JPH0247939A - Module structure for digital multiplexer - Google Patents

Abstract

PURPOSE:To attain high density mount and ease of handling by forming an idle area of an opposite board so as to arrange an oscillator with shield case and a filter with shield case mutually. CONSTITUTION:A large scale integrated circuit LSI for multiplexer is mounted on the center of one side A of a circuit board I and an oscillator VCO with shield case is arranged to the surrounding of other side B. Small sized parts SMD being components of the circuit are mounted on one side A of a circuit board 11 and a filter FIL with shield case is arranged in the middle of the other side B. Moreover, the boards I, II are arrange closely while the faces B are faced in parallel so that the FIL enters the middle space of the VCO. Then the circuits of the boards I, II are connected electrically and the boards are stood upright on a module board 25 and connected and the entire module is covered by a metallic case 30.

Description

[Detailed Description of the Invention] [Summary] Regarding the module structure of a digital multiplexer, an object of the present invention is to configure modules compactly, achieve high-density mounting, and obtain a module structure of a digital multiplexer that is easy to handle. A large integrated circuit for a multiplexer is mounted in the center of one side of the first circuit board, and an oscillator with a shield case is arranged around the other side,
Small components constituting the circuit are mounted on one side of the second circuit board, and a filter with a shield case is placed in the center of the other side, and the first and second circuit boards are arranged so that the filter fits into the center space of the oscillator. two circuit boards are arranged in parallel with their other surfaces facing each other in close proximity to each other, and the circuits of the first and second circuit boards are electrically connected to stand upright on the module board. The module structure of the digital multiplexing device is characterized in that the digital multiplexing device is connected and mounted and covered with a metal case.

[Industrial application field]

The present invention relates to a module structure for electronic equipment, communication equipment, etc., and particularly to a module structure for a digital multiplexer.

The digital multiplexing device (M13 type multiplexer or converse demultiplexing device demultiplexer) used in the above equipment, for example, converts a primary group in the 1.5 MHz band to a tertiary group in the 45 MHz band, and is used in the subscriber system. Demand is increasing due to digitization (direct communication on a small-capacity scale without going through a switching center) and the introduction of large-capacity optical transmission lines. This type of digital multiplexing device is usually divided into units of a low-order group (ie, a low-speed group that handles a low frequency range) and units of a high-order group (that is, a high-speed group that handles a high frequency range). in this way,
A digital multiplexing device that includes low-order and high-order groups can be densely packaged to reduce the size of the device without causing electrical or mechanical interference between the devices and components of the low-order and high-order groups. required.

[Conventional technology]

Figure 8 is an external view of a conventional digital multiplexer (M13 type multiplexer) seen from the front, and Figure 0, which constitutes one system of the same M13 type multiplexer, is a standardized shelf-type housing. , which extends to the back of the page, shows a state in which a printed board is inserted from the front into a backboard on the back, plug-in connection is made, and a front board is attached to the front of the board.

Part A of FIG.
z band primary conversion, 6 MHz band secondary conversion) unit, the printed board package (Figure 9) is mounted vertically, and is composed of seven identical packages arranged horizontally in parallel, each with one package. are 4 channels each (C old ~ CH4,
CH5 to CH8,...), and a total of 28 channels are configured in one system. The interval at which one package is arranged, that is, the package pitch is T (T = 15.24
m). This pitch T is the maximum height H (H=8.5■■
) is determined based on the required dimensions.

In FIG. 8, section B is a spare low-order group puff cage housing section, and section C accommodates two high-order group printed board packages. Part D is a power supply package accommodating part, and the power supply is duplicated and consists of two packages. Section E is a control section, which houses a circuit pancase along with operating parts for control, display parts, alarms, and the like.

A side view of the printed board pancage of the low-order group is shown in FIG. The board of package l is a printed board, and on the front side there are four ammunition jacks 2 connected to the sight measuring device.
and four B/U units 3 toward the back side,
A mechanical filter (FIL) 4 and a voltage controlled oscillator (VCO) 5 are arranged in series, and one LSI 6 is further mounted.

7 is a plug-in connector for plug-in connection to the backboard, and 8 is a lever-type extractor for pulling out the package 1 from the shelf.

[Problem to be solved by the invention]

As shown in Figures 8 and 9, in the conventional digital multiplexing device where one component unit consists of one printed circuit board package and one system consists of seven packages, mounting efficiency can be improved. In order to achieve this, the pitch T between each package should be made as small as possible, but this pitch is limited by the maximum height of components mounted in one package, so it has been difficult to increase mounting efficiency. . In addition, seven identical printed board packages were required only for the low-order group (M12).

Accordingly, the present invention provides a digital multiplexing device that is configured compactly by modularizing, for example, low-order groups (M12-1st order, 2nd order conversion) in a digital multiplexing device, achieves high-density packaging, and is easy to handle. The aim is to obtain a modular structure.

