JPH045883A - Installing device for component - Google Patents

Abstract

PURPOSE:To arrange a resistor in close proximity to an IC terminal, and to exchange the resistor easily by installing a mounting frame, to which a resistor housing hole is bored, and a cover, etc., to which a projection corresponding to the resistor housing hole is formed. CONSTITUTION:Chip type resistors 10 having a resistance value equal to the characteristic impedance of conductive patterns 2 formed are inserted to the input terminals of a flat type IC 4, impedance of which must be matched. Resistor housing holes 7 are bored to a mounting frame 5 fixed onto a substrate by screws 6 for fixing so as to surround the outer circumference of the IC 4, and the cover 11 of a conductor is fastened to the upper section of the mounting frame 5 by mounting screws 12. Projections 13 corresponding to the holes 7 are formed to the cover 11, and connected mechanically and electrically to the resistors 10 while other end faces of the resistors 10 are also connected mechanically and electrically to the leads of the IC 4. The resistors 10 constitute a terminal circuit in three dimensions by the leads of the IC 4 or the patterns 2 bonded with the leads and the frame 5, thus increasing the packaging density of components, then improving high-frequency characteristics and simplifying the exchange of the components.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to component mounting of a small electronic component mounting circuit using a flat IC, and particularly relates to a device for mounting components such as a terminating resistor. be.

(Prior art) Conventionally, impedance matching has been used to transmit signals in circuits that operate at high speed in order to avoid damaging high frequency characteristics.
A technique for terminating a transmission line with a resistance value equal to the characteristic impedance of the transmission line is known. FIG. 5 is an example of a circuit connection diagram using this technique. In Figure 5, input terminal 1
The circuit element 15 and the circuit element 18 having 4 are connected to the signal transmission line 16.
It is connected by The terminating resistor 17 has a value equal to the characteristic impedance of the signal transmission path 16, and by arranging the terminating resistor 17 near the input terminal of the circuit element 18, the high frequency characteristics of this circuit are maximized. By the way, FIG. 6 is a diagram showing an example of mounting a terminating resistor in a high-speed circuit using a conventional flat type IC. In Figure 6, 2
Reference numeral 4 denotes a transmission path pattern formed on the surface of the printed circuit board, to which the input end of the flat IC 21 is connected by soldering. Reference numeral 22 denotes a chip resistor used as a terminating resistor, which is connected by soldering between a terminating potential electrode 23 drawn out from another conductor layer of the printed circuit board and a transmission path pattern 24 to form a high-speed signal transmission circuit. There is.

(Problems to be Solved by the Invention) The above-described mounting method for terminating resistors has the problem that each terminating resistor requires a mounting area on the printed circuit board, which reduces the mounting density of components.

Furthermore, in some cases, such as when the input terminals of a flat IC are arranged adjacent to each other, the terminating resistor cannot be placed close to the IC terminals due to the mounting area, resulting in the problem that the high frequency characteristics cannot be bulky.

Furthermore, since the terminating resistor is attached by soldering, there is also the problem that it is difficult to replace the terminating resistor even if it turns out that the characteristic impedance of the conductor pattern is different from the originally planned value.

The present invention has been made in order to solve the above-mentioned problems, and in order to achieve the above-mentioned objects, the present invention has a number of components that allow a resistor to be placed close to an IC terminal and that allows the resistor to be easily replaced. The component mounting device according to the invention includes a resistor arranged to be connected to an IC lead or a transmission line pattern connected to the lead, and a resistor housing having a structure in which the resistor is housed in a direction perpendicular to the lead or transmission line pattern. The conductive part connects the other end of the inserted terminating resistor to the terminating potential.

(Function) According to the component mounting device of the present invention, the terminating resistor component can be arranged three-dimensionally in a direction perpendicular to the printed circuit board, so almost no mounting area is required, and the entire circuit can be mounted with high density. Furthermore, since the terminating resistor can be placed on the IC lead or on a nearby pattern, ideal impedance matching can be achieved without any negative effects on the wiring due to the routing of extra conductive patterns.

Furthermore, since the terminal resistor is not connected by soldering, parts can be easily replaced when changing the resistance value.

(Embodiment) FIGS. 1, 2, and 3 show an embodiment of the terminating resistor mounting device according to the present invention, and FIG. 1 is a cross-sectional perspective view (FIG. 2 A-A' part), and Figure 2 is its plan view (
FIG. 3 is a sectional view of the main part (section BB' in FIG. 2).

On the surface of the printed circuit board 1, a conductive pattern 2 and an IC connection pad 3 are formed, which are mechanically controlled to have a constant characteristic impedance using copper foil or the like. Flat type I
The lead wire of C4 is attached to the printed circuit board 1 by soldering to an IC connection pad.

The mounting frame 5 is fixed onto the substrate with fixing screws 6 so as to surround the outer periphery of the flat IC 4. This mounting frame 5 has a resistor housing hole 7 formed at a position facing the flat IC 4. Further, in a part of the mounting frame 5, a conductor 9 is formed up to the upper part of the mounting frame so as to be in contact with a terminal potential pattern 8 formed in advance on a printed circuit board using copper foil or the like.

Here, a conductive pattern 2 is formed on the input terminal of the flat IC 4 that requires impedance matching.
A chip resistor 1 with a resistance value equal to the characteristic impedance of
0 (hereinafter referred to as resistance) is inserted. A lid 11 made of a conductive material such as metal is fixed to the upper part of the mounting frame 5 with mounting screws 12. The lid 11 is provided with a protrusion 13 corresponding to the resistor housing hole 7, and is mechanically and electrically connected to the resistor 10. At the same time, the other end surface of the resistor 10 is mechanically and electrically connected to the lead of the flat IC 4. electrically connected. This protrusion 13 allows the resistor 10 to be mechanically and electrically connected to the lid 11 and the leads of the flat IC 4 more reliably.

In this embodiment, a cylindrical chip-type resistor is used, but other shapes such as a rectangular shape may be used as long as the shape of the resistor storage hole 7 of the mounting frame 5 is changed. Also, depending on the distance between the conductor patterns 2, the resistor housing holes 7 are arranged alternately in the mounting frame 5.
It can also be provided in

FIG. 4 shows a second embodiment of the component mounting device according to the present invention, which is compatible with a flat type IC4 with short leads. Here, the shape of the mounting frame is changed so that instead of the IC lead (B) that one end of the chip-type resistor 10 was in contact with in the first embodiment, the lead contacts the conductive pattern 2 that is soldered. It has been changed.

(Effects of the Invention) As described above, according to the component mounting device of the present invention, the terminating resistor is three-dimensionally terminated by the mounting frame housed perpendicularly to the lead of the flat IC or the conductive pattern connected to the lead. By configuring the circuit, we have achieved a significant increase in component mounting density, improved high frequency characteristics, and ease of component replacement.

[Brief explanation of drawings]

1, 2, and 3 are views showing one embodiment of the component mounting device according to the present invention, FIG. 4 is a sectional view showing the second embodiment, and FIG. 5 is a diagram showing the transmission line without closing it. The connection diagram and FIG. 6 are plan views of a conventional terminating resistor mounted. 1... Printed circuit board, 2... Conductive pattern, 4...
・Flat type IC, 5... Mounting frame, 8... Terminating potential button, 10... Chip type resistor, 11... Lid.

Claims (1)

[Claims] (1) Consisting of a resistor arranged to be connected to an IC lead or a transmission line pattern connected to the lead, a resistor storage part that stores this resistor, and a conductive part connected to the potential to which the resistor is connected. Parts mounting device.