JP2019161051A - Printed circuit - Google Patents

Abstract

To provide a printed circuit which can facilitate noise countermeasures using a ferrite core and a current waveform inspection using a probe.SOLUTION: A printed circuit 20 has wiring 12 formed on a printed board 11. The wiring 12 is divided at a specific point on the printed board 11, and a through-hole 13 is formed to be sandwiched from both sides by two pieces of the wiring 12 thus divided. The two divided pieces of the wiring 12 are brought into conduction by being connected to each other via a wire 14 provided over the through-hole 13. When performing a current waveform inspection using a probe, it is possible to facilitate the inspection by hooking a tip of the probe over the wire 14 at the specific point. It is also possible to take noise countermeasures by arranging an annular ferrite core 21 inside the through-hole 13 and then inserting the wire 14 into a ring of the ferrite core 21.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a printed circuit having wiring formed on a printed circuit board.

  An electronic circuit used in an electronic device is generally a printed circuit. A printed circuit is configured by forming a wiring pattern on a printed board by photolithography or printing and mounting electronic components thereon.

  A ferrite core is known as one of noise countermeasures in electronic circuits. The ferrite core for noise countermeasure is used in such a manner that a ferrite-like magnetic body is formed into a ring shape and wiring is passed through the ring.

  However, in a printed circuit, it is impossible to pass the wiring together with the substrate in the ring of the ferrite core with respect to the wiring pattern formed on the printed circuit board, and the ferrite core cannot be applied as it is. In order to use a ferrite core in a printed circuit, as shown in FIG. 5, a part of the wiring 100 where the ferrite core is used is cut, a lead wire 110 is attached to the cut location, and the attached lead wire 110 is ferrite. It is necessary to pass through the core 120.

  In addition, the wiring pattern formed on the printed circuit board has a problem that it is difficult to inspect the current waveform using a probe. Therefore, when inspecting the current waveform at an arbitrary location in the printed circuit, as in FIG. 5, the lead wire 110 is attached to the wiring 100 at the inspection location, and the tip of the probe is hooked on the lead wire 110 for inspection. Things have been done.

  If a lead wire is attached to the printed circuit later for noise countermeasures using a ferrite core or a current waveform inspection using a probe, a troublesome process is required. In addition, an inductance component is generated by the added lead wire, causing a problem that the performance of the electronic circuit is degraded.

  Patent Document 1 discloses a structure in which a noise countermeasure by a ferrite core is easily taken in a molded wiring board in which wiring is resin-molded. In the structure of Patent Document 1, two through holes are provided in a substrate so as to sandwich a molded wiring, and a ferrite core divided into two is inserted into and fixed to the through holes from the front and back of the substrate. The structure of Patent Document 1 is applied to an electronic circuit using a molded wiring board, but it is considered that the same structure can be applied to a printed circuit.

Japanese Patent Application Laid-Open No. 11-193952

  In the structure of Patent Document 1, the ferrite core is divided into two parts, and the divided ferrite cores are inserted into the through holes from the front and back of the substrate to sandwich the wiring. However, the divided ferrite core causes magnetic flux leakage at the divided portion, and the noise reduction performance is lower than that of the unintegrated integral ferrite core. Therefore, in order to obtain a desired noise reduction, a large ferrite core is required as compared with the case of using an integral ferrite core.

Patent Document 1 also discloses a structure using an integral ferrite core. In this structure, two notches are provided on the side surface of the substrate, and the wiring is routed in a U-shape at the protruding portion sandwiched between the notched portions, and the annular ferrite core is connected to the protruding portion on the side surface of the substrate. It is inserted from. However, this structure also has the following problems.
-Since the wiring is routed in a U-shape, an inductance component is generated at this location, and the performance of the electronic circuit is deteriorated (malfunction due to noise or the like is likely to occur).
• Wiring inserted into the ferrite core enters and exits from the same side of the ferrite core. In this case, the ferrite core noise reduction performance cannot be fully exhibited.
・ Because the ferrite core is fitted from the side of the board, the places where noise countermeasures are possible are limited.

  Furthermore, the structure disclosed in Patent Document 1 does not find any solution for the problem that current waveform inspection using a probe is difficult.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a printed circuit that can easily perform noise countermeasures using a ferrite core and current waveform inspection using a probe.

  In order to solve the above problems, the present invention is a printed circuit having a wiring formed on a printed circuit board, wherein the wiring is divided at a specific portion of the printed circuit board, and the two divided parts are A through-hole is formed so as to be sandwiched from both sides by the wiring, and the two separated wirings are connected by a wire provided so as to straddle the through-hole so that conduction is obtained. It is characterized by being.

