JP4037595B2 - Audio signal output level switching system, personal computer and recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an audio signal output level switching system, a personal computer, and a recording medium, and more particularly to an audio signal output level for switching an output level of an audio signal to be output to a headphone output level and a line output level. The present invention relates to a switching method, a personal computer, and a recording medium.
[0002]
[Prior art]
In general, in an audio signal output interface unit such as a personal computer, a line output terminal and a headphone output terminal are provided separately. With the recent demand for downsizing and cost reduction of personal computers, the line output terminal and the headphone output terminal may be used together.
[0003]
However, since the line output level is different from the headphone output level, the user has to adjust the volume with the output adjustment volume according to the type of the external device connected to the output terminal.
[0004]
In addition, since the output level cannot be switched, the level may be insufficient when using headphones, or the output may be maximized when using line-out, which may adversely affect audio equipment.
[0005]
Therefore, for example, in Japanese Patent Laid-Open No. 9-231050, a resistor is connected in series between an output connector connected to an external device such as a headphone or an audio amplifier and an amplifier circuit that amplifies a predetermined audio signal. A notebook personal computer has been proposed.
[0006]
According to this conventional technique, the output voltage varies depending on the external device connected to the output terminal due to the voltage dividing action between the resistor and the input impedance of the external device. The effort to adjust the volume can be omitted.
[0007]
[Problems to be solved by the invention]
However, in this prior art, when the audio amplifier is connected to the output terminal, the output voltage does not decrease so much, and when the headphones are connected to the output terminal, the resistance value that greatly decreases the output voltage is set. Only the resistor having the above is provided, and the output level adjustment is considerably rough. Therefore, with this conventional technique, it is difficult to adjust to the optimum output level according to the external device, and it can be said that the user can omit the trouble of adjusting the volume according to the type of the external device. Absent.
[0008]
The present invention has been made to solve the above-described problems, and provides an output level switching method for audio signals, a personal computer, and a recording medium that can be switched to an optimum output level according to the connected external device. For the purpose.
[0009]
[Means for Solving the Problems]
The first audio signal output level switching system of the present invention includes a plurality of amplification means for amplifying an audio signal to a plurality of different levels, a selection signal generation means for generating a selection signal, and a selection generated by the selection signal generation means. Selection means for selecting one amplifying means from a plurality of amplifying means by inputting a signal, and outputting an audio signal amplified by the selected amplifying means, and display means for displaying which amplifying means is selected It is characterized by having.
[0010]
The second output level switching system for audio signals of the present invention comprises a first amplifying means for amplifying an audio signal to a headphone output level, a second amplifying means for amplifying the audio signal to a line output level, and a selection. A selection signal generation means for generating a signal, and an input of the selection signal generated by the selection signal generation means selects one of the first amplification means and the second amplification means, and the selected amplification means And a selection means for outputting the amplified audio signal and a display means for displaying which amplification means is selected.
[0011]
The selection signal generation means may include a changeover switch for switching a signal level of the selection signal.
[0012]
The display means may input a selection signal generated by the selection signal generation means and display which amplification means is selected.
[0013]
The display means is, for example, an LED.
[0014]
The selection signal generating means may be a slide type switch, and the display means may include a display unit whose display changes according to the movement position of the slide type switch.
[0015]
The display means is a computer monitor, for example.
[0016]
The personal computer according to the present invention includes an audio signal generating means for generating an audio signal and an output terminal for outputting the audio signal, wherein the audio signal generated by the audio signal generating means is output for the audio signal. The output level is switched using a level switching method and output from the output terminal.
[0017]
According to the first recording medium of the present invention, one amplification unit is selected from the plurality of amplification units by a process of amplifying the audio signal to a plurality of different levels by the amplification unit and the selection signal generated by the selection signal generation unit. A program for causing a computer to execute a process for selecting and outputting an audio signal amplified by the selected amplification means and a process for displaying on the display means which amplification means has been selected is recorded. It is a feature.
[0018]
The second recording medium of the present invention includes a process for amplifying an audio signal to the headphone output level by the first amplifying means, a process for amplifying the audio signal to the line output level by the second amplifying means, and a selection signal. A process of selecting any one of the first amplifying means and the second amplifying means by inputting the selection signal generated by the generating means, and outputting the audio signal amplified by the selected amplifying means; A program for causing a computer to execute processing for displaying on the display means which amplification means has been selected is recorded.
