JP2015188141A - Portable terminal device and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To postpone the time when a built-in battery runs out when a remaining amount of the battery is decreasing in the middle of audio output in a portable terminal device having a film speaker serving as a capacitive load.SOLUTION: A portable terminal device comprises: a measurement part operable to repeatedly measure a remaining amount of electric power accumulated by a built-in battery; and a low-pass filter part which cuts off a radio frequency band of audio signals to be input to a film speaker according to the remaining amount of electric power measured by the measurement part so that the cut-off frequency when the remaining amount is under a predetermined amount is lower than the cut-off frequency when the remaining amount is over the predetermined amount.

Description

  The present invention relates to a portable terminal including a film speaker that behaves as a capacitive load.

A piezoelectric speaker using a piezoelectric element (see, for example, Patent Document 1) does not require a magnet and a coil required for an electromagnetic speaker, and is suitable for realizing a reduction in thickness and weight. Among them, a film speaker constituted by a resin film and a thin film piezoelectric element is particularly suitable for realizing a thin shape.
For this reason, some portable terminals for which a reduction in thickness is desired include a film speaker.

Film speakers behave as capacitive loads. That is, there is a characteristic that the impedance becomes lower as the frequency of the input signal becomes higher. Therefore, when a relatively high frequency band signal is input to the film speaker, a relatively large amount of current flows through the film speaker, and a relatively large amount of power is consumed.
Generally, since a portable terminal operates using limited power stored in a built-in battery, it is not preferable that relatively large power is consumed by a film speaker.

JP 2004-221742 A

In general, there is a demand for a portable terminal to postpone the time when the battery runs out when the remaining amount of the built-in battery decreases.
However, the portable terminal cannot meet this demand.
Accordingly, there is a need for a portable terminal equipped with a film speaker that can postpone the time when the battery runs out when the remaining battery level of the built-in battery is reduced when outputting sound.

  In order to solve the above problems, a mobile terminal according to one embodiment of the present invention is a mobile terminal that operates using power stored in a built-in battery, and includes a storage unit that stores an audio signal, and the storage A low-pass filter section that cuts a high-frequency band at the time of reproduction of an audio signal stored by the section, and a film that acts as a capacitive load that outputs sound to the outside based on the audio signal whose high-frequency band is cut by the low-pass filter section A speaker and a measurement unit that measures the remaining amount of electric power stored in the battery, wherein the low-pass filter unit has a predetermined amount corresponding to the remaining amount of electric power measured by the measurement unit. The cut-off frequency in the case where the remaining amount is lower than the cut-off frequency in the case where the remaining amount is larger than the predetermined amount. And performing cutting frequency band.

  The portable terminal according to one embodiment of the present invention can postpone the time when the battery runs out when the remaining battery of the built-in battery is reduced when outputting sound.

(A) The perspective view of the portable terminal 100 seen from the front side, (b) The perspective view of the portable terminal 100 seen from the back side (A) Front view of film speaker 200, (b) Cross section of film speaker 200 The figure which shows the frequency characteristic of the electric current which flows into the film speaker 200 when an alternating current signal is added to the film speaker 200 An exploded perspective view of a part of the mobile terminal 100 The block diagram which shows the circuit structure of the portable terminal 100 The block diagram which shows the function structure of the cut-off frequency control part 600 Data structure diagram of the sound source table 700 Schematic diagram showing a playback music designation screen 800 Data structure diagram of playback table 900 Data configuration diagram of the notification table 1000 Cut-off frequency control process flowchart The block diagram which shows the circuit structure of the portable terminal of a 1st modification. Flowchart of cut-off frequency control process of first modification Flowchart of cut-off frequency control process of second modification The block diagram which shows the function structure of the cut-off frequency control part 1500 Flowchart 1 of cut-off frequency control processing of the third modification 1 Flowchart 2 of the cut-off frequency control process of the third modification 2 The block diagram which shows the circuit structure of the portable terminal of a 4th modification. The block diagram which shows the function structure of the cut-off frequency control part 1900 Flowchart of cut-off frequency control process of fourth modification

<Embodiment>
<Overview>
Here, as an example of the portable terminal according to the present invention, a film speaker is provided, and when the battery remaining in the built-in battery is larger than a predetermined amount (for example, 15%), the first frequency band (for example, 10 KHz or more). The audio signal with the frequency band cut is used as an input signal to the film speaker, and the second frequency band including the first frequency band (for example, a frequency band of 5 KHz or more, for example) when the remaining battery capacity is less than a predetermined amount. A portable terminal that uses an audio signal from which a) is cut as an input signal to the film speaker will be described.

Hereinafter, the details of the portable terminal will be described with reference to the drawings.
<Configuration>
FIG. 1A is a perspective view showing an external appearance of the mobile terminal 100 viewed from the front side, and FIG. 1B is a perspective view showing an external appearance of the mobile terminal 100 viewed from the back side.
As shown in FIGS. 1A and 1B, the mobile terminal 100 is a so-called smartphone having a substantially rectangular parallelepiped shape, and the operation surface of the touch panel 110 is arranged on the front main surface, and the receiver hole 120. The microphone hole 130 is opened, and the first speaker hole group 140 and the second speaker hole group 150 are opened on the back main plane.

2A is a front view of the film speaker 200 built in the portable terminal 100, and FIG. 2B is a cross-sectional view of the film speaker 200. FIG.
As shown in the figure, the film speaker 200 is arranged such that a thin film-like piezoelectric element 220 is superimposed on the upper surface of a resin film 210, and the upper surface of the resin film 210 and the piezoelectric element 220 is covered with a resin coding agent 230. It is coded and surrounded by a frame 240.

When a signal voltage is applied to the piezoelectric element 220, the film speaker 200 generates distortion in the piezoelectric element 220, and the piezoelectric element 220 and the resin film 210 vibrate, and outputs sound corresponding to the applied signal voltage. To do. The film speaker 200 behaves as a capacitive load with respect to the applied signal voltage.
FIG. 3 shows a film speaker in the case where the frequency of the applied AC signal is changed while the voltage of the AC signal applied to the film speaker 200 is kept constant, that is, the sound pressure level of the output sound is kept constant. 2 is a graph showing a current flowing through 200.

In the figure, the horizontal axis is the frequency of the AC signal input to the film speaker 200 and is a logarithmic axis, and the vertical axis is the current flowing through the film speaker 200 and is the real axis.
As shown in the figure, in the film speaker 200, the current that flows increases as the frequency of the input signal increases under the condition that the applied voltage is kept constant.

FIG. 4 is an exploded perspective view of a part of the mobile terminal 100 showing a state in which the film speaker 200 is built in the mobile terminal 100.
As shown in the figure, the portable terminal 100 incorporates a film speaker 200a for outputting right audio and a film speaker 200b for outputting left audio in order to support stereo audio output. Yes.

In the figure, a housing lower portion 400 is a part of the housing of the mobile terminal 100, and the front main surface is removed from the housing of the mobile terminal 100.
The speaker holder 410 is a structure for fixing the film speaker 200a and the film speaker 200b, and is fitted into the housing lower part 400 and fixed to the housing lower part 400.

The film speaker 200a and the film speaker 200b are fixed to the speaker holder 410 by bonding the portion of the frame 240 to the speaker fixing portion 430a and the speaker fixing portion 430b, respectively.
In the speaker holder 410, a speaker hole 440a and a speaker hole 440b are opened in the central portion of the speaker fixing portion 430a and the central portion of the speaker fixing portion 430b, respectively.

  In a state where the speaker holder 410 is fixed to the housing lower part 400, the speaker hole 440a and the speaker hole 440b are respectively positioned to face the first speaker hole group 140 and the second speaker hole group 150. . Accordingly, the sound output from the film speaker 200a propagates to the outside of the mobile terminal 100 through the speaker hole 440a and the first speaker hole group 140, and the sound output from the film speaker 200b is transmitted to the speaker hole 440b. It propagates through the second speaker hole group 150 to the outside of the portable terminal 100.

FIG. 5 is a block diagram illustrating a circuit configuration of the mobile terminal 100.
As shown in the figure, the mobile terminal 100 includes a CPU (Central Processing Unit) 500, an antenna 505, a communication LSI (Large Scale Integration) 510, a touch panel controller 515, a touch panel 110, and a sound source storage 520. SD card reader 525, memory 530, receiver 535, microphone 540, timer 545, battery remaining amount measuring device 550, battery 555, decoder 560, first amplifier 565, and second amplifier 570 The film speaker 200a and the film speaker 200b are configured.

The antenna 505 is connected to the communication LSI 510 and used for communication performed by the communication LSI 510, for example, a monopole antenna made of a metal foil film.
Communication LSI 510 is connected to antenna 505 and CPU 500 and is controlled by CPU 500. And it has the function to communicate with an external base station.
The touch panel 110 is configured by overlaying a transparent touch pad on the display surface of the liquid crystal display, is connected to the touch panel controller 515, and is controlled by the touch panel controller 515. And it has the operation reception function which receives the contact operation of the user who uses the portable terminal 100, and the display function which displays an image.