  According to said structure, since the wire is arrange | positioned so that it may straddle on a through-hole in the specific location of a printed circuit, when performing a current waveform inspection using a probe in this specific location, this wire It is possible to easily inspect the probe by hooking the tip of the probe. Also, unlike a conventional lead wire, a wire can be connected between two separated wires in a straight line with the shortest path, and an inductance component is generated by the connection with the wire. Can be avoided. Therefore, it is possible to avoid the deterioration of the performance of the electronic circuit in the printed circuit.

  The printed circuit may be configured such that an annular ferrite core is disposed inside the through hole, and the wire is passed through the ring of the ferrite core.

  According to the above configuration, the ferrite core is not divided but an integrated ferrite core can be used. Therefore, magnetic flux leakage as in the case of using a divided ferrite core does not occur, and an efficient noise reduction effect can be obtained using a small ferrite core. Moreover, in a printed circuit, it can suppress that a printed circuit becomes tall by arrange | positioning a ferrite core inside a through-hole.

  In the printed circuit, the ferrite core has a fixing rib provided so as to protrude from the outer surface thereof, and the ferrite core fixes the fixing rib to an edge of the through hole. Thus, it can be configured to be fixed to the printed circuit board.

  According to said structure, a ferrite core can be fixed to a printed circuit board, avoiding a contact with a ferrite core and a wire. For this reason, when a vibration is given to a printed circuit etc., it can prevent that a ferrite core collides with a wire and gives stress.

  In the printed circuit, the through hole has an overhanging portion that protrudes inside the through hole in a plan view, and the ferrite core is held in a state where the overhanging portion is inserted in the ring. Can be configured.

  According to the above configuration, since the overhang portion is inserted into the ring of the ferrite core, the movement of the ferrite core (movement in the direction perpendicular to the axis of the ferrite core) is greatly limited by the overhang portion. Thereby, a ferrite core can be hold | maintained to a printed circuit board, suppressing the contact with a ferrite core and a wire. For this reason, when a vibration is given to a printed circuit etc., it can control significantly that a ferrite core collides with a wire and gives stress. In addition, the ferrite core can be held while having the merit that the shape of the ferrite core is simple and the mounting is easy because no screwing is required, and the cost can be reduced due to this merit.

  The printed circuit of the present invention can be easily inspected by hooking the tip of the probe on a wire when performing a current waveform inspection using a probe at a specific location. It is also possible to arrange a ferrite core and take measures against noise through a wire in the ring of the ferrite core. At this time, the wire can be linearly connected between the two separated wirings by the shortest path, and it is possible to avoid the generation of an inductance component due to the connection with the wire. There is an effect that it is possible to avoid the deterioration of the circuit performance.

3 is an enlarged perspective view showing a specific portion of the printed circuit according to Embodiment 1. FIG. FIG. 6 is an enlarged perspective view illustrating a specific portion of a printed circuit according to a second embodiment. The specific location of the printed circuit which concerns on Embodiment 3 is expanded and shown, (a) is a perspective view, (b) is AA sectional drawing of (a). FIG. 3 shows an enlarged view of a specific portion of a printed circuit according to Embodiment 4, wherein (a) is a plan view of the printed circuit before attaching the wire and the ferrite core, and (b) is after attaching the wire and the ferrite core. (C) is a BB sectional view of (b), (d) is a modification of (b), and is a plan view of the printed circuit after attaching a wire and a ferrite core. . It is a perspective view which shows the attachment method of the ferrite core in the conventional printed circuit.

[Embodiment 1]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an enlarged perspective view showing a specific portion (characteristic portion) in the printed circuit 10 according to the first embodiment. The specific location shown in FIG. 1 is preferably applied to a wiring location where a relatively large current flows in the printed circuit 10. Further, such a specific location is not limited to one location in the printed circuit 10, and a plurality of locations may exist.

  As shown in FIG. 1, the printed circuit 10 has a wiring 12 patterned on a printed board 11 by photolithography, printing, or the like. The wiring 12 is divided at a specific location of the printed circuit 10, and a through hole 13 is formed at the division location. The two separated wirings 12 are arranged so as to sandwich the through hole 13 from both sides.

  Further, the two separated wirings 12 are connected by wires 14 so as to straddle the through-holes 13 to obtain conduction. In FIG. 1, the divided wirings 12 are connected by three wires 14, but the number of wires 14 is not particularly limited.

