KR20000074852A - Circuit for removing a noise of a power supply apparatus and a line pattern of the circuit - Google Patents

Abstract

PURPOSE: A noise reducing circuit of a power system and a circuit pattern thereof are provided to effectively reduce the noise by forming a filter at a front portion of a fuse. CONSTITUTION: A noise reducing circuit of a power system comprises the first wire(110) which is formed at a live terminal of a power input terminal. The second wire(120) is provided in such a manner that a fuse(10) can be interposed between the second wire(120) and the first wire(100). The third wire(130) is formed at a natural terminal in parallel to the first wire(110). The third noise removing section(100) includes a discharging device which is connected between the fist wire(110) and the third wire(130) and a noise removing device. The discharging device is a resistance and the noise removing device is a capacitor.

Description

Noise canceling circuit of power supply and its circuit pattern {CIRCUIT FOR REMOVING A NOISE OF A POWER SUPPLY APPARATUS AND A LINE PATTERN OF THE CIRCUIT}

The present invention relates to a power supply.

More specifically, the present invention relates to a noise removing circuit and a circuit pattern of a power supply device for efficiently removing low frequency noise introduced into an internal circuit from an AC power input side, or high frequency noise that is a switching frequency conducted from an internal circuit to an AC power input side. will be.

With the recent development of technology, various devices are spreading, and most of the devices described above operate by being supplied with power. Each person has at least one or more of the above-mentioned devices, and in order to supply power to the device, a multi-tap is connected to an outlet supplied with AC 110 / 220V, which is a commercial power source. Connect the power plug.

In this case, when a predetermined device is operated because a power plug of a plurality of devices is in close proximity to the above-described multi-tap, electromagnetic waves generated by the device are introduced into another device, and the introduced electromagnetic waves act as noise in the device. Noise may occur or malfunctions may occur.

1 is a diagram illustrating a noise removing circuit of a power supply apparatus according to the prior art.

As shown, the first noise removing unit 20 and the first noise removing unit 20 are formed at the rear end of the fuse 10 to remove noise flowing from the power input terminal from the live stage to the natural stage. It consists of a second noise removing unit 30 for removing residual noise that is not removed.

The first and second noise removing units 20 and 30 described above include capacitors C1 and C4 for removing low-frequency noise and coils for removing high-frequency noise, which is a switching frequency conducted from a later stage to the power input side. It consists of (L1) (L2) and capacitor | condenser C2 (C3) (C5) (C6).

FIG. 2 is a view of the circuit pattern of FIG. 1, in order to protect the circuit blocks at the rear end from transients of the input power supply, the fuse is far from the circuit end due to the safety standard set by the Safety Association and the mechanical arrangement of the input power source. Will be located away.

In addition, each of the wires 40, 50 and 60 is lengthened to satisfy the stability standard, and should be implemented in a limited space, so that the wirings 40, 50, and 60 are formed with curvature as shown in the drawings.

In the noise removing circuit of the power supply device having the above-described configuration, the low-frequency noise flowing into the circuit side provided in the set of devices from the power supply input terminal through the fuse 10 is first used as the capacitor C1 of the first noise removing unit 20. Is removed. At this time, the noise remaining without being removed is removed by the condenser C4 of the second noise removing unit 30.

On the other hand, high frequency noise, which is a switching frequency generated on the circuit side provided in the set of devices, is a high frequency, which is removed by the coil L2 and the condenser C5 and C6 of the second noise removing unit 30 to the power input side. In this case, the switching noise that has not been removed is removed by the coil L1 and the condenser C2 and C3 of the first noise removing unit 20.

However, in the case of implementing the noise removing circuit of the power supply as in the prior art, the position of the fuse installed to protect the circuits of the latter stage from the transient of the input power is slightly different depending on the implementation of all the devices including the video display device. However, most of them are implemented in a pattern having a thickness of 2.5 mm to 4 mm at a position about 3 to 4 cm away from the input.

At this time, impedance, inductance, conductance, etc. exist according to the length of the pattern and the thickness of the copper foil of the pattern, and these values are different depending on the implementation method. Therefore, the generated noise is conducted and induced according to the switching frequency of the power supply and the circuit. Will be

Therefore, in the prior art, the filter was formed in two stages to remove the noise, but when the filter is formed in two stages as described above, there was a problem that many parts are required and complicated. The filter may be replaced with a filter formed in one stage, but in this case, there is a problem that the size of one filter increases.

Accordingly, an object of the present invention is to provide a power source for efficiently eliminating high frequency noise, which is a switching frequency at which low frequency noise is conducted to an internal circuit at an AC power input side or conducted to an AC power input side at an internal circuit so as to solve the above problems. To provide a noise reduction circuit and a circuit pattern of the device.

1 is a view showing a noise removing circuit of a power supply apparatus according to the prior art;

2 is a view showing a circuit pattern of FIG.

3 is a diagram illustrating a noise removing circuit of a power supply apparatus according to the present invention;

4 is a diagram illustrating a circuit pattern of FIG. 3;

5 is a graph showing the noise generated in the prior art and the present invention.