  Touch panel controller 515 is connected to touch panel 110 and CPU 500 and is controlled by CPU 500. Then, a display control function for displaying an image based on an image signal sent from the CPU 500 on the touch panel 110 and a contact operation performed by the user using the portable terminal 100 using the touch panel 110 are converted into an electrical signal by the CPU 500. Contact operation conversion function to be sent to

  The sound source storage 520 is a data storage device connected to the CPU 500 and has a function of storing sound source data of audio output from the mobile terminal 100. The sound source data stored in the sound source storage 520 includes, for example, stereo audio data for music encoded in accordance with the MP3 (MPEG Audio Layer-3) standard, and the music title, genre name, and artist name for the music. Header data consisting of As an example, the sound source storage 520 is realized by a flash memory.

  The SD card reader 525 is connected to the CPU 500 and controlled by the CPU 500. And it has the mounting function which mounts | wears with an SD card so that attachment or detachment, and the read-out function which reads the sound source data of the audio | voice which the portable terminal 100 outputs from the mounted SD card. The sound source data stored in the SD card attached to the SD card reader 525 is data in the same format as the sound source data stored in the sound source storage 520.

The memory 530 is connected to the CPU 500 and stores a program that defines the operation of the CPU 500 and data used by the CPU 500. For example, the memory 530 is realized by a RAM (Random Access Memory), a ROM (Read Only Memory), and a flash memory.
The receiver 535 is connected to the CPU 500 and controlled by the CPU 500. And it has the function which converts the electric signal sent from CPU500 into a sound, and outputs the converted sound to the exterior of the portable terminal 100 through the receiver hole 120 (refer FIG. 1 (A)).

Microphone 540 is connected to CPU 500 and controlled by CPU 500. And it has the function which converts the audio | voice input from the portable terminal 100 exterior through the microphone hole 130 (refer FIG. 1 (A)) into an electrical signal, and sends the converted electrical signal to CPU500.
The battery 555 is connected to the battery remaining amount measuring device 550 and supplies power to the electronic components constituting the mobile terminal 100. The battery 555 is, for example, a secondary battery that can be repeatedly charged by a charger (not shown) that can be attached to and detached from the mobile terminal 100.

The battery remaining amount measuring device 550 is connected to the battery 555 and the CPU 500 and is controlled by the CPU 500. The battery 555 has a function of measuring the remaining amount of power stored in the battery 555. The battery remaining amount measuring device 550 outputs, as an example, the measured remaining amount of power as a percentage with respect to the amount of power stored during full charge.
The decoder 560 is connected to the first amplifier 565, the second amplifier 570, and the CPU 500, and is controlled by the CPU 500. Then, the encoded stereo audio data sent from the CPU 500 is decoded, and an audio signal for the right speaker (hereinafter referred to as “right audio signal”) and an audio signal for the left speaker (hereinafter referred to as “right audio signal”). The left audio signal is transmitted to the first amplifier 565, and the generated left audio signal is transmitted to the second amplifier 570.

Here, the encoded stereo audio data sent from the CPU 500 is included in the sound source data read from the sound source storage 520 or the SD card attached to the SD card reader 525.
The first amplifier 565 is connected to the decoder 560 and the film speaker 200a, amplifies the right audio signal sent from the decoder 560, and sends it to the film speaker 200a.

The second amplifier 570 is connected to the decoder 560 and the film speaker 200b, amplifies the left audio signal sent from the decoder 560, and sends it to the film speaker 200b.
The CPU 500 includes a communication LSI 510, a touch panel controller 515, a sound source storage 520, an SD card reader 525, a memory 530, a receiver 535, a microphone 540, a timer 545, a battery remaining amount measuring device 550, and a decoder 560. And connected to. And the following smart phone control functions and a cutoff frequency control function are implement | achieved by running the program memorize | stored in the memory 530.

The smartphone control function is a function equivalent to a general function as a smartphone that a conventional smartphone has in the mobile terminal 100 by controlling a circuit connected to the CPU 500 by the CPU 500 that executes a program, for example, a call This function realizes a function, an Internet site browsing function, a mail transmission / reception function, a standby function, a voice reproduction function, and the like.
The cut-off frequency control function means that a CPU 500 that executes a program controls a circuit connected to the CPU 500 to cause the mobile terminal 100 to execute a cut-off frequency control process that is a characteristic operation of the mobile terminal 100. At the time of reproduction, when the remaining amount of the battery 555 is larger than a predetermined amount (for example, 15%), an audio signal in which the first frequency band (for example, a frequency band of 10 KHz or more) is cut is sent to the film speakers 200a and 200b. This is a function of inputting an audio signal from which the second frequency band (for example, a frequency band of 5 KHz or more) has been cut to the film speakers 200a and 200b when the remaining battery 555 has a predetermined amount or less.

The cut-off frequency control process will be described in detail later with reference to a flowchart in the item <cut-off frequency control process>.
The configuration of the mobile terminal 100 having the above circuit configuration will be described below from the functional aspect. Here, among the functional blocks constituting the mobile terminal 100, the description will focus on the cutoff frequency control unit 600, which is a functional block that implements a cutoff frequency control process that is a characteristic operation performed by the mobile terminal 100.

FIG. 6 is a block diagram illustrating a functional configuration of the cutoff frequency control unit 600.
As shown in the figure, the cut-off frequency control unit 600 includes a control unit 610, a predetermined amount storage unit 615, a user operation reception unit 620, a notification instruction reception unit 625, a remaining amount measurement unit 630, and a reproduction. Table storage unit 635, notification table storage unit 640, sound source storage unit 645, sound source table storage unit 650, sound source reading unit 655, decoding unit 660, buffer unit 665, and constant variable low-pass filter unit 670 Composed.

The sound source storage unit 645 is connected to the sound source reading unit 655 and the sound source table storage unit 650, and is realized by a sound source storage 520, an SD card reader 525, and an SD card attached to the SD card reader 525. And it has a function which memorize | stores the sound source data of the audio | voice which the portable terminal 100 outputs.
The sound source table storage unit 650 is connected to the sound source storage unit 645 and the control unit 610 and is realized by the CPU 500 and the memory 530. And it has the function to memorize | store and update the sound source table 700 which shows the information about the sound source data memorize | stored in the sound source memory | storage part 645. FIG.

FIG. 7 is a data configuration diagram of the sound source table 700 stored by the sound source table storage unit 650.
As shown in the figure, the sound source table 700 includes an ID 710, a song name 720, an artist name 730, a file name 740, a storage location 750, a directory for each sound source data stored in the sound source storage unit 645. 760 and genre 770 are associated with each other.

ID 710 is an identifier for identifying sound source data.
The song name 720 is a song name of a song included in the sound source data.
The artist name 730 is the artist name of the music included in the sound source data.
The file name 740 is a file name of sound source data.
The storage location 750 is information indicating whether the sound source data is stored in the sound source storage 520 or the SD card attached to the SD card reader 525.

The directory 760 is a directory in which sound source data is stored.
The genre 770 is a genre of music included in the sound source data. The genre includes, for example, classic, pop, jazz and the like.
The sound source table storage unit 650 updates the stored sound source table 700 when the sound source data stored in the sound source storage unit 645 is updated or when the SD card of the SD card reader 525 is attached or detached.

Returning to FIG. 6 again, the description of the cutoff frequency control unit 600 will be continued.
The user operation reception unit 620 is connected to the control unit 610 and is realized by the CPU 500, the touch panel controller 515, and the touch panel 110. And it has the function to receive the reproduction | regeneration music designation | designated operation and music reproduction operation which are made by the user using the portable terminal 100 touching the operation surface of the touch panel 110.

The reproduction music designation operation is an operation in which a user using the mobile terminal 100 designates one or more music pieces to be reproduced by the mobile terminal 100.
The reception of the reproduction music designation operation is started when a user using the portable terminal 100 performs a predetermined operation on the touch panel 110 (for example, a touch operation of an icon indicating that the reproduction music designation operation is accepted).

FIG. 8 is a schematic diagram showing a reproduction music designation screen 800 displayed on the touch panel 110 when reception of a reproduction music designation operation is started by the user operation reception unit 620.
As shown in the figure, in the reproduction music designation screen 800, an artist name 810, a song name 820, a genre 830, and a storage location 840 are associated with each of the sound source data stored in the sound source storage unit 645. Configured.

The artist name 810 is the artist name of the music included in the sound source data, and is the same as the artist name 730.
The song title 820 is the song title of the song included in the sound source data, and is the same as the song title 720.
The genre 830 is a genre of music included in the sound source data, and is the same as the genre 770.

