JPH066550Y2 - Microwave / millimeter wave module structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] The present invention relates to an integrated circuit of a wireless device, and more particularly to a microwave / millimeter wave module structure in which conduction of a ground side circuit is taken into consideration. Circuit parts are provided on a dielectric plate. In a microwave / millimeter-wave circuit module that is surface-mounted and has microstrip lines and circuit elements connected by patterning, and the bottom surface serves as the ground plane and is closely fixed to one surface of the metal base, The bottom part of the lower surface near the output terminals or the input / output connection part of the pattern end (hereinafter abbreviated as the connection terminal) is convex than the other bottom surface including the side surface, and does not require any additional work when fixing the module. , Is connected to the shortest structural distance without variation and can be applied up to the maximum frequency.

[Industrial application field]

The present invention relates to an integrated circuit used in a wireless device, and more particularly to a microwave / millimeter wave module structure in consideration of conduction of a ground side circuit.

Circuit components such as semiconductor components are surface-mounted on a dielectric plate, and microstrip lines, other transmission lines, and circuit elements are patterned and connected, and the other surface is used as a ground plane and fixed to one side of the housing metal case. The microwave / millimeter wave integrated circuit configured as described above is now indispensable for the construction of the microwave / millimeter wave wireless device.

The frequency also becomes smaller as the frequency becomes higher, and by modularizing each circuit function to generalize and standardize, it is possible to combine these modules and bring them together to exert a predetermined integrated function. It has become necessary for cost reduction.

[Conventional technology]

FIG. 3 shows a conventional microwave module, and FIG. 4 shows a connection cross-sectional view of the module.

This example has a structure of a module 51 in which a circuit component is hermetically sealed. A metal base 32 that also serves as a ground side circuit and for heat dissipation has a bottom surface as a flat surface, and a circuit component 9 at the center of the surface. A circuit board 1 which is surface-mounted and on which a pattern 2 having a desired circuit configuration and a strip conductor 1A is formed is adhered and fixed by a conductive adhesive or the like. The heat-generating component 91 is a direct metal base.
The heat transfer is fixed to 32 and the connection wire 7 is used to connect to the circuit board 1.

In order to hermetically seal this circuit constituent part, an insulating frame 8 is provided on the opposite side surface through which the connection terminal 4 is penetrated airtightly, and both end surfaces are metallized, and a metal lid 10 for covering the end surface is used. The insulating frame 8 is welded to the central portion of the base 32, the circuit board 1 and the heat-generating component 91 are fixed therein, and one end of the connection terminal 4 penetrating the insulating frame 8 and the strip conductor 1A of the circuit board 1 are connected. , And finally weld the metal lid 10 to the end face of the insulating frame 8,
It is hermetically sealed.

The module that does not require hermetic sealing of the circuit components does not use the insulating frame 8 and the metal lid 10 described above, and is directly connected to the pattern 2 of the circuit board 1 with the outside.

These modules 51 are collected and connected to form a large circuit unit.

As shown in FIG. 4, the cross-sectional state of this connection is such that the connection circuit portion of the unit has a structure in which the circuit board 11 on which the circuit is formed is adhered on the ground board 31, and the strip conductor 21 of the circuit board 11 is connected. The end portion and the connection terminal 4 of the module 51 are connected to each other. On the ground circuit side, the module 51 is placed at a predetermined position on the ground substrate 31 of the unit and fixed by screwing or the like.
This is performed by electrically connecting the bottom surface of the metal base 32 to the ground substrate 31.

[Problems to be solved by the invention]

However, as shown in FIG. 4, (1) the bottom surface of the metal base 32 and the surface of the ground substrate 31 should ideally be in full contact with each other when they are fixed, and it is necessary that both surfaces have sufficient flatness.

(2) However, in reality, unspecified partial contact occurs. For example, the contact is made at the AB portion of the end directly below the connection terminal 4, or the first contact is made at the recessed CD portion. The ground side circuit length L transmitted on the surface of the stand 32 or the ground substrate 31 varies and affects the transmission characteristics, and when 2L = 1/2 wavelength, the ground surface to be grounded is opened and the transmission characteristics are adversely affected. Exert.

Therefore, it is necessary to use at L << 1/4 wavelength.

(3) As for the influence of the above item (2), since the L value is related to the wavelength, the application of the module 51 having the same structure to higher frequencies is limited.

(4) In order to avoid this, fixing work has been performed with great care, such as sandwiching a metal foil so as to fill the gap between the contact surfaces or providing a conductive coating film. There were problems such as.

SUMMARY OF THE INVENTION The present invention provides a microwave / millimeter wave module structure for eliminating the variation in characteristics due to the above problems and making it possible to apply the same module structure up to the maximum high frequency band.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides the method shown in FIGS.
As shown in the figure, a circuit board 1 having a microwave / millimeter wave circuit and a strip conductor on the front surface, a metal base 3 on which the back surface of the circuit board 1 is closely adhered to mount the circuit board 1, and a metal base. The metal base 3 so that it protrudes in the side direction of the base 3.
And a microwave / millimeter wave connection terminal 4 for connecting one end to a strip conductor, the metal base 3 being screwed and mounted on the ground substrate 31 surface. The bottom surface portion 6 of the metal base 3 directly below the connection terminal 4 is formed to be a convex surface including the side surface of the metal base 3.

[Action]

That is, on the ground side of the connection with the outside, the convex part provided on the metal base surely contacts and is connected in the shortest time, so there is no variation and the maximum frequency determined by the shortest distance can be applied, and the purpose can be achieved. .

