JPH09116510A - Interface module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the shape, to decrease the occupancy rate and to reduce crosstalk by forming a reception section and a transmission section as independent blocks and containing the reception section and the transmission section into a container section while opposing them to each other. SOLUTION: A reception section 2 and a transmission section 3 are respectively made up of a low pass filter, a pulse transformer T1 and a choke transformer or the like. Then the reception section 2 and the transmission section 3 are formed respectively to be independent blocks and printed circuit boards 12, 13 of the reception section 2 and the transmission section 3 are contained in a package while being stood upright symmetrically in the center of the package while being opposite to each other. Thus, the electric coupling between the reception section 2 and the transmission section 3 is reduced and the reception section 2 and the transmission section 3 are integrated without taking crosstalk into account. Furthermore, a shield member is arranged between the reception section 2 and the transmission section 3 to reduce more the mutual electric coupling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interface module, and more particularly to an interface module used for transmission of digital signals in LAN (local area network), computer-to-computer communication, data terminal communication, and the like.

[0002]

2. Description of the Related Art Conventionally, an interface circuit is used when transmitting a digital signal in LAN, communication between computers, communication between data terminals, etc., especially when low radiation noise from a transmission line is required. Is used. FIG. 7 is a circuit diagram showing a conventional interface circuit, where 1 is the whole interface circuit,
2 is a receiver, 3 is a transmitter, T1 and T2 are pulse transformers, T3 and T4 are choke transformers, 8 is a receiver, and 9 is a receiver.
Indicates a driver. Entire interface circuit 1
Is composed of a receiver 2 and a transmitter 3, and the receiver 2 includes a low-pass filter 4, a pulse transformer T1, and a choke transformer T.
3, the transmission unit 3 includes a low pass filter 5, a pulse transformer T2, and a choke transformer T4. The low-pass filter 4 removes noise (harmonic components) mixed in the transmission line, and the low-pass filter 5 is
This is to remove harmonic components (noise in normal mode). The pulse transformers T1 and T2 electrically separate the input side and the output side to insulate between the input and output, and the choke transformers T3 and T4 use the common mode noise (on the two lines with respect to the ground). The noise generated by the electric potential) is removed. It should be noted that R1 and R2 are matching resistors serving as a load of the receiving unit 2, and R3, R4, R5, R
Reference numerals 6 and R7 are resistors for shaping the waveform of the digital signal input to the transmitter 3. The signal on the receiving side has a waveform close to a sine wave, and after the common mode noise is removed by the choke transformer T3, the signal is converted by the pulse transformer T1 and the noise (harmonic component mixed in the transmission path by the low pass filter 4 is further added. ) Is removed and output to the receiver 8. Further, the signal input to the transmission side is a square wave digital signal, and this signal is input from the driver 9 to the low-pass filter 5 to remove the harmonic component and have a waveform close to a sine wave. Then, this signal is input to the choke transformer T4 via the pulse transformer T2, and common mode noise is removed.

In such an interface circuit, a plurality of inductors and capacitors forming a low-pass filter, electronic components such as a pulse transformer, a choke transformer, etc. are mounted on the same printed circuit board without distinguishing between the receiving section and the transmitting section. Are integrated.

[0004]

In recent years, in order to communicate between a plurality of computers and between a plurality of data terminals, a plurality of such interface circuits have been used to increase the number of interfaces of the interface. Therefore, the interface module that integrates the individual interface circuits reduces the occupied area and
It is desirable to keep crosstalk low. However, in the conventional interface module, the individual parts that make up the interface circuit are mounted on the printed circuit board without distinguishing the receiving part and the transmitting part, so the spacing between the individual parts is reduced in order to reduce the occupied area. When the width is narrowed, electrical coupling occurs between the receiving part and the transmitting part, so that the crosstalk cannot be suppressed low. In order to keep this crosstalk low, it is considered to form the receiving part and the transmitting part with separate composite parts, but two composite parts are required, and each composite part is placed on the printed circuit board of the interface. It is necessary to reduce the stray capacitance by separating the parts. Therefore, the occupying area becomes large, and it is not possible to mount the interface on the multi-channel type as described above. Also, in the interface where the number of channels has been advanced,
There is a problem in that a composite component having twice the number of channels is required and it becomes expensive. In order to reduce the occupied area, it is considered to form the receiving unit on one surface of the printed circuit board and the transmitting unit on the other surface of the printed circuit board. It was not possible to keep the crosstalk between the transmitters low.

It is an object of the present invention to provide an interface module which can suppress the crosstalk low even when the size is reduced and the occupied area is reduced.

