JPH11162574A - Plug discriminating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To discriminate between an AV plug and a headphone plug. SOLUTION: A four-terminal jack 60 has terminals 60a to 60d connected to respective terminals of an AV plug and a headphone plug. A movable terminal 60e contacts with a terminal 60f at plug uninserted time, and separates by insertion of the plugs. The terminals 60a to 60d are separated from output circuits 62 to 70 by opening of a switch 74. A signal generating circuit 78 impresses it on the terminal 60b by generating a plug discriminating probe signal. In the case of the headphone plug, electric potentials of the terminals 60b and 60c become equal to each other, and in the case of the AV plug, they become inconsistent. A comparing circuit 84 impresses a comparing result on a control circuit 86 by comparing the electric potentials of both terminals 60b and 60c. The control circuit 86 connects the terminal 60a to 60d to a switch 72 by stopping an impression of the probe signal, and connects the terminals 60a to 60d to the proper output circuits 62 to 70 by switching switches 72a to 72c according to the comparing result of the comparing circuit 84 by closing a switch 76.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plug identification device for identifying plugs having different numbers of contacts and connecting them to an appropriate circuit.

[0002]

2. Description of the Related Art In the process of reducing the size of video and audio equipment, various components are reviewed. However, signal output terminals must be of the standardized RCA standard. This is one factor that hinders miniaturization. Therefore, a signal output terminal having a modified shape has been proposed on the premise of a special audio / video cable. FIG. 4 shows the configuration of the AV plug. Reference numerals 10, 12, and 14 denote RCA standard plugs, which are connected to the AV plug 18 via the composite cable 16. On the AV plug 18, an audio R channel terminal 20, a ground terminal 22, a video terminal 24, and an audio L channel terminal 26 are axially separated by insulators 28, 30, and 32 in this order. .

However, a camera-integrated recording / reproducing device includes
It often has a headphone jack with a similar shape. FIG. 5 shows the configuration of the headphone plug attached to the headphone jack. Reference numeral 40 denotes a headphone plug, and a ground terminal 42, an R channel terminal 44, and an L channel terminal 46 are connected to insulators 48, 50 in this order.
Are arranged in between. 52 is an L-channel speaker diaphragm, 54 is an R-channel speaker diaphragm,
Reference numeral 56 denotes an L-channel voice coil, and reference numeral 58 denotes an R-channel voice coil. The voice coil 56 is connected between the L channel terminal 46 and the ground terminal 42, and the voice coil 58 is connected between the R channel terminal 44 and the ground terminal 42.

[0004] By providing a jack that can receive both the AV plug shown in FIG. 4 and the headphone plug shown in FIG. 5, the space for the signal output terminal can be reduced.

[0005]

However, FIG. 4 and FIG.
As can be seen from the above, since the position of each contact point and the signal of the head plug differ between the AV plug and the head plug, it is necessary to detect which is inserted.

An object of the present invention is to provide a plug identification device capable of identifying plugs having different numbers of contacts and positions.

[0007]

SUMMARY OF THE INVENTION A plug identification device according to the present invention identifies a plug connected to a jack having a plurality of terminals, which is freely connectable to a plurality of types of plugs having different numbers of terminals, and forms an appropriate circuit. A plug identification device to be connected, comprising: insertion detection means for detecting insertion of a plug into the jack; first switch means for separating the plurality of terminals from others; and a probe for identifying a plug to be connected to the jack. A probe signal generating means for generating a signal and applying the signal to a first terminal of the plurality of terminals, and comparing a potential between the first terminal and another second terminal of the plurality of terminals. Comparing means, selective connecting means for selectively connecting a plurality of terminals of the jack via the first switch means to a signal circuit corresponding to a plug to be connected, and plug insertion detection of the insertion detecting means The plurality of terminals are separated from the other by the first switch means in accordance with the signal, and the type of plug inserted is determined by the output of the comparison means in the applied state of the probe signal generated by the probe signal generation means. And a control means for controlling the selection connection means in accordance with the result of the determination.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic block diagram showing an embodiment of the present invention.

Reference numeral 60 denotes a four-terminal jack corresponding to both the AV plug shown in FIG. 4 and the headphone plug shown in FIG. 5. The ground terminal 60a is connected to the ground terminals 22 and 42 of the AV plug and the headphone plug. And audio L channel terminal 2 for headphone plug
Audio L-channel terminal 60b connected to 6, 46, AV
A video / audio terminal 60 connected to the video terminal 24 of the plug and the audio R channel terminal 44 of the headphone plug.
c, an audio / ground terminal 60d connected to the audio R channel terminal 20 of the AV plug and the ground terminal 42 of the headphone plug, a movable terminal 60e that can be displaced in the radial direction of the axis of the plug by inserting an appropriate plug, and When it is not inserted, it comes into contact with the movable terminal 60e,
It has a plug detection terminal 60f that separates from the movable terminal 60e when a plug is inserted.

