the cellular telephone RF IC  18 , the cellular telephone baseband IC  20 , the digital audio IC  22 , memory  56 , a digital image video capture module  84 , a digital video processing module  82 , the display  30 , the  10  interface  58 , a PDA processing module  85 , multiplexers  60 - 68  and  86 , the headphone jack  32 , the microphone  34 , and the speaker  36 . As with the embodiment of  FIG. 2 , the wireless communication processing module  52  may support cellular telephone communications (e.g., one to one), walkie talkie communications (e.g., one to many), and/or dispatch communications (e.g., many to one). In addition, the digital audio processing module  54  may support digital audio playback, digital audio record, file transfer, digital audio encode and digital audio decode. The audio input and output via microphone  34  and headphone jack  32  or speaker  36  function as previously described with reference to  FIG. 2 .  
      The digital image video capture module  84  may be a digital recorder that captures still images and/or motion video images. The digital representation of the image and/or motion video is provided to the digital video processing module  82 , which converts the received image and/or motion video into a corresponding digital video file, which may be formatted in accordance with MPEG, JPEG, a proprietary digital video image storage scheme and/or other standardized video digital image storage schemes. Accordingly, the digital video processing module  82  provides functionality for one or more of digital motion video playback, digital still image video playback, digital motion video record, digital still image record, digital video encoding, and/or digital video decoding.  
      The PDA processing module  85  enables the cellular telephone to provide the user with PDA functionality, which includes, but is not limited to, calendar management, task management, note management, and/or contact information management. The digital video processing module  82  and/or the PDA processing module  85  may be separate integrated circuits and/or combined with one or more of the wireless communication processing module  52  and the digital audio processing module  54 .  
      Multiplexer  86  selects a video output to be provided to display  30 . For example, in one mode, the multiplexer  86  may pass the video output from the digital video processing module  82  to display  30 . The video output may be in an analog or digital format depending on the type of display and may include still images and/or motion video. Alternatively, the multiplexer  86  may provide an output from the wireless communication processing module  52  indicating information relevant to a wireless communication. As yet another alternative, the multiplexer  86  may output information regarding a digital audio file record and/or playback. As yet another option, multiplexer  86  may output a PDA signal that corresponds to a particular PDA function. In either mode, the IO interface  58  provides a corresponding input to one or more of the processing modules  52 ,  54 ,  82 , and  85 . In this embodiment, the cellular telephone  80  includes a plurality of functional circuits (e.g., wireless communication functionality, digital audio processing functionality, digital video processing functionality, digital image capturing, and PDA functionality). Accordingly, the user may actively select one or more of the circuit functionalities to be active at any given time, or the selection may be an automatic function of the cellular telephone, to comply with particular regulations of the environment in which the user is located (e.g., on an airplane), and/or to conserve power.  
      In another embodiment, the cellular telephone via one or more of the processing modules and/or a control module (not shown in  FIG. 3 , but is shown in subsequent figures) monitors the battery voltage of the cellular telephone. Based on the power level of the battery, the processing module and/or control module enables and/or disables circuit functionality in accordance with a priority enablement ordering. For example, when the battery is fully charged, or is a new battery, the priority enablement ordering may allow all of the functional circuits to be activate. As the battery power level decreases, indicating that the battery life is shortening, certain functional circuits are disabled. When the battery power level is near exhausted, the priority enablement ordering may only enable the wireless communication functionality such that the cellular telephone may receive and/or initiate a wireless communication.  
      The battery power level may be determined in a variety of ways. For example, the battery voltage may be compared with a plurality of voltage thresholds. When the battery voltage compares favorably to a highest threshold, an indication is provided indicating that the battery power level is fully charged and/or the battery is new. As the voltage level drops, the battery voltage will compare unfavorably to more and more thresholds until it reaches the lowest battery threshold indicating that the cellular telephone should be placed in a low battery mode thus, disabling all but the most critical function(s). In one embodiment, the most critical function may be the use of the cellular telephone for emergency calls. In another embodiment, however, the user may select the functions that are to be deemed critical and establish the ordering of which functions are disabled based on the decreasing battery power.  
      In one example embodiment, the priority enablement ordering may be wireless communication processing as the highest priority, followed by PDA functionality, followed by digital audio processing, followed by digital video processing. Accordingly, as the battery voltage drops, the digital video processing will be first disabled, then the digital audio processing, then the PDA functionality.  
