JP2003168523A - Flexible printed wiring board connectors - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To provide a connector for a flexible printed wiring board capable of transmitting a high frequency band (for example, 3 GHz) without crosstalk between adjacent signal lines. A plurality of signal lines arranged in parallel on one surface of a flexible insulating layer and ground portions formed on the other surface of the insulating layer in opposition to the signal lines, and adjacent to each other. (1) using a flexible printed wiring board including a plurality of auxiliary conductors arranged between the signal lines to be arranged and arranged inside or on the surface of the insulating layer and electrically connected to the ground. A shield plate (2) covering almost the entire surface, a signal terminal (4) for contacting each signal line of the flexible printed wiring board, and a ground terminal (3) for contacting each auxiliary conductor and the shield plate of the flexible printed wiring board. Characterized by the following structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connector for high frequency transmission using a flexible printed wiring board (FPC) in which a plurality of signal lines are arranged in parallel, and more particularly to a flexible connector in which impedance matching, crosstalk and skew are reduced. The present invention relates to a wiring board connector.

[0002]

2. Description of the Related Art Various measuring instruments, high-resolution LCD (Liquor)
In the wiring field of equipment that uses high-speed digital transmission and analog transmission such as an id crystal display device, it is necessary to improve the function of the transmission line along with the high-speed transmission technology that is currently increasing in speed. .

However, when using a flexible printed wiring board and a connector whose impedance is matched,
Due to poor high-frequency performance of the connector, there were obstacles such as narrow transmission band and large crosstalk, which was a barrier to use. Further, the connector structure for a flexible printed wiring board having conductors on both sides adopts a method of connecting the conductors on both sides of the flexible printed wiring board, so that the structure is complicated, the cost is high, and the quality is stable. It was a wall.

[0004]

A cross-sectional view of the signal terminal portion of the connector 100 used for the flexible printed wiring board 105 can be that shown in FIG. The flexible printed wiring board connector 100 shown in FIG. 6 is composed of a shield plate 101, a housing 102, a signal terminal 103, and a slider 104, which are substantially entirely covered with the connector. In the example shown in FIG. 6, the signal terminal 103 is in contact with the signal line arranged on one surface of the flexible printed wiring board 105, and the shield 101 is in contact with the ground portion provided on the other surface of the flexible printed wiring board 105. Therefore, the line impedance in the connector portion depends on the electrostatic capacitance between the signal terminal 103 and the shield plate 101. Therefore, in order to match the line impedance with the characteristic impedance of the flexible printed wiring board 105, the distance between the signal terminal 103 and the shield plate 101 needs to be substantially equal to the thickness of the insulating layer of the flexible printed wiring board 105. However, due to the structure, the distance becomes large, the line impedance of the connector portion becomes larger than the characteristic impedance of the flexible printed wiring board 105, and an electrical failure occurs. Further, the electrical length of the circuit of each signal terminal 103 is different, and the skew becomes large. Furthermore, the signal terminal 103 is electrically flexible from the adjacent signal terminal 103, and the crosstalk becomes large and the high frequency performance deteriorates. At the same time, the slider 104 presses the signal terminal 103, so that the signal terminal 103 is surely flexible. Signal line and signal terminal 10 of the printed wiring board 105
Since 3 cannot contact, reliability is lost.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art and to provide a connector for a flexible printed wiring board capable of high frequency transmission.

[Means for solving the problem]

In order to achieve the above object, a connector for a flexible printed wiring board according to the present invention includes a shield plate that covers substantially the entire surface of the connector, a signal terminal that contacts individual signal lines of the flexible printed wiring board, and an individual flexible printed wiring board. And a ground terminal that comes into contact with the shield plate.

With this structure, since the signal terminal and the ground terminal are in contact with the signal line and the auxiliary conducting wire arranged on one surface of the flexible printed wiring board, the structure of the connector is simplified. The line impedance of the connector portion depends on the electrostatic capacitance between the signal terminal, the ground terminal and the shield plate. Moreover, since the surface areas of the signal terminal and the ground terminal can be changed arbitrarily, the sum of the capacitance between the signal terminal and the ground terminal and the capacitance between the signal terminal and the ground terminal can be adjusted, and the line impedance of the connector section can be adjusted to the flexible printed wiring board. It can be adjusted to the characteristic impedance of. In addition, the electrical length of the flexible printed wiring board consisting of signal lines and signal terminals is substantially equal to the electrical length of the flexible printed wiring board ground portion and auxiliary conductors and ground terminals. Becomes smaller. Furthermore, since the signal terminal of the connector section is surrounded by the ground terminal and the shield plate, it is possible to prevent the occurrence of crosstalk between a plurality of signal lines.

In addition, a connector using a flexible printed wiring board is provided with one or more signal terminals that come into contact with the individual signal lines of the flexible printed wiring board, and at least one ground terminal that comes into contact with an auxiliary line of the flexible printed wiring board and a shield plate. Characterized by structure.