[0006]

In the interface module of the present invention, the receiving unit and the transmitting unit are configured by a low-pass filter, a pulse transformer, a choke transformer, or a low-pass filter and a pulse transformer, respectively, and the receiving unit The transmitter and the transmitter are formed as independent blocks, respectively, and the receiver and the transmitter are opposed to each other and housed in a package. The receiving unit and the transmitting unit may be formed by forming the receiving unit and the transmitting unit on separate substrates so that the receiving unit substrate and the transmitting unit substrate face each other, or by forming them on one surface of the different substrates, respectively. The other surface of the formed substrate and the other surface of the substrate on which the transmitter is formed are brought close to each other via a shield member and housed in a package. In addition,
Here, the package includes a case and a resin mold for sealing the whole. In the interface module of the present invention, the receiving unit and the transmitting unit are configured by a low-pass filter, a pulse transformer, a choke transformer, or a low-pass filter, and a pulse transformer, respectively. The receiving part and the transmitting part are formed independently of each other, and the substrate is bent along the center line and accommodated in the package. further,
In the interface module of the present invention, a shield member is arranged between the receiver and the transmitter.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The receiving portion and the transmitting portion of an interface module may be formed on different substrates, or may be formed as separate blocks on both sides of the center line in the width direction of the substrate and bent at the center line. Then, the receiving unit and the transmitting unit are opposed to each other, and the substrate is stored in a package in an upright state. Therefore, the electrical coupling between the receiver and the transmitter can be reduced, and the receiver and the transmitter can be integrated without taking crosstalk into consideration as in the conventional case. Further, by disposing the shield member between the receiver and the transmitter, it is possible to further reduce the electrical coupling between the receiver and the transmitter.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an interface module of the present invention will be described below with reference to FIGS. FIG.
Is an exploded perspective view showing a first embodiment of the interface module of the present invention, and FIG. 2 is a sectional view taken along the line AB of FIG.
In FIGS. 1 and 2, 11 is a case, and 12 and 13 are printed circuit boards. The same parts as those in FIG. 7 are denoted by the same reference numerals. The interface module is the receiver 2
, A low pass filter 4, a pulse transformer T1,
The choke transformer T3 is mounted on both sides of the printed circuit board 12 to form a circuit block, and the low-pass filter 5, the pulse transformer T2, and the choke transformer T4 forming the transmitter 3 are mounted on both sides of the printed circuit board 13 to form a circuit block. Then, the receiver 2 and the transmitter 3 are housed in the case 11 and integrated. In the receiving unit 2, a part of the plurality of inductors L and capacitors C forming the low pass filter 4 and the pulse transformer T1 are mounted on one surface of the printed board 12, and the remaining part of the low pass filter 4 and the choke transformer T3. Is mounted on the other surface of the printed circuit board 12. Further, in the transmission unit 3, a part of the plurality of inductors L and capacitors C that form the low-pass filter 5 and the pulse transformer T2 are mounted on one surface of the printed circuit board 13, and the remaining part of the low-pass filter 5 and the choke. The transformer T4 is mounted on the other surface of the printed board 13. The case 11 is made of resin and has a bottom, and the holding portions 16A, 16B, 16C, 1
6D is provided. Holding portions 16A, 16B, 16
C and 16D are provided by forming a groove from the opening end side of the case 11 toward the bottom surface, and the holding portions 16A and 1D are provided.
6B and holding portions 16C and 16D are provided at positions facing each other. The printed circuit board 12 and the printed circuit board 13 are accommodated in the case 11 with a space therebetween in a state where they are erected so that their one surfaces face each other.
Are held by the holding portions 16A and 16B, and the printed circuit board 13 is held by the holding portions 16C and 16D. Reference numeral 17A denotes a plurality of metal plate terminals attached to the printed circuit board 12, and 17B denotes a plurality of metal plate terminals attached to the printed circuit board 13, which are respectively connected to the wiring pattern of the interface board.