       FIG. 4  is a schematic block diagram of a multiple function handheld device  90  that includes the wireless communication processing module  52 , the digital audio processing module  54 , and a control module  92 . The control module  92  may be included within one or more of processing modules  52  and  54  or it may be a separate processing module.  
      The control module  92  is operably coupled to receive a mode select signal  93  and/or a battery voltage  95 . In one embodiment, the control module  92 , based on the mode select signal  93  enables or disables  98  processing module  52  and/or enables or disables  100  processing module  54 . For example, in a  1 st mode, the control module may disable the wireless communication processing module  52  while enabling the digital audio processing module  54 . While enabled, the digital audio processing module  54  converts digital audio files  96  into processed digital audio  102 , which may be an analog audio output or a digital audio output. In such a mode, the multiple function handheld  90  allows the user to be compliant with particular regulations of an environment (e.g., on an airplane where the use of cellular telephones is not permitted).  
      In another mode, the control module  92  may disable the audio processing module  54  and enable the wireless communication processing module  52 . While enabled, the wireless communication processing module  52  processes wireless communications inbound and outbound  94  into processed voice communications  104 . In another mode, the control module  92  may disable both processing modules  52  and  54 . In yet another mode, the control module  92  may enable both processing modules  52  and  54 .  
      The control module  92 , while monitoring the battery voltage  95  may selectively enable or disable processing modules  52  and  54  based on the monitored battery voltage. In one embodiment, when the battery voltage  95  compares unfavorably to a threshold voltage, the control module  92  establishes a 1st power state. In the 1st power state, the control module  92  disables at least a portion of the audio processing functionality of the digital audio processing module  54  while enabling at the wireless communication functionality of the wireless communication processing module  52 . If the battery voltage  95  compares favorably to the threshold voltage, the control module  92  establishes a 2nd power state. In the 2nd power state, the control module enables both processing modules  52  and  54 .  
       FIG. 5  is a schematic block diagram of another embodiment of a multiple function handheld device  110 . In this embodiment, the multiple function handheld device  110  includes the wireless communication processing module  52 , the digital audio processing module  54 , the digital video processing module  82 , and the control module  92 . In this embodiment, the control module  92  may activate one or more of the processing modules  52 ,  54  and  82  based on the mode select signal  93 .  
      In addition, the control module  92  may activate one or more of the processing modules  52 ,  54  and  82  based on the battery voltage  95 . For instance, when the battery voltage compares favorably to a 1st voltage threshold, the control module  92  may enable all three processing modules  52 ,  54  and  82 . When the battery voltage drops below the 1st threshold but is above a 2nd threshold, the control module may disable the video processing module  82 , while enabling the digital audio processing module  54  and the wireless communication processing module  52 . When the battery voltage  95  drops below a 2nd threshold but is above a 3rd threshold, the control module may enable the wireless communication processing module  52 , but disable the digital video processing module  82  and the digital audio processing module  54 . Note that when the digital video processing module  82  is enabled, it processes digital video  114  to produce processed digital video  116 . The digital video may be stored MPEG files and/or stored JPEG which are rendered into an analog or digital video output for subsequent display.  
       FIG. 6  is a schematic block diagram of yet another embodiment of a multiple function handheld device  120 . In this embodiment, the multiple function handheld device  120  includes the wireless communication processing module  52 , the digital audio processing module  54 , control module  92  and a mixing module  122 . In this embodiment, the wireless communication processing module  52 , while processing a wireless communication, may generate processed voice communications  104 , a ring tone  124 , an incoming call indication  126 , and/or call-on-hold data  130 . The call-on-hold data may correspond to playback of a digital audio file  96  for a call that is on hold.  
      In this embodiment, the mixing module  122  may mix the processed digital audio  102  with one or more of the processed voice communications  104 , ring tone  124  and/or incoming call indication  126 . The volume levels at which the signals are mixed to produce mixed signal  128  may be varied. In addition, the processed digital audio  102  may be faded out as an incoming call is indicated.  
      When the wireless communication processing module  52  is facilitating an active wireless communication and has placed another wireless communication on hold, the mixing module  102  may provide the processed voice communications  104  to the speaker and/or headphone jack while also providing the processed digital audio  102  to the wireless communication processing device  52 . The wireless communication processing device  52  provides the processed digital audio  102  for the wireless communication on hold as the call-on-hold data  130 . In this instance, while a 3rd party is on hold, it is receiving playback of a digital audio file from the multiple function handheld device  120 .  