Reference numeral 62 denotes an audio R to be output together with the video signal.
An audio R channel output circuit for outputting a channel signal,
64 is a video output circuit for outputting a video signal, 66 is an audio L channel output circuit for outputting an audio L channel signal to be output together with the video signal, and 68 is an audio L channel signal to be supplied to an L channel speaker. The headphone L channel output circuit 70 is a headphone R channel output circuit that outputs a sound R channel signal to be supplied to the R channel speaker.

Reference numeral 72 denotes an output circuit 62, 64, 6 according to whether the inserted plug is an AV plug or a headphone plug.
6 or a switch for selecting the output circuits 68 and 70,
It consists of three switches 72a, 72b, 72c. The switch 72a selects the audio R channel output circuit 62 (selection contact a) for the AV plug, and selects the contact b that is not connected to the headphone plug. Switch 72b
Is an audio L channel output circuit 66 for the AV plug.
(Selection contact a) is selected, and the audio L channel output circuit 68 (selection contact b) is selected for the headphone plug. The switch 72c selects the video output circuit 64 (selection contact a) for the AV plug, and selects the audio R channel output circuit 70 (selection contact b) for the headphone plug.

Reference numeral 74 denotes a switch for disconnecting the terminals 60b, 60c, and 60d of the jack 60 from the switch 72 to detect whether the plug attached to the jack 60 is an AV plug or a headphone plug. 76 denotes a ground terminal 60a. A switch for connecting to or disconnecting from the ground, 78 is a probe signal generation circuit for generating a probe signal for detecting whether the inserted plug is an AV plug or a headphone plug, and 80 is a sound L channel for outputting a probe signal output from the probe signal generation circuit 78 A switch for controlling whether or not the voltage is applied to the terminal 60b is provided.
An insertion detection circuit 84 detects the insertion of a plug according to the presence or absence of the connection of the plugs f and 60e. A comparison circuit 84 compares the potential between the terminals 60b and 60c. A switch 74 determines the type of the inserted plug. , 76 and a switch 80 via an inverter 88, and a switch 72 based on the result of the determination.

The operation of this embodiment will be described. The switches 74 and 76 are initially open, and the switch 80 is closed.

First, it is detected whether or not a plug is inserted into the jack 60. Specifically, the insertion detection circuit 82
Checks whether the terminals 60e and 60f are short-circuited or open. When short-circuited, the plug is not inserted, and when open, the plug is inserted, and the control circuit 86 is notified of this fact.

When the insertion detection circuit 82 detects that a plug has been inserted into the jack 60 and notifies the control circuit 86, the control circuit 86 causes the probe signal generation circuit 78 to generate a probe signal. This probe signal is sent to switch 8
0 is applied to the terminal 60b.

When the inserted plug is an AV plug, the terminals 60a to 60f of the jack 60 are connected to the audio R terminal 20 as shown in FIG.
The terminals 60a and 60e contact the ground terminal 22, the terminal 60c contacts the video terminal 24, and the terminal 60b contacts the audio L terminal 26.

When the inserted plug is a headphone plug, the terminals 60a to 60f of the jack 60 have the terminals 60a, 60d and 60e in contact with the ground terminal 42 and the terminal 60c has the audio R terminal as shown in FIG. 44, and the terminal 60b contacts the audio L terminal 46.

If the inserted plug is an AV plug, even if a probe signal is applied to the terminal 60b, the video terminal 2
4 and the audio L channel terminal 26 are completely separated electrically, so that the potential of the terminal 60c is completely independent of the probe signal. Therefore, the comparison circuit 84 outputs a mismatch signal to the control circuit 86. This mismatch signal is
This means that the inserted plug is an AV plug.
The control circuit 86 stops the probe signal output of the probe signal generation circuit 78 (that is, opens the switch 80) in response to the mismatch signal from the comparison circuit 84, and connects the individual switches 72a, 72b, 72c of the switch 72 to the a contacts. , The switches 74 and 76 are closed. Thus, the terminal 60a is connected to the ground, the terminal 60b is connected to the audio L channel output circuit 66, the terminal 60c is connected to the video output circuit 64, and the terminal 60d is connected to the audio R channel output circuit 62. That is, the correct circuits 62, 64, 66 are connected to the AV plug.

