JPH0537532Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to a volume adjustment circuit using an electronic volume suitable for application to various audio equipment.

``Prior Art'' In volume adjustment circuits used in audio equipment, video equipment, etc., as well-known volume mechanisms for adjusting volume, analog or mechanical systems and volume ICs are used. An electronic volume type is known.

In analog systems, the volume is generally adjusted using a rotary or sliding volume knob. Therefore, even when power is not supplied to the audio equipment, there is an advantage that the rough volume of the sound to be emitted when the power is turned on next time can be determined visually based on the rotational position of the volume knob.

On the other hand, the electronic volume type, which uses a volume IC and uses a microcomputer to control the amount of attenuation of this IC, has features such as being able to be controlled remotely using a remote control.

``Problems to be solved by the invention'' By the way, when an electronic volume is used as a volume control device, LEDs or LCDs are generally used to display the volume level.

In this case, when the main power of the device is turned off, the LED
and LCD power will also be turned off at the same time. Therefore,
Unlike the analog type, there is a drawback that it is not possible to visually confirm the rough volume of the sound emitted when the power is turned on next time.

Therefore, for example, if the power is turned off while the device is being used at a high volume, it has the disadvantage that when the power is turned on again, the music is suddenly played back at a high volume.

Therefore, in this invention, such conventional problems are solved with a simple structure, and in particular, only the volume level control means and display means for controlling and displaying the volume level are supplied with power via the sub-power supply unit. We propose a volume adjustment circuit that can adjust the volume of an electronic volume when in standby mode.

"Means for Solving the Problems" In order to solve the above problems, this invention provides a main power supply that supplies power to the entire device, and a volume level control means and display means that control and display at least the volume level. and a sub-power source for supplying power, and when in standby mode in which power is supplied to the volume level control means and display means only through the sub-power source, the volume of the electronic volume can be adjusted. This is a characteristic feature.

"Operation" In this invention, at least the control means 20 and the display means 22 for controlling and displaying the volume level.
However, in addition to the main power supply section, it has a sub power supply section that is separate from other circuit systems. If the mode in which power is supplied to the volume level control means 20 and the display means 22 via the sub power supply unit 38 is set to standby mode, the electronic volume can be adjusted in volume in this standby mode.

In standby mode, the volume level control means 20
Power is supplied to the display means 22 via the sub-power supply section 38, and the volume state can be visually determined, so if you want to lower the volume level, you can use the volume adjustment control for the electronic volume. Just supply the signal.

This is normally done using an up/down key for volume adjustment provided on the main unit or remote control.

By providing such a standby mode, the volume level can be visually checked and the volume can be adjusted, so that the disadvantage of emitting sound at an excessive volume by canceling the standby mode can be eliminated.

"Embodiment" Next, an example of the volume adjustment circuit according to the invention will be described in detail with reference to FIG. 1 and subsequent figures.

FIG. 1 is a system diagram showing an example of a case where a volume adjustment circuit 10 according to the present invention is applied to a radio receiver.

In the figure, a playback signal supplied to a terminal 1 is supplied to a speaker 6 via an electronic volume 3, a muting circuit 4 and a power amplifier 5, and the signal is reproduced at a volume adjusted by the electronic volume 3.

As an example, a case will be described below in which the control means 20 is composed of a one-chip microcomputer.

First, the CPU 11 is a central processing unit for controlling controls corresponding to various operation keys and other controls. This CPU 11 receives data from a ROM 12 in which a control program is stored, and is associated with a RAM 13 having a predetermined memory capacity.

Further, the CPU 11 is configured to receive input states of a plurality of keys provided on the operation display section. The figure shows typical input keys (switches).

14 is a main power switch (main switch). 15 is an up-down key for adjusting the volume, and 16 is a sub-switch used when operating the sub-power supply section.

Key input from these is to which I/O port 1?
7 to 19, the data is taken into the CPU 11 and a corresponding control signal is generated.

The command signal from the CPU 11 is further supplied to the muting circuit 4 via the I/O port 24 to perform muting control. That is, the muting circuit 4 operates at necessary functions, such as when the power is turned on or when switching channels, to prevent unnecessary signals from being emitted. Normally, in order to eliminate the pop noise that occurs when the power is turned on, the
This muting circuit 4 is controlled to operate.

Now, in this invention, at least the control means 20 and the display means 22 for controlling and displaying the volume level have, in addition to the main power supply section 36, a sub-power supply section 38 that is separate from the other circuit systems.

Volume level control means 2 via sub power supply section 38
The mode in which power is supplied to 0 and the display means 22 is hereinafter referred to as standby mode.

This standby mode can be controlled either on the receiver main body side or on the remote control side. In the following description, a case will be exemplified in which the standby mode is controlled on the remote control side.

Therefore, as shown in FIG. 1, based on the command signal from the CPU 11, the
The display state of the volume level display means 22 such as an LCD is controlled. The display means 22 has the function of displaying at least the volume level as described above, but in addition to this function of displaying the volume level, it may also have a frequency display or a channel display, for example.

Furthermore, the command signal from this CPU 11 is
The signal is supplied to the main power supply unit 36 via the O port 35 as its power control signal. The main power supply section 36 supplies power to the entire device, and therefore also supplies power to other circuit systems (not shown). Further, a control signal received from the remote control side is received by the receiving element 31, and this received signal is taken into the CPU 11 via the remote control receiving section 32 and the I/O port 33. As a result, control is executed according to the content of the remote control signal. Also,
A command signal from the CPU 11 is supplied as a control signal to the sub power supply section 38 via the I/O port 37. This sub power supply section 38 supplies power to the volume level control means 20 and the display means 22 only in standby mode.