[Means to solve the problem]

A large integrated circuit for a multiplexer is mounted in the center of one side of the first circuit board, and an oscillator with a shield case is placed around the periphery of the other side, and a circuit is configured on one side of the second circuit board. At the same time, a filter with a shield case is placed in the center of the other surface, and the first and second circuit boards are placed between the other surfaces of the oscillator so that the filter fits into the central space of the oscillator. The first and second circuit boards are arranged in parallel and close to each other facing each other, and the circuits of the first and second circuit boards are electrically connected, and the circuits are connected and mounted upright on the module board, and covered with a metal case. A modular structure of a digital multiplexer featuring features is provided.

[For production]

According to the present invention, the oscillator with a shield case and the filter with a shield case, which do not interfere with each other electrically or mechanically, are arranged so as to form an empty area of the mating board, so that the space inside the metal case is eliminated. will be used effectively and implementation efficiency will be improved. In addition, by mounting multiple modules configured in this way on the same printed board to configure one package, it is possible to
In the present invention, it is possible to configure one system with one buff cage.

〔Example〕

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

FIG. 1 is a block diagram of one module of a digital multiplexing device according to an embodiment of the present invention, that is, a low-order group (M12-first order, second order transform) module, and FIG. 2 is a block diagram of two modules constituting the same module. FIG. 2 is a layout diagram of components mounted on two substrates, that is, a ceramic substrate (2) and a resin substrate (2). This example is
For example, a resin substrate is used as the substrate for the primary group (low speed) that uses the 1.5 MHz band for each channel, and a ceramic substrate is used as the substrate for the secondary group (high speed) that uses the 6 MHz band after multiplexing. The L module constitutes 4 channels.

The resin board (■) is made of a glass fiber-containing epoxy or Teflon resin board with a board thickness of about 1.6 fins, and one side (A) has 4 channels of identical circuits B101 to B.
/U4 blocks are formed for each unit, and various chip components SMD are mounted in each circuit area. Other side (B)
At the center of the filter, four mechanical filters FILL to FIL4 with identical shield cases are arranged corresponding to the channels. A chip component SMD is a so-called surface mount component whose surface is molded and does not have leads etc. Therefore, it can be mounted directly onto the circuit pattern on the surface of the board with solder etc. without using through holes on the board. be. On the other hand, as shown in FIG. 3, the mechanical filters FILI to FIL4 are shield components whose outsides are covered with a metal shield case 10, and have a plurality of leads 11 to 14. Therefore, the through hole 15 of the board is used to connect and mount the circuit on the A side. Since there is nothing other than chip components SMD and patterns in the center of side A of the resin board ■ (opposite side of the mechanical filter), mechanical filters FILI~F
IL4 can be inserted through hole 1 without being obstructed by other parts.
It can be implemented using 5. Note that the chip component SMD can be appropriately placed in a region other than the through hole 15 for mounting the mechanical filter.

The ceramic substrate I has a thickness of, for example, about 0.8 mm, and one large integrated circuit LSI for a multiplexer is mounted in the center of one surface (A), and four large integrated circuit LSIs are mounted on the periphery of the other surface (B). The voltage controlled oscillators VCOI to VCO4 are arranged so as to be located at each corner. Large integrated circuit LSI
It is also a chip component and does not have leads, so it is mounted directly onto the circuit pattern on the board with solder or the like without using through holes on the board.

On the other hand, voltage controlled oscillator VCOI with shield case
Like a mechanical filter, the VCO 4 is a shield component whose outside is covered with a metal shield case 10 as shown in FIG. 3, and has a plurality of leads 11 to 14. Therefore, it is connected and mounted to the circuit on side A using the through hole 16 of the board at a peripheral position avoiding the large integrated circuit LSI on the opposite side. Note that various chip components SMD are also arranged around the large integrated circuit LSI on the A side of the ceramic substrate r.

Figure 3 shows the mechanical filter FILL-FIL4 mentioned above.
It also shows voltage controlled oscillators VCOI to VCO4, where IO is a metal case for shielding, 11-14 are leads, for example 11 is used for input, 12 is used for output, 13 is used for grounding, and boards After mounting on each board I,
Connected to the signal, power supply pattern, and ground pattern (not shown) of the circuit (2). All such lead components can be of the same size, for example 20X20X10 (height) fl, but other surface mount chip components SM
It is considerably larger and taller than D.

Therefore, the mechanical filters FILL to FIL4 and the voltage controlled oscillators vcoi to VCO4 are constructed by placing the substrates ■ and ■ with their eight sides facing inward, as shown in FIG.
For example, when they are arranged in parallel with an interval of about 12 to 13+n, they are arranged so that they do not enter into each other's space and interfere with each other.

Figure 4 is a cross-sectional view of the module of the example, and Figure 5 is the board.
, (2), and FIG. 6 is an exploded perspective view of the assembled module of the embodiment. The circuit of board ■, ■, i.e. 2
The circuits on the next group (high speed) side and the circuits on the first group (low speed) side are connected by hard connection lead pins 20. Furthermore, channels CIA and CIIB in FIG. 1 are connected by a hard input/output pin 21. These input/output leads 21 are connected to a flexible printed board insertion hole 23 via a pattern 22 on the board (2), and are connected to a terminal 26 of a connector housing 25, which is a module board, via a flexible printed board 24. The boards (2) and (2) are covered with a metal case 30 that is attached to the module board.
It is composed of four dragon-sized modules 40.