  In addition, it is preferable to use a jumper wire for the wire 14. Some jumper wires can be used by inserting (inserting) a U-shaped wire into a substrate like a staple, and it is preferable to use such a jumper wire for the wire 14. However, the present invention is not limited to this, and both ends of the wire 14 may be connected to the wiring 12 with solder or the like.

  Since the wire 14 is disposed so as to straddle the through hole 13 at a specific location of the printed circuit 10, when performing a current waveform inspection using a probe at this specific location, It can be easily inspected by hooking the tip.

  Further, unlike the conventional lead wire (lead wire 110 in FIG. 5), the wire 14 can linearly connect the two separated wirings 12 with the shortest path. It is possible to avoid the generation of an inductance component due to the connection at. Therefore, in the printed circuit 10, it is also possible to avoid a decrease in the performance of the electronic circuit.

[Embodiment 2]
FIG. 2 is an enlarged perspective view showing a specific portion of the printed circuit 20 according to the second embodiment. In the printed circuit 20, the same components as those in the printed circuit 10 according to the first embodiment are denoted by the same member numbers, and the description thereof is omitted.

  The printed circuit 20 has a configuration in which a ferrite core 21 for noise suppression is added to the printed circuit 10 of the first embodiment. The ferrite core 21 is formed in an annular shape, and the wire 14 passes through the annular shape. The ferrite core 21 is disposed inside the through hole 13.

  As a procedure for attaching the ferrite core 21 in the printed circuit 20, the wire 14 before being connected to the printed board 11 may be passed through the ferrite core 21 and the wire 14 passed through the ferrite core 21 may be connected to the printed board 11. Alternatively, only one end of the wire 14 may be connected to the printed circuit board 11, and the other end may be passed through the ferrite core 21, and then the other end may be connected to the printed circuit board 11.

  In the printed circuit 20 according to the second embodiment, since the ferrite core 21 can be retrofitted after passing through the wire 14, the ferrite core 21 can be an integral type ferrite core instead of being divided. Therefore, magnetic flux leakage as in the case of using a divided ferrite core does not occur, and an efficient noise reduction effect can be obtained using a small ferrite core. Moreover, in the printed circuit 20, it can suppress that the printed circuit 20 becomes tall by arrange | positioning the ferrite core 21 inside the through-hole 13. FIG.

  In FIG. 2, the ferrite core 21 is illustrated as an annular shape, but the present invention is not limited to this. The ferrite core 21 only needs to be formed in an annular shape, and may have any other shape such as an elliptical ring shape or a rectangular ring shape.

[Embodiment 3]
3 is an enlarged view of a specific portion of the printed circuit 30 according to the third embodiment. FIG. 3A is a perspective view, and FIG. 3B is a cross-sectional view taken along line AA in FIG. In the printed circuit 30, the same components as those in the printed circuit 20 according to the second embodiment are denoted by the same member numbers, and the description thereof is omitted.

  The printed circuit 30 has a configuration in which the ferrite core 21 is changed to the ferrite core 31 in the printed circuit 20 of the second embodiment. The ferrite core 31 has a shape similar to the ferrite core 21, but has fixing ribs 32 for fixing the ferrite core 31 to the printed circuit board 11.

  The fixing rib 32 protrudes from the outer surface of the ferrite core 31 and has a screw hole for screwing. Thereby, the ferrite core 31 can be fixed to the printed circuit board 11 by screwing the fixing rib 32 on the edge of the through hole 13.

  In the printed circuit 30, as shown in FIG. 3B, the ferrite core 31 can be fixed to the printed board 11 while avoiding contact between the ferrite core 31 and the wire 14. For this reason, when the vibration is given to the printed circuit 30, it can prevent that the ferrite core 31 collides with the wire 14 and gives a stress. That is, when the stress from the ferrite core 31 is applied to the wire 14, it is possible to prevent a problem that the connection between the wire 14 and the wiring 12 is disconnected.

  The method for fixing the fixing rib 32 to the edge portion of the through hole 13 is not limited to the above-described screwing, and any other method such as soldering or adhesion can be used.

[Embodiment 4]
4 is an enlarged view of a specific portion of the printed circuit 40 according to the fourth embodiment. FIG. 4A is a plan view of the printed circuit 40 before the wire 14 and the ferrite core 21 are attached. FIG. Is a plan view of the printed circuit 40 after the wire 14 and the ferrite core 21 are attached, (c) is a sectional view taken along the line BB of (b), and (d) is a modification of (b), in which the wire 14 and the ferrite are provided. It is a top view of the printed circuit 40 after attaching the core 21. FIG. In the printed circuit 40, the same components as those in the printed circuit 20 of the second embodiment are denoted by the same member numbers, and the description thereof is omitted.