When the inserted plug is a headphone plug, since the switch 76 is open, the terminal 60b
Is applied to the voice coil 58 of the R channel through the voice coil 56 of the L channel. If the input impedance of the comparison circuit 84 is set sufficiently high, the same signal applied to the terminal 60b will appear at the terminal 60c as it is. Even if the probe signal is in the audible band, since no signal current flows through the voice coils 56 and 58, unnecessary signal sounds are not output, but unnecessary sounds (including vibration sounds) are not generated. Thus, it is preferable that the frequency is outside the audible band. Since the two inputs of the comparison circuit 84 become the same signal, the comparison circuit 84 outputs a coincidence signal to the control circuit 86. This coincidence signal means that the inserted plug is a headphone plug. The control circuit 86 stops the probe signal output of the probe signal generation circuit 78 (that is, opens the switch 80) in response to the coincidence signal from the comparison circuit 84, and connects the individual switches 72a, 72b, 72c of the switch 72 to the b contacts. , The switches 74 and 76 are closed. Thus, the terminal 60a is connected to the ground, the terminal 60b is connected to the audio L channel output circuit 68, and the terminal 60c is connected to the audio R channel output circuit 70. That is, the correct circuits 68 and 70 are connected to the headphone plug.

[0021]

As can be easily understood from the above description, according to the present invention, which of a plurality of types of plugs having a different number of terminals, such as a headphone plug and an AV plug, is connected is determined by the impedance and the like. Can be reliably identified. By switching the connection of the output circuit according to the identification result, a correct circuit can be connected to each terminal of the plug.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

FIG. 2 is a side view showing a state in which an AV plug is attached to a jack 60.

FIG. 3 is a side view showing a state in which a headphone plug is attached to a jack 60.

FIG. 4 is a side view of the AV plug.

FIG. 5 is a side view of a headphone plug.

[Explanation of symbols]

 10, 12, 14: plug 16: composite cable 18: AV plug 20: audio R channel terminal 22: ground terminal 24: video terminal 26: audio L channel terminal 28, 30, 32: insulator 40: headphone plug 42: ground Terminal 44: R channel terminal 46: L channel terminal 48, 50: insulator 52: L channel speaker diaphragm 54: R channel speaker diaphragm 56: L channel voice coil 58: R channel voice coil 60: 4 Terminal jack 60a: ground terminal 60b: audio L channel terminal 60c: video / audio terminal 60d: audio / ground terminal 60e: movable terminal 60f: plug detection terminal 62: audio R channel output circuit 64: video output circuit 66: audio L channel Output circuit 68: head Phone L channel output circuit 70: Headphone R channel output circuit 72, 72a, 72b, 72c: Switch 74: Switch 76: Switch 78: Probe signal generation circuit 80: Switch 82: Insertion detection circuit 84: Comparison circuit 86: Control circuit 88 : Inverter

Claims (4)

[Claims] 1. A plug identification device for identifying a plug connected to a jack having a plurality of terminals and connectable to an appropriate circuit, the plug identification device being connectable to a plurality of types of plugs having different numbers of terminals. Insertion detection means for detecting insertion of a plug; first switch means for separating the plurality of terminals from others; generating a probe signal for identifying a plug connected to the jack; A probe signal generating means applied to one terminal, a comparing means for comparing a potential between the first terminal and another of the plurality of terminals, and a first switch means A selective connection means for selectively connecting a plurality of terminals of the jack to a signal circuit corresponding to a plug to be connected; and a first switch means in response to a plug insertion detection signal of the insertion detection means. The plurality of terminals are separated from the others, the type of the inserted plug is determined by the output of the comparing means in a state where the probe signal generated by the probe signal generating means is applied, and the selection is performed according to the determination result. A plug identification device, comprising: control means for controlling connection means. 2. The plug identification device according to claim 1, wherein the plurality of plugs are an AV plug and a headphone plug. 3. The plug identification device according to claim 1, wherein the probe signal is a signal outside the audible band. 4. A ground terminal connected to a ground terminal of the AV plug and the headphone plug,
The audio L channel terminal connected to the audio L channel terminal of the AV plug and the headphone plug, the video / audio terminal connected to the video terminal of the AV plug and the audio R channel terminal of the headphone plug, the audio R channel terminal of the AV plug and the headphone plug The plug identification device according to claim 2, further comprising an audio / ground terminal connected to the ground terminal, wherein the first terminal is the audio L channel terminal, and the second terminal is the video / audio terminal.