The storage location 840 is information indicating whether the sound source data is stored in the sound source storage 520 or the SD card attached to the SD card reader 525, and is the same as the storage location 750.
If the artist name 810, song name 820, genre 830, and storage location 840 cannot be fully displayed on one screen (hereinafter referred to as “music information combination”), the screen is scrolled. By performing the operation, a new combination of music information is displayed.

A user who uses the mobile terminal 100 touches the display portion of the combination of music information corresponding to the music to be played back on the mobile terminal 100, thereby designating the music as music to be played back on the mobile terminal 100.
When a plurality of music pieces are designated, the designated order is the order in which the music pieces are reproduced.

Also, the selected music is displayed separately from the unselected music by displaying the selected mark 850a and the selected mark 850b superimposed on the corresponding music information display portion. The
The music playback operation is an operation in which the user using the mobile terminal 100 causes the mobile terminal 100 to play back the music specified by the playback music specifying operation.

The music playback operation is received by a user using the mobile terminal 100 performing a predetermined operation (for example, an icon touch operation indicating that the music playback operation is received) on the touch panel 110.
Returning to FIG. 6 again, the description of the cutoff frequency control unit 600 will be continued.
The reproduction table storage unit 635 is connected to the control unit 610 and is realized by the CPU 500 and the memory 530. And it has the function to produce | generate and memorize | store the reproduction | regeneration table 900 which shows the information about the sound source data of the music designated by the reproduction music designation | designated operation performed by the user who uses the portable terminal 100. FIG.

FIG. 9 is a data configuration diagram of a reproduction table stored in the reproduction table storage unit 635.
As shown in the figure, the playback table 900 includes a playback order 910, an ID 920, and a file name 930 for each piece of music data specified by the playback music specifying operation received by the user operation receiving unit 620. The storage location 940, the directory 950, and the genre 960 are associated with each other.

The reproduction order 910 is the order in which the music of the sound source data is reproduced.
ID 920 is an identifier for identifying sound source data, and is the same as ID 710.
The file name 930 is the file name of the sound source data, and is the same as the file name 740.

The storage location 940 is information indicating whether the sound source data is stored in the sound source storage 520 or the SD card attached to the SD card reader 525, and is the same as the storage location 750.
The directory 950 is a directory in which sound source data is stored, and is the same as the directory 760.

The genre 960 is a genre of music included in the sound source data, and is the same as the genre 770.
Returning to FIG. 6 again, the description of the cutoff frequency control unit 600 will be continued.
The notification table storage unit 640 is connected to the control unit 610 and realized by the memory 530. And it has the function to memorize | store the alerting | reporting table 1000 which shows the information about the sound source data of the music previously defined as alerting | reporting sound.

Here, the notification sound refers to a sound that is output to urge the user who uses the mobile terminal 100 to call attention.
FIG. 10 is a data configuration diagram of the notification table 1000 stored in the notification table storage unit 640.
As shown in the figure, the notification table 1000 includes a notification type 1010, an ID 1020, a file name 1030, a storage location 1040, and a directory 1050 for each of the sound source data of the music previously defined as the notification sound. Configured in association with each other.

The notification type 1010 is a type of notification sound. Examples of the type of notification sound include a ring tone, a mail reception sound, a warning sound, and the like.
ID 1020 is an identifier for identifying sound source data, and is the same as ID 710.
The file name 1030 is a file name of the sound source data and is the same as the file name 740.

The storage location 1040 is information indicating whether the sound source data is stored in the sound source storage 520 or the SD card attached to the SD card reader 525, and is the same as the storage location 750.
The directory 1050 is a directory in which sound source data is stored, and is the same as the directory 760.

Returning to FIG. 6 again, the description of the cutoff frequency control unit 600 will be continued.
The notification instruction receiving unit 625 is connected to the control unit 610 and realized by the CPU 500. And it has the function to receive the notification instruction | indication signal which instruct | indicates the reproduction | regeneration notification sound transmitted from the functional block (not shown) outside the cutoff frequency control part 600. FIG. This notification instruction signal includes a notification type 1010 for specifying the music of the notification sound to be reproduced.

  For example, when a standby function block (not shown) that realizes the standby function receives a new call signal at the time of standby, a music piece indicating that the new call signal has been received is stored in the portable terminal 100. In order to output, a notification instruction signal including a notification type 1010 indicating a ringtone is sent to the notification instruction receiving unit 625. In addition, a mail transmission / reception function block (not shown) that realizes a mail transmission / reception function receives a mail in order to cause the portable terminal 100 to output a song indicating that a new mail has been received when a new mail is received. A notification instruction signal including a notification type 1010 indicating a received sound is transmitted to the notification instruction receiving unit 625.

The remaining amount measuring unit 630 is connected to the control unit 610, and is realized by the CPU 500, the timer 545, and the battery remaining amount measuring device 550. The battery 555 has a function of measuring the remaining amount of power stored in the battery 555.
The predetermined amount storage unit 615 is connected to the control unit 610 and realized by the memory 530. And it has a function which memorizes predetermined amount (for example, 15%) in the remaining amount of a battery defined beforehand.

The sound source reading unit 655 is connected to the sound source storage unit 645 and the control unit 610 and is realized by the CPU 500. The sound source data designated by the control unit 610 is read from the sound source storage unit 645 and sent to the decoding unit 660.
The decoding unit 660 is connected to the sound source reading unit 655 and the buffer unit 665 and is realized by the decoder 560. Then, from the sound source data transmitted from the sound source reading unit 655, the encoded stereo audio data included in the sound source data is decoded to generate a right audio signal and a left audio signal, and the generated right audio signal And the left audio signal are sequentially sent to the buffer unit 665.

The buffer unit 665 is connected to the decoding unit 660 and the constant variable low-pass filter unit 670 and is realized by the decoder 560. The following buffering function, music start notification function, and music completion notification function are provided.
The buffering function temporarily stores the right audio signal and the left audio signal sequentially sent from the decoding unit 660, and adjusts the timing to send the corresponding music so that it is reproduced at the correct timing. This is a function of sequentially transmitting the right audio signal and the left audio signal stored temporarily to the constant variable low-pass filter unit 670.

The music start notification function is a music start indicating that the transmission of the audio signal corresponding to the music starts at the timing of starting the transmission of the audio signal corresponding to the music to the constant variable low-pass filter unit 670. This is a function for sending a notification signal to the control unit 610.
The music completion notification function is the completion of music indicating that the transmission of the audio signal corresponding to the music is completed at the timing when the transmission of the audio signal corresponding to the music is completed to the constant variable low-pass filter unit 670 A function of sending a notification signal to the control unit 610.

  The constant variable low-pass filter unit 670 is connected to the buffer unit 665, the control unit 610, the first amplifier 565, and the second amplifier 570, and the cutoff frequency realized by the decoder 560 and the CPU 500 is programmable. It is a settable digital low-pass filter. Then, for each of the right audio signal and the left audio signal sequentially transmitted from the buffer unit 665, the high frequency component in the frequency band corresponding to the cutoff frequency set by the control unit 610 is cut so that the high frequency component is The cut right audio signal and the left audio signal from which the high frequency component is cut are generated and sent to the first amplifier 565 and the second amplifier 570, respectively.

  The control unit 610 includes a predetermined amount storage unit 615, a user operation reception unit 620, a notification instruction reception unit 625, a remaining amount measurement unit 630, a reproduction table storage unit 635, a notification table storage unit 640, and a sound source table storage. Unit 650, sound source reading unit 655, buffer unit 665, and constant variable low-pass filter unit 670 are realized by CPU 500. The following reproduction table generation control function, sound source data notification function, and filter constant setting function are provided.

The reproduction table generation control function refers to a reproduction table storage unit 635 that generates and stores a reproduction table 900 based on an accepted reproduction music designation operation when a reproduction music designation operation is accepted by the user operation acceptance unit 620. It is a function to let you.
The sound source data notification function is a function for identifying sound source data to be played back by the mobile terminal 100 and notifying the sound source reading unit 655 as sound source data that is read from the sound source storage unit 645.

The filter constant setting function is a function for setting the cutoff frequency of the constant variable low-pass filter unit 670.
The operation performed by the mobile terminal 100 having the above configuration will be described below with reference to the drawings.
<Operation>
Here, a cut-off frequency control process that is a characteristic operation among the operations performed by the mobile terminal 100 will be described.

<Cutoff frequency control process>
The cut-off frequency control process is a process performed by the mobile terminal 100 and is constant when the remaining amount of the battery 555 is greater than a predetermined amount (for example, 15%) when the mobile terminal 100 outputs sound. The cutoff frequency of the variable low-pass filter unit 670 is set to the first frequency (for example, 10 KHz), and the cutoff frequency of the constant variable low-pass filter unit 670 is lower than the first frequency when the remaining amount of the battery 555 is equal to or less than a predetermined amount. This is processing for setting the second frequency (for example, 5 KHz).