As a result, when the pitch between the signal terminals of the connector becomes small, the resin housing becomes thin and it becomes difficult to form the shape. Therefore, instead of contacting each auxiliary conductor with the ground terminal, by arranging the ground terminal in contact only with the auxiliary conductor on the outside of the flexible printed wiring board, the distance between the signal terminals can be increased and the manufacturing is easy. Becomes In that case, when the present inventor actually measured, in the band from DC to 2 GHz,
The line impedance of the connector is about 60 against the characteristic impedance of the flexible printed wiring board of 50Ω.
Ω, skew about 160ps, crosstalk 30d
BWR or more and VSWR are 1.5 or less, and it has been proved that high frequency transmission is possible.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a flexible printed wiring board connector according to the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of the connector 1 for a flexible printed wiring board according to one embodiment of the present invention as seen from above, and FIG. 2 is a flexible printed wiring board 5.
3 is a plan view seen from the upper surface of FIG. 3, FIG. 3 is a plan view seen from the lower surface of the flexible printed wiring board 5, and FIG. 4 is a cross-sectional view of the signal line circuit portion of the flexible printed wiring board connector 1. 5 is a cross-sectional view of the ground portion of the flexible printed wiring board connector 1.

As shown in FIG. 2 or 3, the flexible printed wiring board 5 has a plurality of signal lines 7 arranged in parallel on one surface side of the insulating layer and the insulating layer and the other surface side of the insulating layer. It is provided with a ground portion 8 and a plurality of auxiliary conducting wires 6 that are electrically connected to the ground portion 8. As shown in FIG. 1, FIG. 4 or FIG. 5, the signal line of the flexible printed wiring board 5 is in contact with the signal terminal 4, and the ground terminal 3 is in contact with the shield plate 2 and the flexible printed wiring board 5. When the flexible printed wiring board 5 is fitted into the connector 1, the slider 11 holds the flexible printed wiring board 5. The housing 10 holds and fixes the shield plate 2, the signal terminal 4 and the ground terminal 3. The signal circuit portion is composed of the signal line 7 of the flexible printed wiring board 5 and the signal terminal 4 of the connector 1, and the ground circuit portion is the portion 9 that connects the ground portion 8 of the flexible printed wiring board 5 and the ground portion 8 to the auxiliary conductor 6. And the ground terminal 3 in contact with the shield plate 2. The portion of the flexible printed wiring board 5 is adjusted so that broadband transmission can be performed, and in the connector 1 portion, the characteristic impedance between the signal terminal 4 and the ground terminal 3 and the shield plate 2 is adjusted by adjusting the shapes of the signal terminal 4 and the ground terminal 3. By doing so, it is possible to match the line impedance of the flexible printed wiring board 5 portion. Further, since there is almost no difference in electrical length between the signal circuit portion and the ground circuit portion, the skew can be made small enough to be ignored.
Further, since the signal terminal 4 is surrounded by the ground terminal 3 and the shield plate, it is possible to reduce crosstalk in each signal circuit portion in the connector portion.

The ground terminal 3 may be one step away from the auxiliary conductor 6 or two points at both ends, although the wide band castle transmission is slightly reduced.

As described above, in the present invention, the connector 1
Of the shield plate 2 covering almost the entire surface of the signal terminal 4 and the signal terminals 4 contacting the individual signal lines of the flexible printed wiring board 5
And the individual auxiliary conductors 6 of the flexible printed wiring board 5
Also, since the ground terminal 3 that contacts the shield plate 2 is provided, the characteristic impedance of the connector 1 can be matched with the line impedance of the flexible printed wiring board 5, and the generation of crosstalk between adjacent signal circuits can be effectively performed. In addition to being able to prevent it, skew and external noise can be reduced.

[0015]

As described above, according to the configuration of the present invention, the characteristic impedance in the connector portion can be matched with the line impedance of the flexible printed wiring board, and the occurrence of crosstalk between a plurality of signal circuits can be effectively prevented. However, it is possible to reduce skew and reliably perform transmission in a high frequency band. Further, since the connector is a contact type that can be contacted from one side, the structure is simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a plan view of a connector for a flexible printed wiring board according to the present invention viewed from above.

FIG. 2 is a plan view of a flexible printed wiring board according to the present invention seen from above.

FIG. 3 is a plan view of a flexible printed wiring board according to the present invention viewed from the lower side.

FIG. 4 is a sectional view of a signal terminal portion of a connector for a flexible printed wiring board according to the present invention.

FIG. 5 is a cross-sectional view of the ground terminal portion of the flexible printed wiring board connector according to the present invention.

FIG. 6 is a sectional view of a signal terminal portion of a conventional flexible printed wiring board connector.

[Explanation of symbols]

1 Flexible Printed Wiring Board Connector 2 Shield Board 3 Ground Terminal 4 Signal Terminal 5 Flexible Printed Wiring Board 6 Flexible Printed Wiring Board Auxiliary Lead 7 Flexible Printed Wiring Board Signal Line 8 Flexible Printed Wiring Ground 9 Flexible Printed Wiring Board The part that connects the grounding part to the auxiliary conductor 10 Housing 11 Slider

Claims (2)

[Claims] 1. A plurality of signal lines arranged in parallel on one surface of a flexible insulating layer, and a ground portion formed on the other surface of the insulating layer so as to oppose the signal lines. In a connector using a flexible printed wiring board, which is disposed between the respective adjacent signal lines and is arranged inside or on the surface of the insulating layer and arranged and which is provided with the plurality of auxiliary conducting wires that are electrically connected A shield plate that covers almost the entire surface of the connector, a signal terminal that contacts each of the signal lines of the flexible printed wiring board, and a ground terminal that contacts each of the auxiliary conducting wires and the shield plate of the flexible printed wiring board. A flexible printed wiring board connector with a built-in structure. 2. A connector using the flexible printed wiring board, wherein a signal terminal that contacts each of the signal lines of the flexible printed wiring board and a ground that contacts the auxiliary line of the flexible printed wiring board and the shield plate. Flexible printed wiring board connector with a structure equipped with one or more terminals.