JP3770413B2 - Anti-static structure of through connector board - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a static electricity preventing structure for a through connector substrate into which input / output terminals of the through connector are inserted.
[0002]
[Prior art]
Some electronic units include a plurality of printed wiring boards arranged in a stacked state, and include a through connector that penetrates the printed wiring boards at the same time, thereby forming an integrated unit that integrates the plurality of printed wiring boards at high density. In such an electronic unit, an antistatic structure may be provided to protect the internal circuit from static electricity applied to the input / output terminals. An example of this type of antistatic structure provided with a capacitor as an electrostatic absorption component will be described with reference to FIGS. FIG. 3 is a circuit diagram showing an example of wiring of a conventional antistatic structure, and FIG. 5 is a plan view showing an example of a substrate configuration by the circuit of FIG.
[0003]
The through-connector substrate (substrate) 1 has a slit-like long hole 3, and the through-hole 5 of the through connector is inserted into the long hole 3. The through terminal 5 penetrates the substrate 1 and is then inserted into another substrate that is stacked. A plurality of branch terminal lands 7 are provided on both sides of the elongated hole 3 in the longitudinal direction of the elongated hole, and a branch terminal (not shown) of a through connector is inserted and connected to the branched terminal land 7. A chip capacitor 11 is connected to each branch terminal land 7 provided on one side of the long hole 3 via a pattern wiring 9, and the chip capacitor 11 is connected to the ground pattern 13 and the ground through hole 15 on the substrate 1. And connected.
[0004]
In such a conventional antistatic structure, the branch terminal land 7 is connected to the ground pattern 13 or the like via the chip capacitor 11, so that the static electricity applied to the through connector is absorbed to the ground pattern 13 side. It prevented the destruction of electrical components that are vulnerable to static electricity.
[0005]
[Problems to be solved by the invention]
However, since the chip capacitor 11 is provided for each branch terminal land 7 in the conventional structure, the chip capacitor 11 is required corresponding to the number of through connectors, the number of parts increases, the cost increases, A space for installing the chip capacitor 11 is also required, and there is a problem that it becomes an obstacle to downsizing of the substrate. In addition, the electrostatic absorption method using the chip capacitor 11 can withstand static electricity of a certain voltage, but if it exceeds that, absorption becomes difficult, and there is a possibility that the wiring pattern and the electrical parts in the substrate may be discharged. there were.
The present invention has been made in view of the above situation, and provides an antistatic structure for a through-connector board that can protect an internal circuit without adding an electrostatic absorption component such as a capacitor. The purpose is to remove the obstacles to miniaturization and improve the electric resistance.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the structure of the antistatic structure according to the present invention includes a through connector board on which a ground pattern is formed, an elongated hole formed in the through connector board for inserting a through terminal of the through connector, A wiring pattern that surrounds the hole and is connected to the ground pattern and has a resist coated on the surface thereof, and is formed on the opposite side of the elongated hole across the wiring pattern and is inserted through the branch terminal of the through connector A branch terminal land, and a conductor exposed portion facing the branch terminal of the through connector formed in the wiring pattern by removing the resist and straddling the wiring pattern. It is.
In the static electricity prevention structure configured as described above, when static electricity is applied to the through connector, the static electricity is discharged from the through connector to the ground level conductor exposed portion before flowing into the internal circuit, and is provided inside the electronic unit. Static electricity does not flow to the IC. Further, static electricity is directly discharged to the ground pattern of the printed wiring, and the withstand voltage is higher than that in the case of using an electrostatic absorption component.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of an antistatic structure according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view of a main part showing an antistatic structure according to the present invention, and FIG. 2 is a plan view of the main part of the antistatic structure according to the present invention.
The through-connector substrate (substrate) 21 is formed with a slit-like long hole 23 through which the through terminal 27 of the through-connector 25 passes. A loop-like wiring pattern 29 is formed on the substrate 21 so as to surround the long hole 23, and the wiring pattern 29 is connected to a ground pattern 31 on the substrate 21. The ground pattern 31 and the surface of the wiring pattern 29 are covered with a resist 33.
[0008]
A plurality of branch terminal lands 35 are provided in the longitudinal direction of the long hole 23 on the left and right sides of the wiring pattern 29 with the long hole 23 at the center. Accordingly, as shown in FIG. 1, in the through connector 25 in which the through terminal 27 penetrates the elongated hole 23, a pair of branch terminals 37 protruding from both sides are respectively inserted into the branch terminal lands 35 on both sides. .
[0009]
The through connector 25 forms a branch terminal 37 by bending the arm portion 41 protruding from both sides into an M shape on both sides of the base body 25a on which the through terminal 27 is suspended. Therefore, when the tip of the branch terminal 37 is inserted into the branch terminal land 35, the arm portion 41 is disposed in a state of straddling the left and right wiring patterns 29.
[0010]
The wiring pattern 29 is not covered with the resist 33, and a loop-shaped conductor exposed portion 45 is formed so as to surround the long hole 23 and the conductor portion of the wiring pattern is exposed. The conductor exposed portion 45 is formed to have a width of about 0.1 mm, for example, the width of the portion not covered with the resist 33. The conductor exposed portion 45 may be one in which solder is adhered in a thin line shape. The conductor exposed portion 45 is formed at a position where the solder bridge does not occur and is as close to the through connector 25 as possible, for example, the arm portion 41.
[0011]
In the static electricity prevention structure of the substrate 21 formed in this way, when the largest static electricity in terms of energy immediately after being discharged from the charged object is applied to the through connector 25, this static electricity flows through the internal connector 25 before flowing into the internal circuit. From the arm portion 41 or the branch terminal land 35 to the ground-level conductor exposed portion 45. As a result, destruction of electrical components sensitive to static electricity such as an IC provided inside the electronic unit is prevented.
[0012]
Further, in this static electricity prevention structure, static electricity is directly discharged to the ground pattern 31 of the printed wiring, so that the withstand voltage is higher than when a static absorption component such as a conventional chip capacitor is used.
[0013]
As described above, according to the above-described antistatic structure, it is not necessary to add static absorption parts such as a chip capacitor in addition to the parts constituting the centralized unit, so that the number of parts can be greatly reduced and the cost can be reduced. In addition, a space for disposing these static electricity absorbing parts is not necessary, and the substrate can be easily downsized. Furthermore, the electric resistance can be improved by directly discharging the ground pattern 31 of the printed wiring without using the electrostatic absorption component.
[0014]
In the above-described embodiment, the case where the conductor exposed portion 45 is formed in a loop shape surrounding the elongated hole 23 has been described as an example. However, the antistatic structure according to the present invention is connected to the ground pattern 31. As long as the conductor exposed portion 45 is formed close to the through connector 25 or the branch terminal land 35, the conductor exposed portion 45 is not necessarily a loop shape, and may be a C-shape, for example.
[0015]
FIG. 3 is a cross-sectional view of an essential part showing another embodiment of the antistatic structure according to the present invention. In this static electricity prevention structure, the above-described conductor exposed portion 45 is not formed on the substrate surface 21a on the through connector 25 insertion side, while the conductor exposed portion 47 is formed on the substrate surface 21b opposite to the through connector 25 insertion side. The conductor exposed portion 47 is connected to the ground pattern 31 and is formed at a position that is as close as possible to the branch terminal land 35 at a distance that does not cause a solder bridge.
In this static electricity prevention structure, as described above, when static electricity is charged in the through connector 25, static electricity is discharged from the branch terminal land 35 to the conductor exposed portion 47 at the ground level. As a result, destruction of electrical components sensitive to static electricity such as an IC provided inside the electronic unit is prevented.
[0016]
Although not shown, the antistatic structure according to the present invention forms the exposed conductor 45 on the board surface 21a on the insertion side of the through connector 25 and the conductor on the board surface 21b on the opposite side of the insertion side of the through connector 25. The exposed portion 47 may be formed.
With such a structure, the number of places where discharge is possible increases, so that the discharge can be made more reliable.
[0017]
【The invention's effect】
As described above in detail, according to the antistatic structure according to the present invention, the exposed conductor connected to the ground pattern of the substrate is made to face the branch terminal of the through connector arranged across the wiring pattern. Therefore, when static electricity is applied to the through connector, the static electricity can be discharged from the through connector to the ground level conductor exposed portion before the static electricity flows to the internal circuit. As a result, it is not necessary to increase the number of parts for absorbing static electricity, so that the number of parts can be greatly reduced, the cost can be reduced, and the space for arranging them can be eliminated, and the board can be easily downsized. Furthermore, since the static electricity is directly discharged to the ground pattern of the printed wiring, the electric resistance can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part showing an antistatic structure according to the present invention.
FIG. 2 is a plan view of an essential part of an antistatic structure according to the present invention.
FIG. 3 is a cross-sectional view of a main part showing an antistatic structure according to another embodiment.
FIG. 4 is a circuit diagram showing a wiring example of a conventional antistatic structure.
FIG. 5 is a plan view showing an example of a substrate configuration by the circuit of FIG. 4;
[Explanation of symbols]
31 Ground pattern 21 Through connector board (board)
25 through connector 27 through terminal 23 long hole 33 resist 29 wiring pattern 37 branch terminal 35 branch terminal land 45, 47 exposed conductor