This cut-off frequency control processing is further performed during the period during which one piece of music is being played, even when the remaining amount of the battery 555 is greater than a predetermined amount and less than the predetermined amount. Without changing the off-frequency, wait for the music to finish playing, and then change the cut-off frequency.
FIG. 11 is a flowchart of the cut-off frequency control process.

The cut-off frequency control process is started when a music playback operation is received by the user operation receiving unit 620 or when a notification instruction signal is received by the notification instruction receiving unit 625.
When the cut-off frequency control process is started, the control unit 610 notifies the audio to be played back when the cut-off frequency control process is started when the notification instruction receiving unit 625 receives the notification instruction signal. When it is determined that the sound is a sound and the cut-off frequency control process is started when the user operation reception unit 620 receives a music reproduction operation, the sound to be reproduced is determined not to be a notification sound (step S1100). .

  In the process of step S1100, when it is determined that the sound to be reproduced is a notification sound (step S1100: Yes), the control unit 610 refers to the notification table 1000 stored in the notification table storage unit 640. Then, the music corresponding to the notification type 1010 included in the notification instruction signal received by the notification instruction receiving unit 625 (hereinafter referred to as “notification music”) is specified (step S1105).

  When it is determined in step S1100 that the sound to be reproduced is not a notification sound (step S1100: No), the control unit 610 refers to the reproduction table 900 stored in the reproduction table storage unit 635. One or more pieces of music (hereinafter referred to as “playback music group”) designated by the reproduction music designation operation accepted by the user operation accepting unit 620 and their reproduction order are specified.

When the process of step S1105 is completed or when the process of step S1110 is completed, the remaining amount measuring unit 630 measures the remaining amount of power stored in the battery 555, and the control unit 610 is measured. It is checked whether the remaining amount is equal to or less than a predetermined amount (for example, 15%) stored in the predetermined amount storage unit 615 (step S1115).
When the measured remaining amount is equal to or smaller than the predetermined amount stored in the predetermined amount storage unit 615 in the process of step S1115 (step S1115: Yes), the control unit 610 cuts the constant variable low-pass filter unit 670. The off frequency is set to the second frequency (step S1120).

  When the cut-off frequency of the constant variable low-pass filter unit 670 is set to the second frequency, the control unit 610 causes the sound source reading unit 655 to (1) the informing music specified in the process of step S1105, or (2) Reading of the reproduction music group specified in the process of step S1110 is started (step S1125). That is, (1) when the process of step S1105 has been performed, the control unit 610 refers to the notification table 1000 stored in the notification table storage unit 640, and determines the notification music specified in the process of step S1105. The set of the file name 1030, the storage location 1040, and the directory 1050 is sent to the sound source reading unit 655, and causes the sound source reading unit 655 to start reading the specified music for notification. Then, (2) when the process of step S1110 has been performed, the control unit 610 refers to the reproduction table 900 stored in the reproduction table storage unit 635, and the reproduction music group specified in the process of step S1110. Each set of playback order 910, file name 930, storage location 940, and directory 950 is sent to the sound source reading unit 655, and the playback order of the specified playback music group is sent to the sound source reading unit 655. Start reading.

  When the sound source reading unit 655 starts reading of the notification music or reading of the playback music group in the playback order, the decoding unit 660 reads the notification music or playback music that has been read by the sound source reading unit 655. The group is sequentially decoded, and the decoded right audio signal and left audio signal are sequentially transmitted to the buffer unit 665. Then, the buffer unit 665 adjusts the timing for sequentially transmitting the right audio signal and the left audio signal sequentially transmitted from the decoding unit 660, and transmits them to the constant variable low-pass filter unit 670. Then, the constant variable low-pass filter unit 670 has a frequency band corresponding to the cutoff frequency sequentially set by the control unit 610 for the right audio signal and the left audio signal sequentially transmitted from the constant variable low-pass filter unit 670. The high frequency components are cut and sent to the first amplifier 565 and the second amplifier 570, respectively.

In the process of step S1115, when the measured remaining amount is not less than or equal to the predetermined amount stored in the predetermined amount storage unit 615 (step S1115: No), the control unit 610 cuts off the constant variable low-pass filter unit 670. The frequency is set to the first frequency (step S1130).
When the cut-off frequency of the constant variable low-pass filter unit 670 is set to the first frequency, the control unit 610 instructs the sound source reading unit 655 to (1) the music for notification identified in the process of step S1105, or (2). Reading of the reproduction music group specified in the process of step S1110 is started (step S1135). The process in step S1135 is equivalent to the process in step S1125.

  When the sound source reading unit 655 starts reading the specified notification music piece or the specified reproduction music group in the playback order, the control unit 610 starts measuring time using the timer 545 (step S1140). ) After waiting for elapse of a predetermined time T1 (for example, 20 seconds) (Step S1145: No after repeating Step S1145: Yes), the buffer section 665 is still in the notification music or the reproduction music group. By checking whether there is a song for which a music completion notification signal has not been transmitted from the music for notification or the music group for reproduction, it is checked whether there is a song that has not yet been played. (Step S1150).

In the process of step S1150, when there is a piece of music that has not yet been played back (step S1150: Yes), the remaining amount measuring unit 630 measures the remaining amount of power stored in the battery 555, and the control unit 610 Checks whether or not the measured remaining amount is equal to or less than the predetermined amount stored in the predetermined amount storage unit 615 (step S1155).
When the measured remaining amount is equal to or less than the predetermined amount stored in the predetermined amount storage unit 615 (step S1155: Yes), the control unit 610 transmits a music start notification signal from the buffer unit 665. Is checked whether or not a music completion notification signal has been transmitted from the buffer unit 665 to check whether or not the music is currently being reproduced (step S1160).

In the process of step S1160, when the music is currently being played back (step S1160: Yes), the control unit 610 waits until the music being played ends, that is, the music start notification signal is finally received from the buffer unit 665. About the sent music, it waits until the music completion notification signal is transmitted from the buffer unit 665 (step S1165).
In the process of step S1160, when the music is not currently being reproduced (step S1160: No), or when the process of step S1165 is completed, the control unit 610 sets the cutoff frequency of the constant variable low-pass filter unit 670 as the second frequency. (Step S1170). This setting is made during a period until the reproduction of the music starts when there is a music to be reproduced next.

In the process of step S1155, when the measured remaining amount is not less than or equal to the predetermined amount stored in the predetermined amount storage unit 615 (step S1155: No), the mobile terminal 100 returns to step S1140 and performs the subsequent processing. repeat.
When the process of step S1125 is completed, or when the process of step S1170 is completed, the control unit 610 waits until there is no music that has not yet been played back (step S1175: after repeating Yes, In step S1175: No), the cutoff frequency control process performed by the mobile terminal 100 is terminated.

Also, in the process of step S1150, when there is no music that has not yet been played back (step S1150: No), the control unit 610 ends the cutoff frequency control process performed by the mobile terminal 100.
<Discussion>
According to the portable terminal 100, when the music group is being reproduced, when the remaining amount of the battery 555 decreases and becomes a predetermined amount or less, the cutoff frequency of the constant variable low-pass filter unit 670 is changed from the first frequency to the first frequency. The frequency is changed to a second frequency lower than the frequency. For this reason, although the sound quality of the high sound range of the sound output from the film speaker 200a and the film speaker 200b is reduced, the power consumed by the film speaker 200a and the film speaker 200b is reduced.

As a result, when the portable terminal 100 is playing back a music group, when the remaining amount of the battery 555 decreases and becomes less than a predetermined amount, the time when the battery runs out in exchange for a decrease in sound quality Can be postponed.
Also, according to the portable terminal 100, when the remaining amount of the battery 555 decreases while a certain piece of music is being played, the first frequency is increased until the playback of the song ends. The cut-off frequency from the first frequency to the second frequency during the period from when the reproduction of the music is finished until the reproduction of the next music is started by suppressing the change of the cut-off frequency to the second frequency. Changes are made.

Thus, the mobile terminal 100 does not make the user who uses the device feel uncomfortable that the sound quality is changed during the reproduction of one piece of music.
In the flowchart of FIG. 11, when there is no music that has not yet been played back (step S1175: NO, step S1150: NO), the control unit 610 ends the cutoff frequency control process performed by the mobile terminal 100. However, when the power of the mobile terminal 100 is turned off or when the remaining battery power is exhausted, the process ends even during the cutoff frequency control process.
<Modification 1>
<Overview>
Here, as an embodiment of the mobile terminal according to the present invention, a mobile terminal of a first modified example in which a part of the mobile terminal 100 in the embodiment is modified will be described.

In the portable terminal 100 according to the embodiment, the constant variable low-pass filter unit 670 sets (1) the cutoff frequency as the first frequency when the remaining amount of the battery 555 is larger than a predetermined amount, and (2) the remaining amount of the battery 555. When the value is equal to or less than the predetermined amount, the cutoff frequency is set to the second frequency lower than the first frequency.
As a result, in the portable terminal 100 according to the embodiment, (1) when the remaining amount of the battery 555 is larger than a predetermined amount, the frequency components equal to or higher than the first frequency are cut in the film speaker 200a and the film speaker 200b. (2) When the remaining amount of the battery 555 is equal to or less than a predetermined amount, a signal from which a frequency component equal to or higher than the second frequency is cut is input.