       FIG. 7  is a schematic block diagram of yet another embodiment of a multiple function handheld device  140 . In this embodiment, the multiple function handheld device  140  includes an RF transceiver  145 , the digital audio processing module  54 , display  30 , I/O interface  58 ,.memory  56 , microphone  34 , headphone jack  32 , speaker  36 , and multiplexers  150  and  152 . The digital audio processing module  54  includes a digital audio encoder  142  and a digital audio decoder  144 . The RF transceiver  145  includes an RF transmit path which includes low pass filter  44 , mixer  42  and power amplifier  40  and a receive path that includes low noise amplifier  50 , mixer  48  and low pass filter  46 .  
      In this embodiment, the digital audio processing module  54  may process digital audio files stored in memory  56  and/or as a digital voice recorder as previously described. In addition, the digital audio processing module  54  may further function to provide the baseband processing of incoming and outgoing wireless communications.  
      For wireless communications, the audio signals received via microphone  34  are provided to the digital audio encoder  142 . The digital audio encoder  142  encodes the audio signals to produce outgoing baseband signals. The RF transceiver  145  converts the outgoing baseband signals into outgoing RF signals that are transmitted to a base station for relaying to another cellular telephone user, dispatch center, and/or other walkie talkie user. The RF transceiver  145  also receives inbound RF signals that are converted into inbound baseband signals. The digital audio decoder  144  converts the inbound baseband signals into a monotone audio signal  146  (or stereo signal) that is subsequently provided to the speaker  36  or headphone jack  32 .  
      In such an embodiment, the digital audio encoder  142  and digital audio decoder  144  may include a combination of wireless communication baseband processing and digital audio processing where common components are shared but function essentially separately. Alternatively, the digital audio encoding and digital audio decoding may be in accordance with a digital audio standard being supported by the multiple function handheld device wherein the baseband signals of the wireless communication function are at least partially encoded/decoded based on the digital audio standard. For example, the digital audio encoding  142  and digital audio decoding  144  may be done in accordance with a particular digital audio file format such as MP3, WMA, et cetera wherein the digital audio file format signals are converted into inbound and/or outbound baseband signals to support a wireless communication.  
       FIG. 8  is a schematic block diagram of yet another embodiment of a multiple function handheld device  160 . In this embodiment, the handheld device  160  includes the RF transceiver  145 , a baseband processing module  166 , memory  56 , audio processing module  54 , the microphone  34 , headphone jack  32 , speaker  36  and multiplexers  150 ,  192  and  194 . In this embodiment, the baseband processing module  166  processes inbound baseband signals  172  and outbound baseband signals  170  in accordance with the wireless communication protocol or protocols being supported by the handheld device  130 . Such a wireless communication protocol may be GSM, CDMA, et cetera.  
      The baseband processing module  166  functions to convert stored digital audio files  186 , which are stored in a format corresponding to a wireless communication protocol, into outbound digitized audio signals  188 . In this instance, the processing module  54  includes a digitizing audio output module  164  and digitizing audio input module  162 . The digitizing audio output module  164  converts the outbound digitized audio signals  188  into analog output signals  190  which may be provided to the headphone jack  32  or speaker  36  via multiplexers  192  and  194 . Alternatively, multiplexers  192  and  194  may provide the inbound communication data  174  from the baseband processing module  166  to headphone jack  32  or speaker  36 .  
      The digitizing audio input module  162  may provide audio signals  176 , via microphone  34 , as digitized audio signals  178  to the baseband processing module  166 . The baseband processing module  166  converts the digitized audio signals  178  into a digital audio file  180  that may be stored in memory  56 . Additionally, the digitizing audio input module  162  may pass inbound digitized audio signals  182  to the baseband processing module  166 . The baseband processing module  166  converts the inbound digitized audio signals  182  into a 2nd digital audio file  184 , which may be stored in memory  56 . The conversion of digitized audio signals  178  and/or  182  into digital audio files  180  or  184  may be done in accordance with the encoding performed by the baseband processing module  166  that it utilizes to encode outbound communication data  168  into outbound baseband signals  170 .  
