JPH0755732Y2 - Function display circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a function display circuit of a component stereo equipped with a source device such as a tuner, a tape deck, or a compact disc player.

(B) Conventional technology A component stereo equipped with a source device such as a tuner, a tape deck, a compact disc player (hereinafter referred to as a CD player) has been widely used. In such an audio device, it is generally known that the source device is selected by operating the function switch and, at the same time, the source device currently selected is displayed to the user by an LED display or the like.

FIG. 2 shows a circuit configuration of the conventional audio equipment as described above.

In the figure, (1) is a tuner section, (2) is a tape deck section, and (3) is a CD player section. (4) is a function circuit, and the tuner section (1) as a source device
-Each audio signal from the tape deck section (2) -CD player section (3) is input to each signal input port (IN1) (IN2) (IN
3), and selectively outputs these audio signals from the output port (OUT). The signal output from the output port (OUT) is the direct switch (D
It is led to the equalizer circuit (5) for frequency correction via S). The movable contact A of the direct switch (DS) is normally set to the contact B side, and is configured to interlock with the switching operation of the function direct switch described later.
(6) is an amplifier circuit that amplifies the audio signal that has passed through the equalizer circuit (5), and (7) is a speaker that emits the amplified signal. On the other hand, (8) is a selection / display circuit for instructing the function circuit (4) to select a source device and displaying the selected source device. Each function switch (FS1) (FS2) (FS3) connected to each selection control port (C1) (C2) (C3) of the function circuit (4) and the display LED (L1) connected in parallel with it (L2) and (L3), and a push-lock function direct switch (FDS) provided in parallel with the function switch (FS3). The selection control port (C1) (C2) (C
3) is normally in the HI state, and when any of the function switches (FS1) (FS2) (FS3) is operated, the selected control port (C1) (C2) (C3) is selected accordingly. Port is set to the LO state and this state is maintained until another function switch is operated. That is, when another function switch is operated, the port to which the operated function switch is connected becomes LO, and the port that has been LO until then returns to HI. Therefore, in response to the operation of the function switches (FS1) (FS2) (FS3), the tuner unit (1), the tape deck unit (2), and the CD player unit (3) which are the source devices can be selected and the selected source can be selected. The display LED corresponding to the device lights up.
Then, the audio signal of the selected source device is emitted from the speaker (7). When the function direct switch (FDS) is operated instead of the function switches (FS1) (FS2) (FS3),
In conjunction with the operation, the movable contact A of the direct switch (DS) is switched to the contact C side, and the function direct switch (FDS) and the direct switch (DS) are held in this state. Therefore, the CD player unit (3) is selected as the source device, and the audio signal output from the function circuit (4) is guided to the amplifier circuit (6) without passing through the equalizer circuit (5). The signal purity can be maintained by preventing the deterioration of the SN ratio and the change / deterioration of the sound quality caused by passing through (5).

(C) Problems to be solved by the invention However, in the above circuit configuration, when the CD player (3) is selected by operating the function direct switch (FDS), other function switches (FS1) (FS2) If either of the above is operated, the function circuit (4) does not switch the selection of the source device, but the operated function switch (FS1) or (F
Display LED (LED1) or display LED (LE
D2) will light up. Therefore, a display appears as if two types of source devices are selected, which causes a problem of confusing the user.

(D) Means for Solving the Problems The present invention has been made in view of the above problems, and is a display circuit of a device having a source device such as a tuner, a cassette deck, a CD player, etc. Function circuit that selectively outputs the audio signal of
An equalizer circuit for guiding the audio signal output from the function circuit and correcting the frequency of the audio signal, an amplifier circuit for amplifying the signal passed through the equalizer circuit, and an equalizer circuit for the audio signal from the function circuit Direct switch that can be switched so as to lead to the amplifier circuit without passing through, a function switch for instructing the function circuit to select each source device, and at least one of the function switches in parallel. A push-lock function direct switch that is provided and interlocks with the direct switch, a display LED that lights up in response to the operation of the function switch or the function direct switch, and the function director. In connection with the operation of the switch, for display of the source device other than the source device selected by the function directly switch among the display LED
It is an object of the present invention to solve the above-mentioned problems by providing a switching means for cutting off the power supply to the LED.