In FIG. 7, a plurality of modules 40 configured as described above, for example, seven modules, are mounted vertically on a printed board package 50 to configure a digital multiplexing device with one system and 28 channels. This printed board package 50
is approximately the same size as the conventional one shown in FIG. 9, which is, for example, 220 x 230 am. In the free space on the printed circuit board package, circuits such as a high-order group main signal section and a high-order group switch (SW) section for multiplexing the third order group are separately mounted from the module 40 of the present invention to form one system. A modular power supply for one system will also be implemented. This puff cage 50 can be inserted into a shelf (not shown).
Plugin implemented. In FIG. 7, 51 is a connector that fits into the shelf-side motherboard (not shown) when the package 50 is inserted, and 52 is a lever-type extractor that facilitates insertion and removal into the shelf (not shown). , 53 are pedestals provided on the pan cage 50 for plug-in connection and fixing of the module 40 with screws. In the above embodiment, seven four-channel modules 40 are mounted on the package 50, but the number of channels per module and the number of modules mounted on one package can be selected as appropriate according to the specifications of the multiplexer. Needless to say, Shiroko.

The package 50 is a conventional package A, B, C, etc. shown in FIG.
It has the function of part D. Therefore, by mounting the pitch of 50 cranes in the space of the A-D portion, a large number of systems can be mounted on one shelf. This means that extremely high-density packaging is now possible.

〔Effect of the invention〕

According to the present invention as described above, modules of a digital multiplexer can be configured compactly and with high density. For example, the conventional M12 shown in FIG.
Compared to conventional digital multiplexing equipment, one module is constructed from one printed board package, and the shelf width T per package is 15.24 mm.
In order to mount 7 packages, approximately 100 cranes are required, which is 7 times as many. However, in the embodiment of the present invention, 7 packages can be mounted in one package, and the height of one package is equal to the height of the module 40. Since only a little more than 44 m, which corresponds to 44 m, is required, the space required to configure one system of M12 type digital multiplexing equipment is small, and high density can be achieved. Furthermore, since each system mounted on the package 50 can be inserted into and removed from the shelf, handling becomes easy. In addition, in the present invention, for each module, the primary group side and the
Since the next group side and the two boards I and (2) are spaced apart from each other and the circuit pattern A side is brought closer to the shield case 40, there is no risk of signal crosstalk. A digital multiplexer is obtained. It would be even better if all eight sides were grounded except for the main parts. The substrate of the present invention is not limited to a resin substrate or a ceramic substrate, and may be implemented in any combination.

[Brief explanation of the drawing]

FIG. 1 shows a digital multiplexing device according to an embodiment of the present invention.
Figure 2 is a block diagram of the two modules; Figure 2 is a layout of components on the two boards that make up the module; Figure 3 is a perspective view of lead components with shield cases such as mechanical filters and voltage control oscillators; The figure is a cross-sectional view of the module of the embodiment, FIG. 5 is a diagram showing the connection of the two boards I and (2) constituting the module, FIG. 6 is an exploded perspective view of the module of the embodiment in an assembled state, and FIG. 7 FIG. 8 is a front view of a conventional digital multiplexer, and FIG. 9 is a side view of a conventional low-order group package. ■... Ceramic board (first circuit board), ■...
Resin board (circuit board in Figure 2), LSI...large integrated circuit for multiplexer, ILL...mechanical filter with shield case, vCO...voltage control oscillator with shield case, SMD...chip parts, lO
...Metal shield case, ■1-14...Lead, 15.16...Through hole, 20...Connection lead pin, 21...Input lead bin, 22...
Pattern, 23...Flexible printed board insertion hole, 24...
Flexible printed board, 25... Contact housing, 26... Terminal, 30... Metal case, 4
0...Module, 50...Package. Cross-sectional view of the module of the embodiment FIG. 4 Substrate 1. [Connection of 1 Fig. 5 Exploded diagram of Mononil Fig. + 17CO... Voltage control oscillator 40 mounts Monoe 50... Panokeno Front view of conventional multiplexing device Fig. 17

Claims (1)

[Claims] 1. A large integrated circuit (LSI) for a multiplexer is mounted in the center of one side (A) of the first circuit board (I), and an oscillator with a shield case (VC@) is mounted around the other side (B). O@) and place the second circuit board (II)
Small components (SMD) that constitute a circuit on one side (A) of
At the same time, a filter with a shield case (FIL) is placed in the center of the other surface (B), and the above oscillator (
The first and second circuit boards are placed on the other side (B
) placed in parallel and close to each other, facing each other;
Furthermore, the digital multiplexing device is characterized in that the circuits of the first and second circuit boards are electrically connected, the circuits are connected and mounted upright on the module board (25), and the circuits are covered with a metal case (30). modular structure.