  On the other hand, the mobile terminal of the first modification example in the first modification example has a cutoff frequency between the first amplifier 565 and the film speaker 200a and between the second amplifier 570 and the film speaker 200b, respectively. Includes a constant fixed low-pass filter fixed at the first frequency, and the constant variable low-pass filter unit 670 (1) outputs the high-frequency component as it is without being cut when the remaining amount of the battery 555 is greater than a predetermined amount, ( 2) When the remaining amount of the battery 555 is equal to or less than a predetermined amount, the cutoff frequency is set to a second frequency lower than the first frequency.

  Accordingly, in the mobile terminal of the first modification example of the first modification example, (1) the remaining amount of the battery 555 is provided between the film speaker 200a and the film speaker 200b, as in the mobile terminal 100 in the embodiment. When the amount is higher than the fixed amount, a signal in which the frequency component equal to or higher than the first frequency is cut is input. (2) When the remaining amount of the battery 555 is equal to or less than the predetermined amount, the frequency component equal to or higher than the second frequency is cut. Signal is input.

Hereinafter, the details of the mobile terminal according to the first modification will be described with reference to the drawings, focusing on differences from the mobile terminal 100 according to the embodiment.
<Configuration>
FIG. 12 is a block diagram illustrating a circuit configuration of the mobile terminal according to the first modification.
As shown in the figure, the mobile terminal of the first modification is fixed to the first constant 565 between the first amplifier 565 and the film speaker 200a with respect to the mobile terminal 100 (see FIG. 5) in the embodiment. A low pass filter 1210 is added, and the second constant fixed low pass filter 1220 is added between the second amplifier 570 and the film speaker 200b.

The first constant fixed low-pass filter 1210 cuts a high frequency component equal to or higher than the first frequency (for example, 10 KHz) with respect to the analog signal output from the first amplifier 565, and has a cutoff frequency fixed at the first frequency. It is a filter. As an example, it is realized by an inductor and a capacitor.
The second constant fixed low-pass filter 1220 is a low-pass filter whose cutoff frequency is fixed at the first frequency, similar to the first constant fixed low-pass filter 1210.

The operation performed by the mobile terminal of the first modified example having the above configuration will be described below with reference to the drawings.
<Operation>
The mobile terminal of the first modified example is modified from the mobile terminal 100 in the embodiment so that a part of the program to be executed is changed in addition to the change in the circuit configuration. Thus, the cut-off frequency control process of the first modification is performed instead of the cut-off frequency control process in the embodiment.

  The cut-off frequency control process of the first modification is a process in which a part of the cut-off frequency control process in the embodiment is modified, and when the remaining amount of the battery 555 is larger than a predetermined amount, the constant variable low-pass This is processing for preventing the filter unit 670 from cutting high-frequency components and setting the cutoff frequency of the constant variable low-pass filter unit 670 as the second frequency when the remaining amount of the battery 555 is equal to or less than a predetermined amount.

Hereinafter, the cutoff frequency control process of the first modification will be described with reference to the drawings.
<Cutoff frequency control process of first modification>
The cut-off frequency control process of the first modification is a process modified so that a part of the process is changed from the cut-off frequency control process performed by the mobile terminal 100 in the embodiment.

FIG. 13 is a flowchart of the cutoff frequency control process of the first modification.
The processes in steps S1300 to S1325 and the processes in steps S1335 to S1375 in the cutoff frequency control process of the first modified example are the processes in steps S1100 to S1125 in the cutoff frequency control process (see FIG. 11), respectively. The processing is the same as the processing in steps S1135 to S1175. Therefore, these processes have already been described.

Hereinafter, the processing in step S1330 will be mainly described.
In the process of step S1315, when the measured remaining amount is not less than or equal to the predetermined amount stored in the predetermined amount storage unit 615 (step S1315: No), the control unit 610 changes the constant variable low-pass filter unit 670 to the high frequency. It sets so that a component may be output as it is without being cut (step S1330).

When the process of step S1330 ends, the mobile terminal of the first modification proceeds to the processes after step S1335.
<Modification 2>
<Overview>
Here, as an embodiment of the mobile terminal according to the present invention, a mobile terminal of a second modified example in which a part of the mobile terminal of the first modified example in the modified example 1 is modified will be described.

The mobile terminal according to the first modification of the first modification has a constant variable low-pass depending on whether or not the remaining amount of the battery 555 is equal to or less than a predetermined amount regardless of whether or not the sound to be reproduced is a notification sound. The filter unit 670 has a configuration in which either the high frequency component is not cut or the cutoff frequency is set to the second frequency.
On the other hand, in the mobile terminal of the second modification example of the second modification example, (1) when the reproduction target voice is a notification sound, as in the mobile terminal of the first modification example of the first modification example, Depending on whether the remaining amount of the battery 555 is equal to or less than a predetermined amount, the constant variable low-pass filter unit 670 is set to either not cut the high frequency component or set the cutoff frequency to the second frequency, (2) When the sound to be reproduced is not a notification sound, it is set not to cut a high-frequency component regardless of the remaining amount of the battery 555, that is, the cut-off frequency is suppressed from being set as the second frequency. It is the composition which becomes.

Hereinafter, details of the mobile terminal of the second modification will be described with reference to the drawings, centering on differences from the mobile terminal of the first modification in Modification 1.
<Configuration>
The mobile terminal of the second modification has the same circuit configuration as the mobile terminal of the first modification in modification 1.

The operation performed by the mobile terminal of the second modification will be described below with reference to the drawings.
<Operation>
The mobile terminal of the second modification is modified from the mobile terminal of the first modification in Modification 1 so that a part of the program to be executed is changed. Then, instead of the cut-off frequency control process of the first modification in the first modification, the cut-off frequency control process of the second modification is performed.

The cut-off frequency control process of the second modification is a process in which a part of the first cut-off frequency control process in the first modification is modified, and the battery 555 is used when the sound to be reproduced is not a notification sound. The constant variable low-pass filter unit 670 prevents the high-frequency component from being cut regardless of the remaining amount.
Hereinafter, the cutoff frequency control process of the second modification will be described with reference to the drawings.

<Cutoff Frequency Control Processing of Second Modification>
The cut-off frequency control process of the second modified example is a process modified so that a part of the process is changed from the cut-off frequency control process of the first modified example in the modified example.
FIG. 14 is a flowchart of a cutoff frequency control process according to the second modification.
In the cut-off control process of the second modification, the processes of Step S1400 to Step S1410, the processes of Step S1415 to Step S1420, the process of Step S1430, the processes of Step S1440 to Step S1445, and the process of Step S1455 are respectively performed. In the cut-off control process (see FIG. 13) of the first modified example, the process from step S1300 to step S1310, the process from step S1315 to step S1320, the process from step S1430, the process from step S1340 to step S1345, the process from step S1355, It is the same processing. Therefore, these processes have already been described.

Hereinafter, the processing from step S1412 to step S1414, the processing from step S1425, the processing from step S1435, the processing from step S1450, and the processing from step S1475 will be mainly described.
When the process of step S1410 ends, control unit 610 sets constant variable low-pass filter unit 670 to output the high-frequency component as it is without cutting (step S1412).

When the constant variable low-pass filter unit 670 is set to output the high-frequency component as it is without being cut, the control unit 610 reads out the reproduction music group specified in step S1410 to the sound source reading unit 655. Is started (step S1413).
When reading of the music group for reproduction is started, the control unit 610 waits until there is no music that has not yet been reproduced (step S1414: after repeating Yes, step S1414: No), and then the mobile terminal 100 The cut-off frequency control process of the second modified example performed is terminated.

When the process of step S1420 ends, control unit 610 causes sound source reading unit 655 to start reading the notification music specified in the process of step S1405 (step S1425).
When reading of the music for notification is started, the control unit 610 waits until the reproduction of the music for notification is completed (step S1475: After repeating No, step S1475: Yes), the second modification performed by the mobile terminal 100 is performed. The example cut-off frequency control process is terminated.

When the process of step S1430 ends, the control unit 610 causes the sound source reading unit 655 to start reading the notification music specified in the process of step S1405 (step S1435). The process of step S1435 is the same process as the process of step S1425.
In the process of step S1445, when the predetermined time T1 has elapsed (step S1445: Yes), the control unit 610 checks whether or not the reproduction of the notification music has been completed (step S1450).

In the process of step S1450, when the reproduction of the music for notification is not completed (step S1450: No), the process proceeds to step S1455.
When the measured remaining amount is equal to or less than the predetermined amount stored in the predetermined amount storage unit 615 in the process of step S1455 (step S1455: Yes), the process proceeds to step S1420.

