JP2607664B2 - Equipment with noise elimination circuit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device having a noise elimination circuit, and any device having a power supply line and an information line, in particular, an AV device.
It is used in the field of related devices and information-related devices.

[Prior Art] FIG. 3 shows a schematic configuration of a conventional device including a noise removing circuit. In the figure, reference numeral 1 denotes a power supply line, which is connected to, for example, a commercial AC power supply. An information line 2 is connected to, for example, a telephone line. The power supply circuit 10 obtains a power supply voltage for driving the device from the power supply line 1. The signal processing circuit 20 sends and receives signals to and from the information line 2. Power line 1 and information line 2
Disturbance voltage blocking circuits 3 and 4 each composed of a ferrite core or the like are inserted to remove the disturbance voltage.

[Problems to be Solved by the Invention] However, in the above-described conventional example, only the noise generated in the power supply line 1 and the noise generated in the information line 2 are blocked by the disturbance voltage blocking circuits 3 and 4, respectively. However, the disturbance voltage induced between the power supply line 1 and the information line 2 could not be removed. Here, it is not possible to specify what kind of disturbance voltage is induced between the power supply line 1 and the information line 2, but for example, a high frequency inverter type lighting device, a computer display device, There are countless disturbing voltages in the space, such as power supply devices, air conditioners and other motors, natural phenomena such as lightning and discharge, and spark noise of automobile engines, which interfere between the power line 1 and the information line 2. It is presumed to be induced as a voltage. The power supply line 1 and the information line 2 connected to the device have an antenna function of picking up noise in the space and inducing an interference voltage, and conversely, radiating the interference voltage into the space. However, it was inevitable that such an interference voltage would be mixed into the wiring of the signal processing circuit 20. As described above, in the conventional example, since the interference voltage induced between the power supply line 1 and the information line 2 is not vulnerable to the adverse effect on the device, for example, the reception image of the AV-related device is not protected. There has been a problem that disturbances and malfunctions in information-related devices occur.

The present invention has been made in view of such a point,
An object of the present invention is to provide a device having a noise elimination circuit that can effectively eliminate an interference voltage induced between a power supply line and an information line.

[Means for Solving the Problems] In the present invention, in order to solve the above-mentioned problems, as shown in FIG. 1, a power supply line 1 and an information line 2 are provided and connected to the power supply line 1. In a device having a built-in first circuit (power supply circuit 10) and a second circuit (signal processing circuit 20) connected to the information line 2, high-frequency waves induced between the power line 1 and the information line 2 Voltage bypass circuit 5 composed of a capacitor or the like that constantly exhibits a low impedance with respect to the disturbance voltage
Are built in so as to be interposed between the power supply line 1 and the information line 2.

It is more preferable to dispose disturbance voltage blocking circuits 3 and 4 for blocking a disturbance voltage between the disturbance voltage bypass circuit 5 and the first and second circuits.

[Operation] In the present invention, as described above, the power supply line 1 and the information line 2
Since a disturbance voltage bypass circuit 5 composed of a capacitor or the like that constantly exhibits a low impedance with respect to a high-frequency disturbance voltage induced between the power supply line 1 and the information line 2 is incorporated therein, In addition, the disturbance voltage induced between the power supply line 1 and the information line 2 does not adversely affect circuits such as the power supply circuit 10 and the signal processing circuit 20 in the equipment. Further, the disturbance voltage bypass circuit 5 and the first and second
Circuit, which blocks the disturbance voltage,
By arranging 4, it is possible to more completely eliminate the adverse effect due to the disturbance voltage.

Embodiment FIG. 1 is a schematic configuration diagram of an embodiment in which the present invention is applied to an information-related device such as a facsimile or a business computer. An interfering voltage bypass circuit 5 is interposed between the power supply line 1 and the information line 2, and an interfering voltage blocking circuit 3 is inserted between the power supply circuit 10 and the power supply line terminal 11, so that the signal processing circuit 20 The disturbance voltage blocking circuit 4 is inserted between the terminal 21 and the wire terminal 21. The disturbing voltage bypass circuit 5 is configured by a capacitor or the like that exhibits a lower impedance than an internal circuit with respect to a high-frequency disturbing voltage induced between the power supply line 1 and the information line 2. Therefore, the current caused by the disturbing voltage induced between the power supply line 1 and the information line 2 flows only through the disturbing voltage bypass circuit 5, and is disturbed in the space by the antenna function of the power supply line 1 and the information line 2. The voltage is not copied, and the inconvenience of interfering voltage in the space into the wiring of the signal processing circuit 20 can be prevented. Further, the disturbance voltage blocking circuits 3 and 4 are constituted by filter circuits exhibiting a high impedance with respect to the disturbance voltage, and are made small and lightweight using a magnetic material having a high magnetic permeability such as a ferrite core. According to the results of our trial measurement, the noise reduction effect was 15 dB at the maximum and about 10 dB at the average. This can prevent a malfunction such as a transmission error due to an interference voltage. Further, even if sudden noise such as lightning is mixed, an effect that the device is not adversely affected can be expected.

Next, FIG. 2 shows a schematic configuration of an embodiment in which the present invention is applied to a television receiver. This embodiment has the same configuration as the embodiment of FIG. 1 except that a television receiving circuit 22 is connected instead of the signal processing circuit 20. As described above, if the present invention is applied to a television receiver, it is possible to prevent an interference voltage induced between the power supply line 1 and the information line 2 from being mixed into the receiving circuit 22, and to prevent inconvenience such as disturbance of a received image. It can be eliminated.

In the description of the embodiment, an example in which the present invention is applied to an information processing-related device such as a facsimile or a business computer and an AV-related device such as a television receiver has been described. It goes without saying that the present invention is effective for all devices having two lines.

[Effects of the Invention] According to the present invention, as described above, a disturbance voltage bypass circuit including a capacitor or the like that constantly exhibits a low impedance with respect to a high-frequency disturbance voltage induced between a power supply line and an information line is provided. Since the power supply line and the information line are interposed between the power supply line and the information line, the interference voltage induced between the power supply line and the information line does not adversely affect the circuit in the device.

Further, by disposing a disturbance voltage blocking circuit for blocking a disturbance voltage between the disturbance voltage bypass circuit and at least the first or second circuit, the effect that the adverse effect due to the disturbance voltage can be more completely eliminated. is there.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a first embodiment of the present invention, FIG. 2 is a schematic configuration diagram of a second embodiment of the present invention, and FIG. 3 is a schematic configuration diagram of a conventional example. is there. 1 is a power line, 2 is an information line, 3 and 4 are disturbance voltage blocking circuits, 5
Is a disturbance voltage bypass circuit, 10 is a power supply circuit, 11 is a power supply line terminal, 20 is a signal processing circuit, 21 is an information line terminal, and 22 is a receiving circuit.

Claims (2)

(57) [Claims] 1. An apparatus having a power supply line and an information line, wherein a first circuit connected to the power supply line and a second circuit connected to the information line are built in, between the power supply line and the information line. A disturbance voltage bypass circuit composed of a capacitor or the like that constantly exhibits a low impedance with respect to a high-frequency disturbance voltage induced in
A device having a noise elimination circuit, which is built in so as to be interposed between a power supply line and an information line. 2. The noise elimination circuit according to claim 1, further comprising an interference voltage blocking circuit for blocking an interference voltage between the interference voltage bypass circuit and at least the first or second circuit. Equipment.