The high frequency circuit of the module 5 is generally connected by a microstrip line.

This is a strip conductor formed on the surface of the circuit board 1.
1A and a ground plane conductor (upper surface of the metal base 3) on the back side of the dielectric substrate (circuit board 1), and electromagnetic waves are concentrated and transmitted near the strip conductor on the strip conductor and the plane conductor. .

Although it is the same at the connection end, as shown in the connection cross-sectional view of FIG. 2, the conductor connection on the ground side is made by bringing the bottom surface of the metal base 3 of the module 5 into contact with the surface of the mating ground substrate 31. In the present invention, since the bottom surface portion 6 of the metal base 3 directly below the strip conductor 1A, that is, directly below the connection terminal 4, is made to be more convex than the other surface, the module 5 can be mounted at a predetermined position on the ground substrate 31 and fixed. In this case, the bottom surface portion 6 of the convex surface is preferentially brought into contact with each other, so that the portion AB in FIG. 2 can always be surely conducted.

The shortest distance of the ground circuit length L of the connection part is the gap G of the connection end part.
As long as it is present, conduction is established at the AB portion.

Therefore, the module 5 structure has the shortest connection,
It will be applicable up to the maximum frequency that is characteristically allowable.

Thus, the incompleteness of the structure and processing of the connection part between the module and the other party can eliminate the effect on the electrical characteristics, eliminate the variation in the characteristics due to the connection, and make it possible to apply up to the maximum frequency determined by the structure. You can

〔Example〕

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

Throughout the drawings, the same reference numerals indicate the same symmetrical objects.

FIG. 1 (a) is a top perspective view of an embodiment of the present invention, FIG. 1 (b) is a bottom perspective view thereof, and FIG. 2 is a connection sectional view of a module of the present invention.

The present embodiment has a structure of the module 5 in which the same circuit components as in the above-mentioned conventional example are hermetically sealed.

However, the bottom surface of the metal base 3 that also serves as a ground side circuit and for heat dissipation is not a single plane, and the bottom surface portion 6 immediately below the connection terminal 4 that is connected to the outside is partially convex from the other bottom surface. is there.

Others are the same as the conventional example, and the circuit component 1 is surface-mounted on the central portion of the surface of the metal base 3, and the circuit board 1 on which the pattern 2 and the strip conductor 1A having a desired circuit configuration are formed is formed on the surface. , Are fixed by adhesion with a conductive adhesive or the like. Further, the heat generating component 91 is directly heat-fixed to the metal base 3 and connected to the circuit board 1 by using the connecting wire 7.

In order to hermetically seal this circuit constituent part, an insulating frame 8 is provided on the opposite side surface through which the connection terminal 4 is penetrated airtightly, and both end surfaces are metallized, and a metal lid 10 for covering the end surface is used. The insulating frame 8 is welded to the central portion of the base 3, the circuit board 1 and the heat-generating component 91 are fixed therein, and one end of the connection terminal 4 penetrating the insulating frame 8 and the strip conductor 1A of the circuit board 1 are connected. , And finally weld the metal lid 10 to the end face of the insulating frame 8,
It is hermetically sealed.

The module 5 is connected to the strip conductor on the connection terminal 4 and the mating circuit board 11 as shown in the connection sectional view of FIG.
21 is welded to each other, and the conductor connection on the ground side is performed by fixing the bottom surface of the metal base 3 of the module 5 to the surface of the grounding substrate 31 of the other party. At this time, the convex bottom surface portion 6 is preferentially contacted. However, when there is a gap G at the connection end, it is possible to always ensure reliable conduction between the AB portion having the ground circuit length L of the connection portion as the shortest distance.

The bottom surface portion 6 is formed by partially cutting the bottom surface of the metal base 3 into a convex shape by cutting or pressing.

Although the above embodiment shows the module hermetically sealed, the circuit connection on the ground side can be applied to the module which is not sealed in the same manner as described above.

Further, the outer shape of the module and the number of connection terminals are not limited to those shown in the figure.

[Effect of device]

As described above, the impedance mismatch at the microwave / millimeter wave connection point is reduced, and the incompleteness of the structure and processing of the connection portion between the module and the counterpart can eliminate the influence on the electrical characteristics. It is possible to eliminate variations in characteristics due to connection without applying special work when fixing the module, and to make it possible to apply up to the maximum frequency determined by the structure, which has a great effect.

[Brief description of drawings]

 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a connection sectional view of a module of the present invention, FIG. 3 is a conventional microwave module, and FIG. 4 is a connection sectional view of a module. . In the figure, 1,11 is a circuit board, 2 is a pattern, 3,32 is a metal base, 4 is a connection terminal, 5,51 is a module, 6 is a bottom part, 7 is a connection wire, 8 is an insulating frame, and 9 is Circuit parts, 10 is a metal lid, 21 is a strip conductor, 31 is a ground substrate, and 91 is a heat-generating component.

Claims (1)

[Scope of utility model registration request] 1. A circuit board (1) having a microwave / millimeter wave circuit and a strip conductor on the surface, and the circuit board (1) on the upper surface.
A metal base on which the back side of the circuit board (1) is mounted in close contact
(3) and a microwave / millimeter wave connection terminal (4) that is supported above the metal base (3) so as to project in the side direction of the metal base (3) and that has one end connected to the strip conductor. ) And
In a microwave / millimeter wave module in which the metal base (3) is mounted by screwing on the surface of a grounding substrate (31), a bottom surface portion (6) of the metal base (3) immediately below the connection terminal (4). But,
A microwave / millimeter wave module structure comprising a convex surface including the side surface of the metal base (3).