In the process of step S1450, when the reproduction of the music for notification is completed (step S1450: Yes), the control unit 610 ends the cutoff frequency control process of the second modification performed by the mobile terminal 100.
<Discussion>
The first frequency is higher than the second frequency. Therefore, when the signal from which the frequency component of the first frequency or higher is cut is input to the film speaker 200a and the film speaker 200b, the sound quality of the sound output is higher than the second frequency. When the signal is input to the film speaker 200a and the film speaker 200b, the sound quality is higher than the sound quality of the sound output.

According to the mobile terminal of the second modified example, when playing a playback music group that is not a notification sound, setting the cut-off frequency to the second frequency is suppressed, and the first frequency is suppressed regardless of the remaining amount of the battery 555. A signal from which a frequency component of one frequency or more is cut is input to the film speaker 200a and the film speaker 200b.
As a result, the portable terminal of the second modified example is compared with the user who uses it when playing a music group for playback that is not a notification sound even when the remaining amount of the battery 555 is equal to or less than a predetermined amount. High quality sound can be provided.
<Modification 3>
<Overview>
Here, as an embodiment of the mobile terminal according to the present invention, a mobile terminal of a third modified example in which a part of the mobile terminal of the first modified example in the modified example 1 is modified will be described.

In the mobile terminal of the first modification in Modification 1, if the sound to be played is a music that is not a notification sound, regardless of the genre of the music, even if the remaining amount of the battery 555 is equal to or less than a predetermined amount, The constant variable low-pass filter unit 670 is configured so as not to cut high-frequency components.
On the other hand, in the mobile terminal of the third modification example of the third modification example, when the sound to be reproduced is a music that is not a notification sound, (1) when the music is a music of a genre designated by the user Even if the remaining amount of the battery 555 is equal to or less than the predetermined amount, the constant variable low-pass filter unit 670 is set not to cut the high frequency component. (2) When the music is not a music of the genre designated by the user, the battery If the remaining amount of 555 is equal to or less than the predetermined amount, the constant variable low-pass filter unit 670 is configured to set the cutoff frequency to the second frequency.

Hereinafter, the details of the mobile terminal of the third modification will be described with reference to the drawings, centering on differences from the mobile terminal of the first modification in Modification 1.
<Configuration>
The mobile terminal of the third modified example has the same circuit configuration as the first modified terminal in the modified example 1, but is modified so that a part of the program to be executed is changed. Thus, the cut-off frequency control unit 600 (see FIG. 6: the same as the cut-off frequency control unit 600 in the embodiment) in the first modification is transformed into the cut-off frequency control unit 1500.

FIG. 15 is a block diagram illustrating a functional configuration of the cutoff frequency control unit 1500.
As shown in the figure, in the cutoff frequency control unit 1500, a genre storage unit 1575 is added to the cutoff frequency control unit 600 in the first modification, and the user operation reception unit 620 is changed to a user operation reception unit 1520. The control unit 610 is modified to be changed to the control unit 1510.

The user operation accepting unit 1520 has a function of accepting the following genre designating operations in addition to the reproduction music designation operation and the music reproduction operation that the user operation accepting unit 620 in Modification 1 has.
The genre designation operation is an operation in which a user who uses the mobile terminal of the third modification designates a genre that the user likes among genres 770 included in the sound source table 700.

The genre designation operation is accepted when a user using the mobile terminal of the third modification performs a predetermined operation (for example, an icon touch operation indicating that the genre designation operation is accepted) on the touch panel 110. Is called.
The genre storage unit 1575 is connected to the control unit 1510 and is realized by the memory 530. And it has the function to memorize | store the genre designated by the genre designation | designated operation performed by the user who utilizes the portable terminal of a 3rd modification.

The control unit 1510 has the following genre storage control function in addition to the reproduction table generation control function, the sound source data notification function, and the filter constant setting function that the control unit 610 in Modification 1 has.
The genre storage control function is a function for storing the specified genre in the genre storage unit 1575 based on the received genre specifying operation when the user operation receiving unit 1520 receives the genre specifying operation. .

An operation performed by the mobile terminal of the third modified example having the above configuration will be described below with reference to the drawings.
<Operation>
The mobile terminal of the third modification example performs the cutoff frequency control process of the third modification example instead of the cutoff frequency control process of the first modification example of the modification example 1.

The cutoff frequency control process of the third modified example is a process in which a part of the first cutoff frequency control process in the modified example 1 is modified, and the sound to be reproduced is a genre designated by the user. In some cases, the constant variable low-pass filter unit 670 prevents the high-frequency component from being cut regardless of the remaining amount of the battery 555.
Hereinafter, the cutoff frequency control process of the third modification will be described with reference to the drawings.

<Cutoff frequency control process of the third modification>
The cutoff frequency control process of the third modification is modified so that a part of the process is changed from the cutoff frequency control process of the first modification performed by the mobile terminal of the first modification in Modification 1. Process.
16 and 17 are flowcharts of the cut-off frequency control process of the third modification.

  In the cutoff frequency control process of the third modified example, the processes in steps S1600 to S1610 and the processes in steps S1615 to S1670 are respectively performed in step S1300 in the cutoff frequency control process (see FIG. 13) of the first modified example. To Step S1310 and Step S1315 to Step S1370. Therefore, these processes have already been described. However, it is necessary to replace the control unit 610 with the control unit 1510 and the user operation reception unit 620 with the user operation reception unit 1520.

Hereinafter, the processing in step S1612, the processing in step S1675, and the processing in steps S1710 to S1750 will be mainly described.
When the process of step S1610 ends, the control unit 1510 refers to the reproduction table 900 stored in the reproduction table storage unit 635, and the music to be reproduced first is stored in the genre storage unit 1575 and designated by the user. It is checked whether or not the genre is designated (hereinafter referred to as “designated genre”) (step S1612).

In the process of step S1612, when the music to be reproduced first is the designated genre (step S1612: Yes), the process proceeds to step S1630, and when the music to be reproduced first is not the designated genre (step S1612: No). ), The process proceeds to step S1615.
When the process of step S1625 ends, or when the process of step S1670 ends, the control unit 1510 still transmits a music completion notification signal from the buffer unit 665 in the notification music or the reproduction music group. By checking whether or not there is a song that has not been played, it is checked whether or not there is a song that has not yet been played back in the notification song or the playback song group (step S1675).

  In the process of step S1675, when there is a piece of music that has not yet been played back (step S1675: Yes), the control unit 1510 refers to the playback table 900 stored in the playback table storage unit 635, and plays back next. It is checked whether or not the music to be played is the designated genre stored in the genre storage unit 1575 (step S1710: see FIG. 17). Here, if there is no music to be reproduced next, it is assumed that the music to be reproduced next is not a designated genre stored in the genre storage unit 1575.

  In the process of step S1710, when the music to be reproduced next is the designated genre (step S1710: Yes), the control unit 1510 uses the buffer unit for the music for which the music start notification signal was last transmitted from the buffer unit 665. By checking whether or not the music completion notification signal is transmitted from 665, it is checked whether or not the music is currently being reproduced (step S1720).

In the process of step S1720, when the music is currently being played back (step S1720: Yes), the control unit 1510 waits until the music being played ends, that is, the music start notification signal is finally received from the buffer unit 665. About the sent music, it waits until a music completion notification signal is transmitted from the buffer unit 665 (step S1730).
In the process of step S1720, when the music is not currently being played back (step S1720: No), or when the process of step S1730 ends, the control unit 1510 does not cut the constant variable low-pass filter unit 670 without cutting the high frequency component. (Step S1740). This setting is made during a period until the reproduction of the music starts when there is a music to be reproduced next.

When the process of step S1740 ends, the process proceeds to step S1640.
In the process of step S1710, when the music to be reproduced next is not the designated genre (step S1710: No), the process proceeds to step S1675.
When the process of step S1665 ends, the control unit 1510 refers to the reproduction table 900 stored in the reproduction table storage unit 635, and the music to be reproduced next is a designated genre stored in the genre storage unit 1575. Whether or not (step S1750). Here, if there is no music to be reproduced next, it is assumed that the music to be reproduced next is not a designated genre stored in the genre storage unit 1575.

In the process of step S1750, when the music to be reproduced next is the designated genre (step S1750: Yes), the process proceeds to the process of step S1640, and when the music to be reproduced next is not the designated genre (step S1750: No). ), The process proceeds to step S1670.
In the process of step S1675, when there is no music that has not yet been played back (step S1675: No), the control unit 1510 performs the cutoff frequency control process of the third modification performed by the mobile terminal of the third modification. Terminate.

<Discussion>
According to the mobile terminal of the third modified example, when the music of the genre designated as the user's preference is not a notification sound, setting the cutoff frequency as the second frequency is suppressed, and the battery Regardless of the remaining amount of 555, the signal from which the frequency component equal to or higher than the first frequency is cut is input to the film speaker 200a and the film speaker 200b.