[0019]
According to the present invention, audio signals of different output levels can be exclusively selected and output from one shared output terminal. In addition, the output level can be switched to an optimum level according to the external device connected to the output terminal. Further, since the display means for displaying which amplification means is selected is provided, the output level of the audio signal output from the selection means controlled by the selection signal can be easily determined from the outside.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of the first embodiment of the present invention, FIG. 2A is a block diagram showing a selection signal generator and an indicator, and FIG. 1B is a circuit showing an example of a circuit configuration of a selector. FIG.
[0021]
As shown in FIG. 1, the personal computer 1 according to the first embodiment of the present invention includes an audio LSI 2 that performs audio reproduction under the control of the CPU, and an analog audio signal S1 output from the audio LSI 2. The D / A converter 3 for converting to the audio signal S2, the audio signal output level switching processing unit 4 for switching the output level of the audio signal, and the audio signal output from the audio signal output level switching processing unit 4 are output to the outside. Output terminal 5. An external device such as a headphone or an audio amplifier is connected to the output terminal 5.
[0022]
The main body of the personal computer 1 includes a CPU, ROM, RAM, and the like, and is connected to an input device such as a keyboard and a mouse, an output device such as a monitor (display) and a printer, and an external storage device such as a hard disk. (Not shown).
[0023]
The audio signal output level switching processing unit 4 generates a first amplifier 6 that amplifies the audio signal to the headphone output level, a second amplifier 7 that amplifies the audio signal to the line output level, and a selection signal S3. The selection signal generation unit 8 to be selected and the selection signal S3 generated by the selection signal generation unit 8 to select one of the first amplifier 6 and the second amplifier 7 and amplify by the selected amplifier A selector unit 9 that outputs the audio signal and an indicator unit 10 that displays which amplifier is selected.
[0024]
For example, as shown in FIG. 2A, the selection signal generator 8 has a change-over switch 11 for changing the signal level of the selection signal S3, and one end of the change-over switch 11 is connected to a power source V via a resistor R. And the other end is grounded.
[0025]
The selector unit 9 controls selection of whether to output the audio signal amplified by the first amplifier 6 or to output the audio signal amplified by the second amplifier 7 by the input selection signal S3, Perform exclusive switching. The selector unit 9 includes an n-channel MOS transistor 12 connected to the first amplifier 6 and a p-channel MOS transistor 13 connected to the second amplifier 7 as shown in FIG. 2B, for example. The output terminal 5 is connected between the n-channel MOS transistor 12 and the p-channel MOS transistor 13. The selection signal S3 is input to the gates of the n-channel MOS transistor 12 and the p-channel MOS transistor 13, and the n-channel MOS transistor 12 and the p-channel MOS transistor 13 are switched on and off. The selector unit 9 is not limited to the circuit configuration described above.
[0026]
The indicator unit 10 has a role of displaying which of the outputs of the first amplifier 6 and the second amplifier 7 is effective to the outside. For example, as shown in FIG. 2A, the indicator unit 10 displays that the first LED 14 that indicates that the first amplifier 6 is selected and the second amplifier 7 is selected. 2 LEDs 15. An inverter (NOT circuit) 16 is connected to the front stage of the second LED 15.
[0027]
Next, the operation of the first embodiment will be described.
[0028]
A digital audio signal S1 output from the audio LSI 2 under the control of the CPU of the personal computer 1 is converted into an analog audio signal S2 by the D / A converter 3. The audio signal S2 converted by the D / A converter 3 is input to the first amplifier 6 and the second amplifier 7, respectively. The first amplifier 6 is adjusted to the headphone out output level, and the second amplifier 7 is adjusted to the line out output level.
[0029]
On the other hand, the signal level of the selection signal S3 is selected by the selector switch 11 of the selection signal generator 8. The selection signal S3 is input to the gates of the n-channel MOS transistor 12 and the p-channel MOS transistor 13 of the selector unit 9, respectively.
[0030]
When the signal level of the selection signal S3 is HIGH, the n-channel MOS transistor 12 of the selector unit 9 is turned on, so that the audio signal amplified to the headphone output level by the first amplifier 6 is output from the output terminal 5 Is done.