Claims (5)

  A through connector board on which a ground pattern is formed, an elongated hole formed in the through connector board for inserting a through terminal of the through connector, and formed to surround the elongated hole and connected to the ground pattern and resisted on the surface Formed on the wiring pattern by removing the resist, the wiring pattern covered with the wiring pattern, the branch terminal land formed on the opposite side of the elongated hole across the wiring pattern, and the branch terminal of the through connector being inserted. A structure for preventing static electricity of a through connector board, comprising: a conductor exposed portion facing a branch terminal of the through connector disposed across the wiring pattern.   2. The structure for preventing static electricity of a through connector board according to claim 1, wherein the wiring pattern formed so as to surround the elongated hole and the conductor exposed portion are formed in a continuous loop shape.   A pair of branch terminal lands are provided in the minor axis direction of the elongated hole across the elongated hole, the pair of branch terminals are formed in the through connector, and the through terminal of the through connector is inserted into the elongated hole. 2. The electrostatic prevention of a through connector board according to claim 1, wherein each of the pair of branch terminals straddles the exposed conductor portion by inserting the pair of branch terminals into the branch terminal lands on both sides of the long hole. Construction.   A through connector board on which a ground pattern is formed, a branch terminal land provided on the through connector board for inserting and connecting a branch terminal of the through connector, and the ground pattern formed on the through connector board surface opposite to the branch terminal insertion side And a conductor exposed portion facing the branch terminal land exposed on the same substrate surface and exposed to the same. A second conductor exposed portion facing the branch terminal land formed on the through connector board surface opposite to the branch terminal insertion side and connected to the ground pattern and exposed on the same board surface; The structure for preventing static electricity of a through connector substrate according to claim 1 .

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