FIG. 3 is a sectional view showing a second embodiment of the interface module of the present invention. In FIG. 3, 31 is a case and 32 and 33 are printed circuit boards.
The receiving unit 2 includes a pulse transformer T1 and a choke transformer T.
3 is mounted on one surface of the printed circuit board 32, and a plurality of inductors and capacitors C forming the low pass filter 4 are mounted on the other surface of the printed circuit board 32. Also,
The transmitter 3 includes a pulse transformer T2 and a choke transformer T.
4 is mounted on one surface of the printed circuit board 33, and a plurality of inductors and capacitors C forming the low pass filter 5 are mounted on the other surface of the printed circuit board 33. The printed circuit board 32 on which the receiving section 2 is formed and the printed circuit board 33 on which the transmitting section 3 is formed are positioned so as to be parallel to each other, and are housed in the case 31 with an interval. A shield plate 30 made of a conductor is arranged between the printed circuit boards 32 and 33. The shield plate 30 is
Grounded. Then, the shield plate 30 and the printed circuit board 3
2. The printed circuit board 33 is held by the holding portions 36 provided on the inner side surfaces of the case 31, respectively.

FIG. 4 is a sectional view showing a third embodiment of the interface module of the present invention. In FIG. 4, 41 is a case, and 42 and 43 are printed circuit boards.
In the receiving unit 2, a plurality of inductors and capacitors C, a pulse transformer T1, and a choke transformer T3 that form the low-pass filter 4 are mounted on only one surface of the printed board 42. Further, in the transmitting unit 3, the plurality of inductors and capacitors C, the pulse transformer T2, and the choke transformer T4 that form the low-pass filter 5 are mounted on only one surface of the printed circuit board 43. The other surfaces of the printed circuit board 42 and the printed circuit board 43 are bonded to the shield plate 40. Then, the printed boards 42 and 43 adhered to the shield plate 40 are stored in the storage portion 41 in an upright state, and are held by the holding portion 46 provided on the inner side surface of the storage portion 41. Is grounded. In this case, the distance between the two blocks is the smallest, and the interface module can be made compact.

FIG. 5 is a side view of a board in a fourth embodiment of the interface module of the present invention, and FIG. 6 is an exploded perspective view of the fourth embodiment. In FIGS. 5 and 6, 51
Is a case, and 52 is a flexible substrate. The receiver 2 and the transmitter 3 are separately formed on both sides of the center line E-F in the width direction of the film-shaped flexible substrate 52. In the pulse transformer T1, the choke transformer T3, and the low-pass filter 4 of the receiving unit 2, a plurality of inductors L and capacitors C that constitute the low-pass filter 4 are mounted on both surfaces of the substrate 52, and the pulse transformer T1 is on one surface and the choke transformer T1. T3 is mounted on the other side. Further, in the pulse transformer T2, the choke transformer T4, and the low-pass filter 5 of the transmitting unit 3, a plurality of inductors L and capacitors C that constitute the low-pass filter 5 are mounted on both surfaces of the substrate 52, and the pulse transformer T2 is on one surface, The choke transformer T4 is mounted on the other surface. The case 51 is made of resin and has a bottom, and a holding portion 56 is provided by forming a continuous projection on one side surface on the inside and the bottom surface.
Then, the flexible substrate 52 has the center line E- in the width direction.
The receiving portion 2 is bent by setting a predetermined space around F.
It is stored in the case 51 with the transmitting section 3 facing each other,
It is held by the holding unit 56. In addition, 67A is a plurality of metal plate terminals provided in the receiving unit 2, 67B is a plurality of metal plate terminals provided in the transmitting unit 3, and a plurality of metal plates are provided by filling the case 51 with resin. The terminal 67A and the plurality of metal plate terminals 67B are held at a predetermined interval. This interface module uses a film-shaped flexible board wound in a roll shape, and the film-shaped flexible board wound in a roll shape is pulled out so that the receiving section and the transmitting section of a plurality of interface modules are continuously connected. It is possible to form a plurality of interface modules, and by cutting the one in which the receiving portion and the transmitting portion are formed, the receiving portion and the transmitting portion of the plurality of interface modules can be formed at one time. Easy to do.

Although the embodiments of the interface module of the present invention have been described above, the present invention is not limited to these embodiments. For example, in the first, second, and third embodiments, the case may be filled with resin. Further, the substrate of the receiving unit and the substrate of the transmitting unit of the third embodiment may be arranged at positions close to each other via the shield plate without adhering to the shield plate. Furthermore, an insulating spacer can be used instead of the shield plate of the third embodiment. Furthermore, in the fourth embodiment, a plurality of cuts are provided on the side surface of the case from the opening end side to fix the metal plate terminal to the cuts, or a flexible substrate that holds the shape once bent is used. Good. In that case, the metal plate terminals of the receiving unit and the transmitting unit can maintain a predetermined distance even if the case is not filled with resin. The holding portion of the fourth embodiment may be one in which protrusions are formed separately, without being continuous with one inner side surface and the bottom surface. The receiving unit and the transmitting unit may be formed as independent blocks, and the arrangement positions of the pulse transformer, the choke transformer, and the inductors and capacitors of the low-pass filters forming the respective units can be arbitrarily changed. Further, the choke transformers of the receiving unit and the transmitting unit can be omitted when they are mounted outside the interface module or when the noise level is low. Further, instead of the resin case, a resin mold in which the entire metal plate terminals are sealed may be used. The number and shape of the metal plate terminals of the receiver and transmitter are
It can be changed arbitrarily.