[0031]
When the signal level of the selection signal S3 is LOW, the p-channel MOS transistor of the selector unit 9 is turned on, so that the audio signal amplified to the line output level by the second amplifier 7 is output from the output terminal 5. The
[0032]
The selection signal S3 is input to the indicator unit 10. When the signal level of the selection signal S3 is HIGH, the first LED 14 is lit, so that the first amplifier 6 is selected and the audio signal amplified to the headphone output level is output from the output terminal 5. I understand that.
[0033]
When the signal level of the selection signal S3 is LOW, the second LED 15 is lit, so that the audio signal amplified by the second amplifier 7 and amplified to the line output level is output from the output terminal 5. I understand that.
[0034]
The user connects headphones or the like to the output terminal 5 when the first LED 14 is lit, and connects an audio amplifier or the like to the output terminal 5 when the second LED 15 is lit. become.
[0035]
According to the first embodiment, since audio signals having different output levels can be exclusively selected and output from one shared output terminal 5, the number of output terminals 5 is reduced, and personal signals are reduced. The computer 1 can be reduced in size and cost.
[0036]
In addition, the output level can be switched to an optimum level according to the external device connected to the output terminal 5.
[0037]
Furthermore, since the indicator unit 10 for displaying which amplifier is selected is provided, the output level of the audio signal output from the selector unit 9 controlled by the selection signal S3 can be easily determined from the outside. .
[0038]
FIG. 3 is a block diagram showing a second embodiment of the present invention. The second embodiment is characterized in that only one LED 17 is used as the indicator unit 10. When the signal level of the selection signal S3 is HIGH, the LED 17 is lit, so that it can be understood that the audio signal amplified by the first amplifier 6 and amplified to the headphone output level is output from the output terminal 5. .
[0039]
When the signal level of the selection signal S3 is LOW, since the LED 17 is not lit, the second amplifier 7 is selected and the audio signal amplified to the line output level is output from the output terminal 5. I understand.
[0040]
According to the second embodiment, since the display function of the indicator unit 10 can be satisfied by one LED 17, the configuration becomes simpler, and the personal computer 1 can be further reduced in size and cost.
[0041]
4 (A) and 4 (B) are explanatory views showing a third embodiment of the present invention. The third embodiment is characterized in that a slide switch 18 is used as the changeover switch 11.
[0042]
As shown in FIGS. 4A and 4B, when the moving position of the sliding switch 18 is switched up and down, the color of the display unit 19 changes, and it is easy to determine which output level is selected. Can do. The display unit 19 may be configured to display with characters and symbols instead of colors.
[0043]
According to the third embodiment, since the changeover switch 11 itself has a function as the indicator unit 10, it is not necessary to separately provide the indicator unit 10, and the configuration is simplified and the cost is reduced. be able to.
[0044]
FIG. 5 is a block diagram showing a fourth embodiment of the present invention. The fourth embodiment is characterized in that a computer monitor 20 is applied as display means.
[0045]
As shown in FIG. 5, the selection signal S3 is input to the CPU 21 of the personal computer 1, and the control signal output from the CPU 21 is input to the accelerator 22 that controls the image processing of the monitor 20. The monitor 20 displays on the screen which output level is selected according to the signal level of the selection signal S3.
[0046]
According to the fourth embodiment, the function of the indicator unit 10 can be given to the monitor 20 by displaying the selected output level on the screen of the monitor 20 with characters or pictures.
[0047]
FIG. 6 is a block diagram showing the configuration of the fifth embodiment of the present invention. The fifth embodiment has a recording medium 23 that records a program (audio signal output level switching processing program) for causing a computer to execute the above-described audio signal output level switching processing. Is. The recording medium 23 may be a magnetic disk, a CD-ROM, a semiconductor memory, or other recording medium.
[0048]
The audio signal output level switching processing program is read from the recording medium 23 into the audio signal output level switching processing unit 4 and controls the operation of the audio signal output level switching processing unit 4 described above.
[0049]
The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical matters described in the claims. For example, in the above embodiment, two output levels of the output level for headphones and the output level for lines are selected for the audio signal. However, the present invention is not limited to this, and other output levels may be selected. Good. In addition, one amplifying unit may be selected from a plurality of three or more amplifying units (amplifiers), and the audio signal amplified by the selected amplifying unit may be output from the output terminal 5.