As a result, when the mobile terminal of the third modified example reproduces music of a genre designated as a user's preference that is not a notification sound even when the remaining amount of the battery 555 is equal to or less than a predetermined amount. Therefore, it is possible to provide a relatively high sound quality to the user who uses the device.
<Modification 4>
<Overview>
Here, as an embodiment of the mobile terminal according to the present invention, a mobile terminal of a fourth modified example in which a part of the mobile terminal of the first modified example in the modified example 1 is modified will be described.

The mobile terminal of the first modified example in the modified example 1 includes a constant variable low-pass filter unit 670 (see FIG. 6: the same as the constant variable low-pass filter unit 670 in the embodiment) that can set the cutoff frequency in a programmable manner. It was a configuration.
On the other hand, the mobile terminal of the fourth modified example in the modified example 4 does not include the constant variable low-pass filter unit 670 that can set the cutoff frequency in a programmable manner, but instead has a constant fixed low-pass with a fixed cutoff frequency. A plurality of types of filters are provided, and a constant fixed low-pass filter to be used is selected in accordance with a high frequency region to be cut.

Hereinafter, the details of the mobile terminal of the fourth modification will be described with reference to the drawings, centering on differences from the mobile terminal of the first modification in Modification 1.
<Configuration>
FIG. 18 is a block diagram illustrating a circuit configuration of a mobile terminal according to a fourth modification.
As shown in the figure, the mobile terminal of the fourth modified example has a third constant fixed low-pass filter 1810 and a fourth constant fixed to the mobile terminal of the first modified example (see FIG. 12) in the modified example 1. A low-pass filter 1820, a selector 1830, and a selector 1840 are modified to be added.

The third constant fixed low-pass filter 1810 is connected to the first amplifier 565 and the selector 1830, and cuts a high frequency component equal to or higher than the second frequency (for example, 5 KHz) from the analog signal output from the first amplifier 565. The low-pass filter has a cutoff frequency fixed at the second frequency. As an example, it is realized by an inductor and a capacitor.
The fourth constant fixed low-pass filter 1820 is a low-pass filter whose cutoff frequency is fixed at the second frequency, similar to the third constant fixed low-pass filter 1810, and is connected to the second amplifier 570 and the selector 1840.

  The selector 1830 is connected to the first constant fixed low-pass filter 1210, the third constant fixed low-pass filter 1810, the film speaker 200a, and the CPU 500. The selector 1830 receives the output of the first constant fixed low-pass filter 1210 according to a control signal from the CPU 500. The selector is set to select any one of the outputs from the third constant fixed low-pass filter 1810 and output the selected one to the film speaker 200a.

  The selector 1840 is connected to the second constant fixed low-pass filter 1220, the fourth constant fixed low-pass filter 1820, the film speaker 200b, and the CPU 500, and the output of the second constant fixed low-pass filter 1220 is controlled by a control signal from the CPU 500. The selector is set to select one of the outputs from the fourth constant fixed low-pass filter 1820 and output the selected one to the film speaker 200b.

The portable terminal of the fourth modification is further modified so that a part of the program to be executed is changed. Thus, the cut-off frequency control unit 600 in Embodiment 1 (see FIG. 6: the same as the cut-off frequency control unit 600 in the embodiment) is transformed into the cut-off frequency control unit 1900. .
FIG. 19 is a block diagram illustrating a functional configuration of the cutoff frequency control unit 1900.

  As shown in the figure, in the cutoff frequency control unit 1900, the constant variable low-pass filter unit 670 is deleted from the cutoff frequency control unit 600 in the first modification, and the right audio signal output from the buffer unit 665 is the first audio signal. The left audio signal input to the first amplifier 565 and output from the buffer unit 665 is input to the second amplifier 570, the control unit 610 is changed to the control unit 1910, and the signal of the control unit 1910 receives the selectors 1830 and 1840. It has been transformed to be input.

The control unit 1910 has the following modified filter constant setting function in addition to the reproduction table generation control function and the sound source data notification function of the control unit 610 in the first modification.
The modified filter constant setting function sets whether the selector 1830 selects the output of the first constant fixed low-pass filter 1210 or the output of the third constant fixed low-pass filter 1810, and the selector 1840 sets the second constant. This is a function for setting which of the output of the fixed low-pass filter 1220 and the output of the fourth constant fixed low-pass filter 1820 is selected.

An operation performed by the mobile terminal of the fourth modified example having the above configuration will be described below with reference to the drawings.
<Operation>
The mobile terminal of the fourth modification performs the cutoff frequency control process of the fourth modification instead of the cut-off frequency control process of the first modification in Modification 1.

  The cut-off frequency control process of the fourth modification is a process in which a part of the first cut-off frequency control process in the first modification is modified, and when the remaining amount of the battery 555 is greater than a predetermined amount, the selector 1830 and selector 1840 select the output of the first constant fixed low-pass filter 1210 and the output of the second constant fixed low-pass filter 1220, respectively, and when the remaining amount of the battery 555 is less than or equal to a predetermined amount, the selector 1830 and selector 1840 is a process for selecting the output of the third constant fixed low-pass filter 1810 and the output of the fourth constant fixed low-pass filter 1820, respectively.

Hereinafter, the cutoff frequency control process of the fourth modification will be described with reference to the drawings.
<Cutoff Frequency Control Process of Fourth Modification>
The cut-off frequency control process of the fourth modified example is a process modified so that a part of the process is changed from the cut-off frequency control process of the first modified example in the modified example.

FIG. 20 is a flowchart of a cutoff frequency control process according to the fourth modification.
In the cut-off control process of the fourth modified example, the processes of step S2000 to step S2015, the process of step S2025, the process of step S2035 to step S2065, and the process of step S2075 are the cut-off control process of the first modified example ( 13), the same processing as the processing of Step S1300 to Step S1315, the processing of Step S1325, the processing of Step S1335 to Step S1365, and the processing of Step S1375. Therefore, these processes have already been described. However, it is necessary to replace the control unit 610 with the control unit 1910.

Hereinafter, the processing in step S2020, the processing in step S2030, and the processing in step S2070 will be mainly described.
In the process of step S2015, when the measured remaining amount is equal to or less than the predetermined amount stored in the predetermined amount storage unit 615 (step S2015: Yes), the control unit 1910 fixes the third constant to the selector 1830. The output of the low-pass filter 1810 is selected, and the selector 1840 is set to select the output of the fourth constant fixed low-pass filter 1820 (step S2020). As a result, a signal from which a high frequency component equal to or higher than the second frequency is cut is input to the film speaker 200a and the film speaker 200b.

  In the process of step S2015, when the measured remaining amount is not less than or equal to the predetermined amount stored in the predetermined amount storage unit 615 (step S2015: No), the control unit 1910 causes the selector 1830 to send the first constant fixed low pass. The output of the filter 1210 is selected, and the selector 1840 is set to select the output of the second constant fixed low-pass filter 1220 (step S2030). As a result, a signal from which a high frequency component equal to or higher than the first frequency is cut is input to the film speaker 200a and the film speaker 200b.

  In the process of step S2060, when the music is not currently being reproduced (step S2060: No), or when the process of step S2065 is completed, the control unit 1910 outputs the output of the third constant fixed low-pass filter 1810 to the selector 1830. The selector 1840 is set to select the output of the fourth constant fixed low-pass filter 1820 (step S2070).

When the process of step S2070 ends, the process proceeds to step S2075.
<Supplement>
As described above, in the embodiment of the mobile terminal according to the present invention, the mobile terminal 100, the mobile terminal of the first modified example, the first modified example, the modified example 2, the modified example 3, and the modified example 4, respectively, The portable terminal of the second modification, the portable terminal of the third modification, and the portable terminal of the fourth modification have been illustrated and described. However, the present invention can be modified as follows, and the present invention is The portable terminal 100, the portable terminal of the first modified example, the portable terminal of the second modified example, the portable terminal of the third modified example illustrated in the modified example 1, the modified example 2, the modified example 3 and the modified example 4, and Of course, the mobile terminal is not limited to the fourth modification.

  (1) In the embodiment, the mobile terminal 100 has been described assuming that the first frequency is, for example, 10 KHz and the second frequency is, for example, 5 KHz. However, if the second frequency is lower than the first frequency, the first frequency is not necessarily 10 KHz and the second frequency is not necessarily 5 KHz. As an example, an example in which the first frequency is 12 KHz and the second frequency is 7 KHz can be considered.