[0013]

As described above, in the interface module of the present invention, the receiving section and the transmitting section are formed as independent blocks, respectively, and the receiving section and the transmitting section face each other and are stored in the storage section. Can be made smaller to reduce the space factor and the crosstalk can be kept low.

[Brief description of the drawings]

FIG. 1 is a first interface module of the present invention.
FIG. 3 is an exploded perspective view showing the embodiment of FIG.

FIG. 2 is a sectional view taken along a line AB in FIG.

FIG. 3 shows a second example of the interface module of the present invention.
It is sectional drawing which shows Example of (a).

FIG. 4 is a third example of the interface module of the present invention.
It is sectional drawing which shows Example of (a).

FIG. 5: Fourth interface module of the present invention
FIG. 6 is a side view of the substrate in the example of FIG.

FIG. 6 is a fourth example of the interface module of the present invention.
FIG. 3 is an exploded perspective view showing the embodiment of FIG.

FIG. 7 is a circuit diagram showing a conventional interface circuit.

[Explanation of symbols]

 2 receiver 3 transmitter 11 case 12 printed circuit board 13 printed circuit board

Claims (11)

[Claims] 1. A receiving unit and a transmitting unit each comprising at least a low-pass filter and a pulse transformer, and in an interface module in which these are integrated, the receiving unit and the transmitting unit are formed as independent blocks, respectively, and the receiving unit An interface module, characterized in that the transmission section and the transmission section face each other and are housed in a package. 2. A receiving unit and a transmitting unit each including at least a low-pass filter and a pulse transformer, and in an interface module in which these are integrated, the receiving unit and the transmitting unit are formed as independent blocks, respectively, and the receiving unit An interface module in which a transmitter and a transmitter are opposed to each other and housed in a case. 3. A receiving unit and a transmitting unit each including at least a low-pass filter and a pulse transformer, and in an interface module in which these are integrated, the receiving unit and the transmitting unit are formed on different substrates, and An interface module, characterized in that a board of a receiver and a board of the transmitter are opposed to each other and housed in a case. 4. An interface module in which a receiving section and a transmitting section each include at least a low-pass filter and a pulse transformer, and these are integrated, the receiving section and the transmitting section are formed on one surface of different substrates. At the same time, the other surface of the substrate on which the receiving unit is formed and the other surface of the substrate on which the transmitting unit is formed are brought close to each other via a shield member and housed in a case. 5. An interface module in which the receiving section and the transmitting section each include at least a low-pass filter and a pulse transformer, and these are integrated, the receiving section and the transmitting section are provided on both sides of the center line in the width direction of the flexible substrate. An interface module, which is formed independently, and is bent in the centerline and housed in a case. 6. A receiving unit and a transmitting unit each include at least a low-pass filter and a pulse transformer, and in an interface module in which these are integrated, the receiving unit and the transmitting unit are formed as independent blocks, respectively, and the receiving unit An interface module in which the transmitter and the transmitter are opposed to each other and sealed with a resin. 7. An interface module in which the receiving section and the transmitting section each include at least a low-pass filter and a pulse transformer, and the receiving section and the transmitting section are formed on different substrates in the interface module, and An interface module, characterized in that the substrate of the receiver and the substrate of the transmitter are opposed to each other and sealed with resin. 8. An interface module in which a receiving unit and a transmitting unit each include at least a low-pass filter and a pulse transformer, and these are integrated, the receiving unit and the transmitting unit are formed on one surface of different substrates. At the same time, the other surface of the substrate on which the receiving portion is formed and the other surface of the substrate on which the transmitting portion is formed are brought close to each other via a shield member and sealed with resin. 9. In an interface module in which the receiving section and the transmitting section each include at least a low-pass filter and a pulse transformer, and these are integrated, the receiving section and the transmitting section are provided on both sides of the center line in the width direction of the flexible substrate. An interface module, which is formed independently, and is bent at the center line and sealed with resin. 10. The interface module according to claim 1, wherein a shield member is arranged between the receiving unit and the transmitting unit. 11. The interface module according to claim 2, wherein the case is filled with resin.