* Description of Signs of Main Parts of Drawings *

100: third noise removing unit 110: first wiring

120: second wiring 130: third wiring

C7: Capacitor R1: Resistance

The present invention for achieving the above object is formed in the front end of the fuse, the third noise removing unit for removing the low frequency noise flowing from the power input terminal, the high frequency noise of the switching frequency conducted to the power input terminal, and the third And a second noise removing unit for secondarily removing noise not removed by the noise removing unit, and a fuse for outputting power flowing from the third noise removing unit to the second noise removing unit.

The present invention for achieving the above object is formed on the live end of the power input terminal, the first wiring having a linearity, the second wiring having a fuse between the first wiring, the linearity of the disconnection, and the natural end And a third noise removing portion having a third wiring formed in parallel with the first wiring, and a discharge element and a noise removing element connected in parallel between the first wiring and the third wiring.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating a noise removing circuit of a power supply apparatus according to the present invention.

As shown, the third noise removing unit 100 is formed at the front end of the fuse 10 to remove the low frequency noise flowing from the power input terminal, and to remove the high frequency noise which is a switching frequency conducted to the power input terminal, The second noise removing unit 30 which secondly removes the noise not removed by the third noise removing unit 100, and the power flowing from the third noise removing unit 100 to the second noise removing unit 30. It consists of the fuse 10 which outputs.

The third noise removing unit 100 described above is a capacitor C4.

In addition, the third noise removing unit 100 further includes a discharge device for discharging the residual voltage of the capacitor C7 when the fuse 10 is opened. The discharge element described above is a resistor R1.

4 is a diagram illustrating a circuit pattern of FIG. 3.

As shown, a second wiring formed at the live end of the power input terminal having a linearity and a fuse 10 between the first wiring 110 and the first wiring 110 and having a linearity of disconnection 120, a third wire 130 formed at a natural end in parallel with the first wire 110, and a discharge element and noise connected in parallel between the first wire 110 and the third wire 130. And a third noise removing unit 100 having a removing element.

The discharge element described above is a resistor R1, and the noise canceling element is a capacitor C7.

The operation of the noise canceling circuit of the power supply apparatus constructed as described above will be described in more detail with reference to the accompanying drawings.

First, when a user connects power to a device and operates the device, low frequency noise is introduced into a predetermined device through a transformer from a power plant, but the low frequency noise is input to a circuit block provided in the predetermined device through the fuse 10. Previously passed through the capacitor C7 of the third noise removing unit 100 formed close to the power input side from the live end to the natural end, and the noise is not removed through the fuse 10, the second noise removing unit 30 ) Is entered.

Then, since the noise that is not removed by the third noise removing unit 100 is secondarily removed by the capacitor C4 of the second noise removing unit 30, low frequency noise flowing from the power input side is completely cut off and is applied to the rear stage. It does not affect the circuits provided.

The switching frequency, which is a high frequency generated at the circuit side of the device, is cut off by the coil L2 and the capacitor C5 and C6 of the second noise removing unit 30 as in the prior art, and has not been removed. Is passed to the natural end by the capacitor C7 of the third noise removing unit 100 and is completely removed.

If the fuse 10 is open, the voltage remaining in the capacitor C7 of the third noise removing unit 100 is discharged by the resistor R1 and is normally operated again. Should work properly.

As described above, noise components due to patterns that may be generated initially may be removed before passing through the fuse 10.

5 is a graph of a conventional case of forming the first noise canceling unit 20 at the rear end of the fuse 10 and a case of the present invention of forming the third noise removing unit 100 at the front of the fuse 10. When the first noise removing unit 20 is formed at the rear end of the fuse 10, it can be seen that a lot of noise components are generated between 10 megahertz and 30 megahertz. This noise component is mostly caused by the influence of the circuit pattern.

In contrast, when the third noise removing unit 100 is formed in front of the fuse 10, the noise component may be removed between 10 megahertz and 30 megahertz.

Therefore, as described above, the present invention can be easily implemented in a limited space by changing a pattern of the wiring of the live stage and the natural stage of the fuse front end and removing the noise between the wirings, and the component arrangement and Implementing the circuit pattern differently removes the noise completely.

Claims (4)

A third noise removing unit formed at a front end of the fuse to remove low frequency noise introduced from a power input terminal and to remove high frequency noise which is a switching frequency conducted to the power input terminal; A second noise remover for secondarily removing noise not removed by the third noise remover; And a fuse for outputting power flowing from the third noise removing unit to the second noise removing unit. 2. The apparatus of claim 1, wherein the first noise canceling circuit unit; Noise canceling circuit of a power supply, characterized in that the noise canceling element that passes the noise generated in the live stage to the natural stage. The method of claim 1 or 2, wherein the first noise removing circuit portion, And a discharge device for discharging the residual voltage of the noise removal device when the fuse is opened. A first wiring formed at a live end of the power input terminal and having linearity; A second wiring having a fuse between the first wirings and having a straight line linearity; A third wiring formed at a natural end in parallel with the first wiring; And And a third noise removing unit having a discharge element and a noise removing element connected in parallel between the first and third lines.