Further, at least one of the first frequency and the second frequency may be arbitrarily set by the user. In this case, the user can select a frequency or input a frequency using the user operation reception unit.
(2) In the embodiment, in the portable terminal 100, when the predetermined amount storage unit 615 stores one predetermined amount and the remaining amount of the battery 555 is larger than the predetermined amount, the constant variable low-pass filter unit 670 is cut. This is an example of a configuration in which the off-frequency is the first frequency and the cutoff frequency of the constant variable low-pass filter unit 670 is the second frequency lower than the first frequency when the remaining amount of the battery 555 is equal to or less than the predetermined amount. . However, the configuration is not necessarily limited to the above as long as the cutoff frequency of the constant variable low-pass filter unit 670 is changed according to the remaining amount of the battery 555. As an example, when the predetermined amount storage unit 615 stores a first predetermined amount and a second predetermined amount smaller than the first predetermined amount, and the remaining amount of the battery 555 is larger than the first predetermined amount, the constant is variable. When the cutoff frequency of the low-pass filter unit 670 is the first frequency and the remaining amount of the battery 555 is equal to or less than the first predetermined amount and greater than the second predetermined amount, the cutoff frequency of the constant variable low-pass filter unit 670 is set to the first frequency. An example of a configuration in which when the remaining frequency of the battery 555 is less than the second predetermined amount and the cutoff frequency of the constant variable low-pass filter unit 670 is a third frequency lower than the second frequency is considered.

(3) In the embodiment, the mobile terminal 100 has been described assuming that the predetermined amount stored in the predetermined amount storage unit 615 is, for example, 15%. However, it is not necessarily 15%. As an example, an example of a configuration in which the predetermined amount stored in the predetermined amount storage unit 615 is 10% can be considered.
(4) In the embodiment, the mobile terminal 100 has been described on the assumption that the sound source data stored in the sound source storage unit 645 is data encoded according to the MP3 standard, for example. However, the encoding method of the sound source data stored in the sound source storage unit 645 does not necessarily have to be encoded by an encoding method compliant with the MP3 standard, and does not necessarily have to be encoded. When the sound source data stored in the sound source storage unit 645 is not encoded, it is not necessary for the decoding unit 660 to decode it.

  (5) In the embodiment, the mobile terminal 100 uses the audio signal of the decoded music that is sequentially transmitted from the decoding unit 660 as the audio signal temporarily stored in the buffer unit 665 in the cut-off frequency control process. It was an example of a certain configuration. However, in the cut-off frequency control process, the audio signal temporarily stored in the buffer unit 665 is not necessarily limited to the audio signal of the decoded music sequentially transmitted from the decoding unit 660. For example, the voice signal of the other party with whom the mobile terminal 100 is currently communicating, the voice signal of the Internet broadcast program that the mobile terminal 100 is currently receiving, and the SD card attached to the SD card reader 525 are sequentially read. It may be an audio signal of a conference recorded in the past.

  (6) In the embodiment, the mobile terminal 100 is an example of a configuration that includes two film speakers and supports stereo audio output. However, if a process equivalent to the cut-off frequency control process can be realized, the number of film speakers provided is not necessarily limited to two, and does not necessarily correspond to stereo sound output. As an example, an example in which one film speaker is provided and only a monaural sound output is supported without corresponding to a stereo sound output is conceivable. As another example, a configuration example in which six film speakers are provided to realize high-quality stereo sound output can be considered.

  (7) In embodiment, the portable terminal 100 was an example of the structure which is what is called a smart phone. However, the mobile terminal 100 does not necessarily need to be a so-called smartphone as long as the mobile terminal 100 includes a film speaker that behaves as a capacitive load and has a function that realizes a process equivalent to the cutoff frequency control process. As an example, with a tablet computer, PDA (Personal Digital Assistant), foldable mobile phone, etc., which has a film speaker that behaves as a capacitive load and has a function that realizes a process equivalent to the cut-off frequency control process. An example can be considered.

  (8) In Modification 3, the mobile terminal of the third modification has a function in which the user operation reception unit 1520 receives a genre designation by the user, and the music to be played is a genre designated by the user. In some cases, the constant variable low-pass filter unit 670 is set to have no cutoff even when the remaining amount of the battery 555 is equal to or less than a predetermined amount. On the other hand, as another example, the user operation accepting unit 1520 has a function of accepting designation of music by the user, and when the music to be played is music designated by the user, the remaining amount of the battery 555 is low. An example of a configuration in which the constant variable low-pass filter unit 670 is set without a cut-off even if it is equal to or less than a predetermined amount can be considered.

  (9) The above embodiment and the above modifications may be combined as appropriate.

  The portable terminal and the control method thereof according to the present invention can be widely used for portable terminals including a film speaker that behaves as a capacitive load.

DESCRIPTION OF SYMBOLS 100 Portable terminal 200a Film speaker 200b Film speaker 610 Control part 615 Predetermined amount memory | storage part 620 User operation reception part 625 Notification instruction | indication reception part 630 Remaining amount measurement part 635 Reproduction | regeneration table memory | storage part 640 Information table memory | storage part 650 Sound source memory | storage table memory Unit 655 sound source reading unit 660 decoding unit 665 buffer unit 670 constant variable low-pass filter unit

Claims (10)

A portable terminal that operates using electric power stored in a built-in battery,
A storage unit for storing an audio signal;
A low-pass filter section that cuts a high-frequency band during reproduction of the audio signal stored by the storage section;
A film speaker that acts as a capacitive load that outputs audio based on the audio signal whose high frequency band has been cut by the low-pass filter unit,
A measurement unit that measures the remaining amount of power stored in the battery,
The low-pass filter unit has a cutoff frequency when the remaining amount is less than a predetermined amount, according to the remaining amount of power measured by the measuring unit, when the remaining amount is greater than the predetermined amount. The mobile terminal, wherein the high frequency band is cut so as to be lower than a cutoff frequency. The low-pass filter unit sets the cutoff frequency as the first frequency when the remaining amount of power measured by the measuring unit is larger than the predetermined amount, and sets the cutoff frequency when the remaining amount is smaller than the predetermined amount. The mobile terminal according to claim 1, wherein the high frequency band is cut so that the second frequency is lower than the first frequency. When the sound to be output from the film speaker includes one or more music pieces, the low-pass filter unit is configured such that the remaining amount of power measured by the measurement unit decreases across the predetermined amount. Even so, switching of the cut-off frequency from the first frequency to the second frequency is suppressed during a period in which the film speaker outputs one piece of music. A music type designation unit that accepts designation of the type of music by the user,
The low-pass filter unit outputs the type of music accepted by the music type designation unit even when the remaining amount of power measured by the measurement unit is smaller than the predetermined amount. The mobile terminal according to claim 3, wherein the period is set to the first frequency instead of the cut-off frequency as the second frequency. It has a music specification unit that accepts music specification by the user,
Even when the remaining amount of power measured by the measurement unit is smaller than the predetermined amount, the low-pass filter unit has a period in which the film speaker outputs the music received by the music designating unit, The mobile terminal according to claim 3, wherein the cutoff frequency is not the second frequency but the first frequency. A determination unit that determines whether or not the sound to be output by the film speaker is a notification sound;
The low-pass filter unit is configured to output the sound determined by the determination unit not to be the notification sound even when the remaining amount of power measured by the measurement unit is smaller than the predetermined amount. The portable terminal according to claim 3, wherein the output period is the first frequency without the cut-off frequency being the second frequency. The low-pass filter unit is
Digital low-pass filter with programmable cutoff frequency,
When the remaining amount of power measured by the measuring unit is larger than the predetermined amount, the cutoff frequency of the low-pass filter unit becomes the first frequency, and the remaining amount of power measured by the measuring unit is the predetermined amount. The mobile unit according to claim 2, further comprising a setting unit configured to set a cutoff frequency of the digital low-pass filter so that a cutoff frequency of the low-pass filter unit becomes the second frequency when the frequency is smaller. Terminal. An amplifier that amplifies an audio signal from which a high-frequency component has been cut by the low-pass filter unit,
The portable terminal according to claim 7, wherein the film speaker outputs the sound by converting the sound signal amplified by the amplifier into sound. A portable terminal that operates using electric power stored in a built-in battery,
A storage unit for storing an audio signal;
A low-pass filter section that cuts a high-frequency band during reproduction of the audio signal stored by the storage section;
A film speaker that acts as a capacitive load that outputs audio based on the audio signal whose high frequency band has been cut by the low-pass filter unit,
A measurement unit that measures the remaining amount of power stored in the battery,
The low-pass filter unit cuts the high-frequency band according to the remaining amount of power measured by the measurement unit when the remaining amount is less than a predetermined amount. A mobile terminal control method that includes a storage unit that stores an audio signal, a film speaker that behaves as a capacitive load, a low-pass filter unit, and a measurement unit, and that operates using power stored in a built-in battery. There,
The measurement unit measures the remaining amount of power stored in the battery,
In the case where the low-pass filter unit has a cutoff frequency when the remaining amount is smaller than the predetermined amount, according to the remaining amount of power measured by the measuring unit, the remaining amount is larger than the predetermined amount. Cut the high frequency band at the time of reproduction of the audio signal stored by the storage unit so as to be lower than the cutoff frequency,
The control method, wherein the film speaker outputs a sound to the outside based on a sound signal in which a high frequency region is cut by the low-pass filter unit.

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