JPS6375592A - Power source controller by timer of audio device - Google Patents

Abstract

PURPOSE:To prevent a user from feeling uncomfortable by turning off the power source of an audio device after fading out a sound from a speaker when the audio device is powered off by the sleep function of a timer. CONSTITUTION:A timer circuit 10 outputs a time detection signal 10a at time set with a timer switch 12. The voltage level of an input signal 2a is compared by a level detecting circuit 7 with a reference level and a level detection signal 7a is outputted when the voltage level is lower than the reference level. A control circuit 9 outputs a fading control signal 9b unless the signal 7a is inputted within a constant time after the input time of the signal 10a to drive the motor 3a of a fading circuit 3, thereby fading out a signal 3c supplied to an amplifying circuit 4. Then a power source control signal 9a is outputted to turn off power switches 6 and 8, and the audio device is powered off. Therefore, the power source is never turned off at the climax, etc., of music, so the user does not feel uncomfortable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a timer-based power supply control device for an audio device, and particularly to a timer-based power supply control device for an audio device suitable for a sleeve function.

[Conventional technology]

The power control device using a timer for conventional audio equipment is
For example, Japanese Patent Publication No. 54-44590, Japanese Patent Publication No. 54-44590,
As disclosed in Japanese Patent No. 42579, when the set time of the timer is reached, the power of the device to be controlled is simply turned on or off to emit or stop the audio demodulated signal (hereinafter simply referred to as the audio signal). It was only to control.

That is, conventionally, when turning off the power of an audio device using a timer, no particular consideration was given to the magnitude of the audio signal level.

[Problems to be Solved by the Invention] Therefore, in the above-mentioned prior art, if the audio signal level is high when the audio device is turned off, it may cause discomfort to the user who is trying to fall asleep, for example. There was a problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide a timer for an audio device that does not abruptly turn off the power of the audio device when the audio signal level is high, and therefore does not cause discomfort to the user. An object of the present invention is to provide a power supply control device according to the present invention.

[Means for solving problems]

The above purpose is to detect the audio signal level after the timer setting time, and if a silent interval is detected, turn off the power during this interval, and if no silent interval is detected, the audio signal level This is achieved by gradually reducing the power and then turning off the power.

[Effect]

The timer outputs a time detection signal when the set time comes. Further, the audio signal level is compared with a certain reference level by a level detection circuit, and when the audio signal level is below the reference level, the level detection circuit outputs a level detection signal. The present invention turns off the power of the audio device based on the level detection signal if the level detection signal is obtained within a certain period of time after the time detection signal is obtained. Also, if a level detection signal is not obtained within a certain period of time,
Turn off the power after gradually reducing the audio signal level.

As a result, according to the present invention, the power is not suddenly turned off when the audio signal level is high, and therefore the user does not feel uncomfortable.

〔Example〕

Hereinafter, the present invention will be explained using the drawings. FIG. 1 is a block diagram showing one embodiment of the present invention.

In FIG. 1, 1 is a tuner circuit connected to a signal input terminal 2, 3 is a fader circuit composed of a motor 3a and a volume 3b that moves in conjunction with the motor 3a, 4 is an amplifier circuit, and 5 is an amplifier circuit. a speaker driven by 4;
6 is a power switch that turns on or off the power of the tuner circuit 1; 4; 7 is a level detection circuit that detects the voltage level of the signal 2a input to the signal input terminal 2; 10 is a timer switch 12; A timer circuit 8 is an amplifier circuit 4 in which the time is set.
A power switch 9 turns on or off the power switches 6 and 8, and controls the on/off of the power switches 6 and 8.
A control circuit controls the fader circuit 5, and 11 is a power input line.

Here, the operations of the level detection circuit 7, timer circuit 10, and control circuit 9 shown in FIG. 1 will be explained.

The level detection circuit 7 detects the signal 2 input to the signal input terminal 2.
When the signal level of a falls below a predetermined level, a level detection signal 7a is output.

The timer circuit 10 outputs a time detection signal 10a when the time set by the timer switch 12 is detected.

When the level detection signal 7a is output at time t2 within a predetermined first time T1 from the output time t1, the power supply control signal 9a is output at the time t2, and the power switches 6 and 8 are turned on. Turn off the power to the Chu6 circuit 1 and the amplifier circuit 4. Furthermore, if the level detection signal 7a is not output by time t3 when a predetermined first time T1 has elapsed from time t1 when the time detection signal 10a is output, the control circuit 9 outputs a fade control signal 9b. is output, the motor 3a of the fader circuit 6 is driven, and the signal level of the signal 6C supplied to the amplifier circuit 4 is gradually lowered. Then, from time 5, the power supply control signal 9a is activated when a predetermined second time T2 has elapsed.
is output, power switches 6 and 8 are turned off, and the tuner circuit 1 and amplifier circuit 4 are turned off.

The operation of this embodiment will be explained below using FIGS. 2 and 3.
This will be explained in more detail. In these figures, the same reference numerals as in FIG. 1 indicate signal waveforms at the corresponding reference numerals in FIG. However, 6.8 is the power switch 6 in Figure 1.
and 8 states.

First, the case where the level detection signal 7a is detected within the first time T1 will be explained using FIG. 2.

Timer circuit 1 at time t1 set by timer switch 12.
When the time detection signal 10a is output from 0, the control circuit 9
is a predetermined first time T from the time t1
When the level detection signal 7a is supplied within 1, the power supply control signal 9a is output.