       FIG. 9  is a logic diagram of a method for enabling functional circuits of a multiple function handheld device. The process begins at Step  200  where a determination is made as to whether the handheld device is in a 1st mode. If so, the process proceeds to Step  202  where at least a portion of the digital audio functionality is enabled and the wireless communication functionality is disabled. In one embodiment, the digital audio functionality includes at least one of digital audio playback, digital audio record, file transfer, digital audio encode and digital audio decode. In an embodiment, the wireless communication functionality includes at least one of cellular telephone communication processing, walkie talkie communication processing and dispatch communication processing. In another embodiment, the handheld device may include digital video functionality that may be enabled when the device is in the 1st mode. In one embodiment, the digital video functionality includes at least one of digital motion video playback, digital still image video playback, digital motion video record, digital still image record, digital video encode and digital video decode.  
      The handheld device may be placed in the 1st mode by detecting selection of the 1st mode by interpreting a menu selection, interpreting a button activation via the keyboard, and/or interpreting proximity based wireless communication information. For example, the proximity based wireless communication information may be a wireless communication indicating that the handheld device should be placed in the 1st mode.  
      If the device is not in the 1st mode, the process proceeds to Step  202  to determine whether it is in a 2nd mode. If so, the at least a portion of the digital audio functionality is disabled while the wireless communication functionality is enabled.  
      If the device is not in the 2nd mode, a determination is made as to whether it is in a 3rd mode. If the device is in a 3rd mode, the digital audio functionality and wireless communication functionality are enabled.  
      If the device is not in the 3rd mode, a determination is made as to whether it is in a 4th mode. If the device is in a 4th mode, the process proceeds to Step  214  where the digital audio functionality and wireless communication functionality are disabled.  
       FIG. 10  is a logic diagram of a method for power conservation of a multiple function handheld device. The process begins at Step  220  where a determination is made as to whether the device is in a 1st power state. The determination of the 1st power state will be described in greater detail with reference to the logic diagram of  FIG. 11 . When the device is in a 1st power state, the process proceeds to Step  222  where at least a portion of the digital audio functionality is disabled and the wireless communication functionality is enabled.  
      If the device is not in the 1st power state, the process proceeds to Step  224  where, in a 2nd power state, the digital audio functionality and wireless communication functionality are enabled.  
       FIG. 11  is a logic diagram for determining whether the handheld device is in a 1st power state. The process begins at Step  226  where a battery voltage is monitored. The process then proceeds to Step  228  where the battery voltage is compared with a threshold voltage. The process then proceeds to Step  230  where a determination is made as to whether the comparison of Step  228  is favorable. If not, the process proceeds to Step  232  where an indication that the device is in the 1st power state is made. If the comparison is favorable, the process proceeds to Step  234  where an indication that the device is in the 2nd power state is made.  
      As one of ordinary skill in the art will appreciate, the term “substantially” or “approximately”, as may be used herein, provides an industry-accepted tolerance to its corresponding term and/or relativity between items. Such an industry-accepted tolerance ranges from less than one percent to twenty percent and corresponds to, but is not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, and/or thermal noise. Such relativity between items ranges from a difference of a few percent to magnitude differences. As one of ordinary skill in the art will further appreciate, the term “operably coupled”, as may be used herein, includes direct coupling and indirect coupling via another component, element, circuit, or module where, for indirect coupling, the intervening component, element, circuit, or module does not modify the information of a signal but may adjust its current level, voltage level, and/or power level. As one of ordinary skill in the art will also appreciate, inferred coupling (i.e., where one element is coupled to another element by inference) includes direct and indirect coupling between two elements in the same manner as “operably coupled”. As one of ordinary skill in the art will further appreciate, the term “operably associated with”, as may be used herein, includes direct and/or indirect coupling of separate components and/or one component being embedded within another component. As one of ordinary skill in the art will still further appreciate, the term “compares favorably”, as may be used herein, indicates that a comparison between two or more elements, items, signals, etc., provides a desired relationship. For example, when the desired relationship is that signal  1  has a greater magnitude than signal  2 , a favorable comparison may be achieved when the magnitude of signal  1  is greater than that of signal  2  or when the magnitude of signal  2  is less than that of signal  1 .  
      The preceding discussion has presented a variety of method and apparatus for enabling and/or power conservation of multiple functions of a multiple function handheld device. As one of ordinary skill in the art will appreciate, other embodiments of the present invention may be derived from the teachings contained herein without deviating from the scope of the claims.