In normal use, power is supplied to the entire device via the main power supply section 36 by operating the main switch 14, and at this time, the sub power supply section 38 supplies power to the volume level control means 20 and the display means 22. Power is not supplied.

Next, for example, when a standby mode is selected in which power is supplied to only the control means 20 and display means 22 as described above from a state in which power is supplied to the entire device via the main power supply section 36, A power-off control signal is supplied to the main power supply section 36, a power-on control signal is supplied to the sub-power supply section 38, and only the volume level control means 20 and the display means 22 are in operation in the main body of the device.

Selection of the standby mode is operated by a remote control switch provided on the remote control side or a sub switch 16 for the sub power supply section 38.

Even in the standby mode, the control means 20 including the CPU 11 and the display means 22 are backed up by the auxiliary power supply section 38, so this control system remains in an operating state. In this invention, the electronic volume 3 can be adjusted during standby mode.

In this case, the volume can be adjusted visually.

FIG. 2 shows an example of a control routine 40 for setting values for adjusting the volume (volume adjustment value) during this standby mode.

First, by turning off the power switch provided on the remote control side or by turning off the sub switch 16, the power supply state to the main power supply section 36 is cut off as described above. Then, only the display means 22 becomes operational. The display means 22 maintains the display state (step 41).

At the same time as the power switch is turned off, a volume adjustment value (hereinafter referred to as a set value) M1 for the electronic volume 3 is stored in the RAM 13 (step 42).

Even in this power switch-off state, up-down key input for volume adjustment is accepted. As a result, the input state of the up-down key is checked (step 43), and when the up-down key is not operated, the new setting value M2 stored in the RAM 13 is changed to the already stored setting value M1.
That is what it is. On the other hand, when the up/down key is operated, the setting value M2 for the electronic volume 3 is changed depending on the up or down direction. The new set value M2 after the change is stored in memory (steps 44 and 45).

With the operation of the up-down key, the new setting value is changed to M2, but at the same time as the key operation, a control signal corresponding to the changed setting value M2 is supplied from the CPU 11 to the display means 22. The display means 22 will display the volume level corresponding to the new set value M2 (step 46). Therefore, the user can adjust the volume level to the optimum level for the next time he/she wishes to listen while looking at the display means 22.

Next, wait for the power switch on the remote control to be turned on again (step 47).

When the main power supply 36 is turned on, the set value for the electronic volume 3 is first controlled to be -∞ (step 48).

This is to eliminate pop noise that occurs when the power is turned on. Since the muting circuit 4 is normally operated at the same time as the power is turned on, this structure prevents pop noise from occurring in both the muting circuit 4 and the electronic volume 3.

Therefore, it is also possible to omit the muting circuit 4 and remove pop noise using only the electronic volume 3.

Next, set the setting value for electronic volume 3 to −∞
At the same time, the time since the main power was turned on is measured, and in this example, it is checked whether one second has elapsed (step 49).

If it is less than 1 second, the process returns to step 48 and the set value for the electronic volume 3 is set to -∞.

When one second has elapsed, the new setting value M2 set in step 45 is output as the setting value to be supplied to the electronic volume 3 (step 50). As a result, electronic volume 3 changes to the new setting value M2.
The sound will be emitted at a volume corresponding to the set value.

As a result, it is possible to eliminate the problem of suddenly emitting excessive volume when the power is turned on again.

In addition, in the above description, the standby mode was realized by the remote control switch provided on the remote control side, but if the sub switch 16 (standby switch) that controls only the main power supply is provided on the receiver body side, this mode can be realized. By operating the standby switch, it is possible to select a mode in which only the above-mentioned volume level control means 20 and display means 22 are supplied with power, and the volume can be adjusted visually.

In addition, in this invention, the main power supply section and the sub power supply section are configured as separate power supply sections, but the point is that it is sufficient to control the power supply so that power is supplied only to at least the control means and the display means during standby mode. , the main power supply section can also be used as a sub power supply section.

"Effect of the invention" As explained above, according to this invention, at least the control means and display means for controlling and displaying the volume level have a sub-power supply section separate from other circuit systems in addition to the main power supply. In particular, when a standby mode is selected in which power is supplied to at least the volume level control means and the display means through the sub-power supply section, the electronic volume can be adjusted while visually checking the volume level. be.

According to this, even in standby mode,
The volume level is displayed on the display means via the auxiliary power supply section. As a result, if the volume level for the next time you want to listen is too high, you can change it to the optimal volume level while visually checking by operating the volume adjustment up-down key.

That is, it has the practical benefit of being able to adjust the volume level without turning on the power switch again. This eliminates the problem of suddenly emitting sound at an excessive volume when the power is turned on.

Further, in cases where the receiver body is equipped with a timer function, the volume can be adjusted even if the receiver is set to turn on the next morning. In this case, there is no need to operate the timer set key again to cancel standby mode.

Therefore, the volume adjustment circuit using the electronic volume according to this invention is extremely suitable for application to audio equipment such as the above-mentioned audio equipment and video equipment.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an example of a volume adjustment circuit according to the invention, and FIG. 2 is a flowchart showing an example of a set value control routine for an electronic volume. 3...Electronic volume, 4...Mute circuit, 10...Volume adjustment circuit, 11...CPU, 1
3...RAM, 16...Sub switch, 22...
Display means for LCD, 32...Remote control receiver, 3
6... Main power supply section, 38... Sub-power supply section.

Claims (1)

[Claims for Utility Model Registration] A main power supply for supplying power to the entire device, and a sub-power supply for supplying power to at least a volume level control means and a display means for controlling and displaying the volume level, the volume level 1. A volume adjustment circuit, characterized in that the electronic volume can be adjusted in a standby mode in which power is supplied to the control means and the display means only through the auxiliary power source.