  The printed circuit 40 has a configuration in which the shape of the through hole provided in the printed board 11 is changed in the printed circuit 20 of the second embodiment. That is, in the printed circuit 40, a through hole 41 is formed at a part where the wiring 12 is divided. The divided two wires 12 are arranged so as to sandwich the through hole 41 from both sides.

  As shown in FIG. 4A, the through hole 41 has an overhanging portion 42 that protrudes inside the through hole 41 in plan view. The overhang portion 42 is formed so as to protrude opposite the inner side of the through hole 41 on two sides facing each other in the extending direction of the wiring 12 arranged with the through hole 41 interposed therebetween.

  As shown in FIG. 4B, the ferrite core 21 disposed inside the through hole 41 is held in a state where the tip of the overhanging portion 42 is inserted into the ring. The ferrite core 21 can be attached to the printed circuit 40 by the following procedure. First, one end of the ferrite core 21 is inserted into the one overhanging portion 42 in a state where the central axis of the ferrite core 21 is inclined with respect to the printed circuit board 11. Thereafter, the central axis of the ferrite core 21 is returned to be parallel to the printed circuit board 11 and attached so that the other end of the ferrite core 21 is inserted into the other overhanging portion 42.

  In order to enable the attachment, the ferrite core 21 and the through hole 41 satisfy the following dimensional conditions. That is, the length of the ferrite core 21 in the axial direction is L1 (see FIG. 4B), the distance between the two protruding portions 42 facing each other is L2 (see FIG. 4A), and the length of the protruding portion 42 is. Is L3 (see FIG. 4A), L2 <L1 <L2 + L3 is satisfied.

  In the printed circuit 40, as shown in FIG. 4C, the protrusion 42 is inserted into the ring of the ferrite core 21 so that the ferrite core 21 moves (moves in a direction perpendicular to the axis of the ferrite core 21). ) Is greatly limited by the overhanging portion 42. Accordingly, the ferrite core 21 can be held on the printed circuit board 11 while suppressing contact between the ferrite core 21 and the wire 14. For this reason, when the vibration is given to the printed circuit 40, it can suppress significantly that the ferrite core 21 collides with the wire 14, and gives a stress.

  The ferrite core 21 in the printed circuit 40 is not completely fixed to the printed circuit board 11 like the ferrite core 31 in the printed circuit 30, and the stress suppressing effect on the wire 14 is lower than that of the printed circuit 30. It becomes. On the other hand, compared with the printed circuit 30, there are advantages that the shape of the ferrite core 21 is simple and that screwing is not required, so that the mounting is easy, and cost reduction due to this advantage is expected.

  4 (a) and 4 (b), the overhanging portions 42 are provided at two locations with respect to one through hole 41. However, the present invention is not limited to this, and FIG. As shown, the overhang portion 42 may be provided at one location with respect to one through hole 41.

  The embodiments disclosed herein are illustrative in all respects and do not serve as a basis for limited interpretation. Therefore, the technical scope of the present invention is not interpreted only by the above-described embodiments, but is defined based on the description of the scope of claims. Further, all modifications within the meaning and scope equivalent to the scope of the claims are included.

10, 20, 30, 40 Printed circuit 11 Printed circuit board 12 Wiring 13, 41 Through hole 14 Wire 21, 31 Ferrite core 32 Fixing rib 42 Overhang portion

Claims (4)

A printed circuit having wiring formed on a printed circuit board,
The wiring is divided at a specific portion of the printed circuit board, and a through hole is formed so as to be sandwiched from both sides by the two divided wirings,
2. The printed circuit according to claim 1, wherein the two separated wirings are connected by a wire provided so as to straddle the top of the through-hole, and conduction is obtained. The printed circuit according to claim 1,
An annular ferrite core is disposed inside the through-hole, and the wire is passed through the ring of the ferrite core. The printed circuit according to claim 2,
The ferrite core has a fixing rib provided protruding from the outer surface thereof,
The printed circuit according to claim 1, wherein the ferrite core is fixed to the printed circuit board by fixing the fixing rib to an edge of the through hole. The printed circuit according to claim 2,
The through hole has a projecting portion that projects to the inside of the through hole in plan view,
The printed circuit according to claim 1, wherein the ferrite core is held in a state where the protruding portion is inserted in the ring.

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