In FIG. 2, a signal 2a is input from the Chu6 circuit 1 via the signal input terminal 2 at time t2 within the first time T1.
Since the level of t2 decreases, the level detection circuit 7 outputs the level detection signal 7a at the time t2. As a result, the control circuit 9 outputs the power supply control signal 9a at time t2. Therefore, power switches 6 and 8 are turned on (ON).
) to OFF, and the power to the Chu6 circuit 1 and the amplifier circuit 4 is turned off. For this reason, the output signal 4a of the amplifier circuit 4 is no longer output after time t2.

That is, in the case of FIG. 2, the power is turned off during the silent section of the input signal 2a.

Next, a case where the level detection circuit 7a is not detected within the first time T1 will be explained using FIG. 3.

As explained with reference to FIG. 2, the time detection signal 10a is output from the timer circuit 10 at time t1, but the third
In the figure, by time t3 when a predetermined first time T1 has elapsed from time t1, the level detection signal 7 is output from the level detection circuit 7 in order to prevent the level of the input signal 2a from decreasing.
a is not output. Therefore, the control circuit 9 controls the time t3.
to time t4 at which a predetermined second time T2 elapses, the fade control signal ? Output b. As a result, the motor 3a of the Faygoux circuit 3 is driven, and the volume 6b is gradually turned down accordingly, so that the level of the output signal 4a of the amplifier circuit 4 gradually decreases.

At time t4, the control circuit 9 stops outputting the fade control signal 9b and outputs the power supply control signal 9a. As a result, as in the case of FIG. 2, the power to the tune circuit 1 and the amplifier circuit 4 is turned off, and the output signal 4a of the amplifier circuit 4 is completely no longer output after time t4.

That is, in the case of FIG. 3, the power is turned off after the audio signal level is gradually lowered.

FIG. 4 is a circuit diagram showing a specific example of the level detection circuit 7 shown in FIG. 1.

In the figure, diode 7b performs half-wave rectification on input signal 2a. The capacitor 7d smoothes the half-wave rectified signal. The comparison circuit 7f compares the potential v1 of the smoothed signal.
and the potential VB of the battery 7g, and the potential v1 is the battery 7g.
When the potential of g is lower than VB, a level detection signal 7a is output. Note that the resistor 7e is a resistor for determining the time constant of discharging the electric charge charged in the capacitor 9-7d.

The operation of the level detection circuit 7 shown in FIG. 4 will be explained below using FIG. 5. In Figure 5, the same symbols as in Figure 4 are
4 shows a signal waveform at the corresponding symbol point in FIG. 4.

The input signal 2a is half-wave rectified by passing through the diode 7b as shown by the broken line in FIG. is supplied to the (-) input terminal of The rising time constant of the signal supplied to this (-) input terminal is determined by the on-resistance value of the diode 7b and the capacitance value of the capacitor 7d, and the falling time constant is determined by the resistance value of the resistor 7e. , capacitor 7d
It is determined by the capacitance value of

The comparison circuit 7f receives a signal 7c supplied to the (-) input terminal.
It compares the potential of the signal 7c with the potential VB of the battery 7g supplied to the (+) input terminal, and outputs the level detection signal 7a when the potential of the signal 7c is less than the potential vB.

In the above explanation, the tuner circuit 1 is provided to obtain the input signal 2a, but in the present invention, instead of the tuner circuit 1, for example, a CD player or a TV player is used.
It is also possible to provide other audio equipment such as

Further, the first time T1 and the second time T2 described above do not need to be fixed, and may be set freely by the user.

〔Effect of the invention〕

According to the present invention, the sleeve function of the timer makes it possible to turn off the power to an audio device either during a silent section or after fading out the volume of the sound emitted from the speakers, for example. The power won't turn off when playing music such as Flymax. Therefore, according to the present invention, there is an effect that the user does not feel uncomfortable.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIGS. 2 and 3 are waveform diagrams for explaining the operation of FIG. 1, and FIG. 4 is a specific example of the level detection circuit of FIG. 1. FIG. 5 is a waveform diagram for explaining the operation of FIG. 4. Explanation of symbols 2...Signal input terminal, 3...Fader circuit, 4...Amplification circuit, 7...Level detection circuit, 10... ...Timer circuit, 6, 8...
...Power switch, 9...Control circuit. No. 21. ￥】 Ma 1 ￥] 1 year old T ν Bell Oya Exit Road 7 Kure Bell # Output signal system 5 diagram

Claims (2)

[Claims] (1) A signal input terminal into which an audio demodulated signal (hereinafter simply referred to as an audio signal) is input, an amplifier circuit which amplifies the audio signal supplied through the signal input terminal and drives a speaker, and the amplifier circuit In an audio device having a power switch for controlling power on/off, the level of the audio signal supplied through the signal input terminal is compared with a predetermined reference voltage, and when the audio signal level is below the reference voltage, the level is determined. a level detection circuit that outputs a detection signal, a fader circuit that controls the level of an audio signal supplied to the amplifier circuit, a timer circuit that detects a set time set from the outside and outputs a time detection signal, and the fader circuit that outputs a time detection signal. a control circuit that controls the circuit and the power switch based on the time detection signal and the level detection signal; If the level detection signal is output from the level detection circuit before the first time elapses, a power control signal is output to turn off the power switch at the time when the level detection signal is output, while the first
If the level detection signal is not output before the elapse of time, the level of the audio signal supplied to the amplifier circuit is gradually reduced from the first time elapsed time to the scheduled second time elapsed time. A timer-based power supply control device for an audio device, characterized in that the fader circuit outputs a fade control signal to the fader circuit, and outputs a power supply control signal for turning off the power switch at the second elapsed time. (2) A timer-based power supply control device for an audio device according to claim 1, wherein the fader circuit comprises a motor and a volume driven by the motor.