[0050]
Further, the configuration of the selection signal generation unit 8, the selector unit 9, and the indicator unit 10 is not limited to that of the above embodiment.
[0051]
【The invention's effect】
According to the present invention, audio signals of different output levels can be exclusively selected and output from one shared output terminal, so that the number of output terminals is reduced, and the personal computer can be reduced in size and cost. You can go down.
[0052]
In addition, the output level can be switched to an optimum level according to the external device connected to the output terminal.
[0053]
Further, since the display means for displaying which amplification means is selected is provided, the output level of the audio signal output from the selection means controlled by the selection signal can be easily determined from the outside.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a first embodiment of the present invention.
FIG. 2A is a block diagram illustrating a selection signal generation unit and an indicator unit, and FIG. 2B is a circuit diagram illustrating an example of a circuit configuration of a selector unit.
FIG. 3 is a block diagram showing a second embodiment of the present invention.
4A and 4B are explanatory diagrams showing a third embodiment of the present invention. FIG.
FIG. 5 is a block diagram showing a fourth embodiment of the present invention.
FIG. 6 is a block diagram showing a configuration of a fifth embodiment of the present invention.
[Explanation of symbols]
S1: Digital audio signal S2: Analog audio signal S3: Selection signal 1: Personal computer 2: Audio LSI
3: D / A converter 4: Audio signal output level switching processing unit 5: Output terminal 6: First amplifier 7: Second amplifier 8: Selection signal generating unit 9: Selector unit 10: Indicator unit 11: Changeover switch 12: n-channel MOS transistor 13: p-channel MOS transistor 14: first LED
15: Second LED
16: Inverter (NOT circuit)
17: LED
18: Slide type switch 19: Display unit 20: Monitor 21: CPU
22: Accelerator 23: Recording medium

Claims (9)

A plurality of amplification means for amplifying the audio signal to a plurality of different levels;
Selection signal generating means for generating a selection signal;
A selecting means for selecting one amplifying means from among a plurality of amplifying means by inputting a selection signal generated by the selecting signal generating means, and outputting an audio signal amplified by the selected amplifying means;
Display means for displaying which amplification means is selected based on the selection signal ;
An output level switching system for audio signals, comprising: First amplification means for amplifying the audio signal to an output level for headphones;
Second amplifying means for amplifying the audio signal to the line output level;
Selection signal generating means for generating a selection signal;
Selection of selecting one of the first amplification means and the second amplification means by the selection signal generated by the selection signal generation means and outputting the amplified audio signal to the selected amplification means Means,
Display means for displaying which amplification means is selected based on the selection signal ;
An output level switching system for audio signals, comprising:   3. The audio signal output level switching system according to claim 1, wherein the selection signal generating means includes a selector switch for switching a signal level of the selection signal. The audio signal output level switching system according to any one of claims 1 to 3 , wherein the display means is an LED. The selection signal generating means is a slide switch,
The display means includes a display unit whose display changes according to the movement position of the slide switch.
The audio signal output level switching method according to any one of claims 1 to 3 . The display means, the audio signal output level switching method according to any one of claims 1 to 3, characterized in that a monitor of the computer. In a personal computer comprising audio signal generating means for generating an audio signal and an output terminal for outputting the audio signal,
The audio signal generated by the audio signal generating means is output from the output terminal by switching the output level using the audio signal output level switching method according to any one of claims 1 to 6. A featured personal computer. A process of amplifying the audio signal to a plurality of different levels by an amplification means;
A process of selecting one amplifying means from among a plurality of amplifying means by inputting a selection signal generated by the selecting signal generating means, and outputting an audio signal amplified by the selected amplifying means;
A process of displaying on the display means which amplification means has been selected based on the selection signal ;
A recording medium on which a program for causing a computer to execute is recorded. A process of amplifying the audio signal to an output level for headphones by a first amplifying means;
A process of amplifying the audio signal to a line output level by a second amplifying means;
Processing for selecting one of the first amplifying means and the second amplifying means by inputting the selection signal generated by the selection signal generating means, and outputting the audio signal amplified by the selected amplifying means When,
A process of displaying on the display means which amplification means has been selected based on the selection signal ;
A recording medium on which a program for causing a computer to execute is recorded.

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