(E) Operation With the above configuration, the switching means cuts off the power supply to the display LED of the source device other than the source device selected by the function direct switch among the display LEDs according to the operation of the function direct switch. Be drunk

(F) Embodiment One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a circuit configuration of an audio device to which the function circuit according to the present invention is applied. The same parts as those of the conventional audio device are designated by the same reference numerals and the description thereof will be omitted.

In the present invention, when the function direct switch (FDS) is operated, a cut-off transistor (TR) is a switching means for cutting off the power supply to the display LED for displaying the selection of another source device.
1) and a control transistor (T
R2) is provided.

To explain the operation in detail, the control transistor (TR2) turns off when the function direct switch (FDS) is operated.
To ON. This turns the cut-off transistor (TR1) from ON to OFF, so no matter which of the function switches (FS1) and (FS2) is operated, the display LED
(LED1) or display LED (LED2) does not light up.

(G) Effect of the Invention According to the present invention as described above in detail, according to the present invention, a display circuit of a device having a source device such as a tuner, a cassette deck, a CD player, etc., and an audio signal from each of the source devices is selected. Function circuit that outputs the audio signal, an equalizer circuit that guides the audio signal output from the function circuit and corrects the frequency of the audio signal, an amplifier circuit that amplifies the signal that has passed through the equalizer circuit, and the function A direct switch that can be switched so as to guide the audio signal from the circuit to the amplifier circuit without passing through the equalizer circuit, a function switch for instructing the function circuit to select each of the source devices, and the function The switch is provided in parallel with at least one of the switches, and And Electricity push-lock function direct switch to link the switch, and the display LED that lights in response to the operation of the function switch or function direct switch, in connection with the operation of the function direct switch, the display LE
Since it has switching means that cuts off the power supply to the display LED of the source device other than the source device selected by the function direct switch of D, while the CD player is selected by the operation of the function direct switch, When the function switch that selects the source of is operated, the corresponding display LED
Is lit, and the problem that the user is confused by the display as if two types of source devices are selected can be eliminated, which is extremely useful in practice.

[Brief description of drawings]

FIG. 1 is a diagram showing a circuit configuration of an audio device according to the present invention,
FIG. 2 is a diagram showing a circuit configuration of a conventional audio device. (1) ... Tuner part, (2) ... Tape deck part, (3)
... CD player, (4) ... Function circuit, (5)
… Equalizer circuit, (6)… Amplifier circuit, (FS1) (FS2)
(FS3) ... Function switch, (L1) (L2) (L
3)… LED for display, (DS)… Direct switch, (FD
S)… Function direct switch, (TR1)… Cutoff transistor (switching means).

Claims (1)

[Scope of utility model registration request] 1. A display circuit of a device having a source device such as a tuner, a cassette deck, and a CD player, wherein the function circuit selectively outputs an audio signal from each of the source devices, and the function circuit outputs the function signal. An equalizer circuit that guides an audio signal and corrects the frequency of the audio signal, an amplifier circuit that amplifies a signal that has passed through the equalizer circuit, and an audio signal that has been amplified from the function circuit without passing through the equalizer circuit. A direct switch that can be switched so as to lead to a circuit; a function switch for instructing the function circuit to select each source device; and a direct switch that is provided in parallel with at least one of the function switches. Push to interlock Block-type function direct switch, a display LED that lights up in response to the operation of the function switch or the function direct switch, and a function direct switch of the display LEDs that is selected in association with the operation of the function direct switch. And a switching means for cutting off the power supply to the display LED of the source device other than the source device.