JPH06112345A - Method and structure for packaging high-frequency integrated circuit - Google Patents

Abstract

PURPOSE:To prevent characteristics from being changed when a cover is closed, in regard to a case for a high-frequency integrated circuit. CONSTITUTION:A lump-shaped projection 5 formed of a metal block of a conductor, solder or the like is provided inside a metal case 1 for accommodating a high-frequency integrated circuit 7 and a board 2 whereon the circuit is mounted, and thereby the case 1, the integrated circuit 7 and a grounding circuit of the board 2 are connected together. By this constitution, a grounding surface in the case 1 is changed, and when a cover 8 is put on the case 1, the characteristics thereof change little.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mounting method and a mounting structure for a high frequency integrated circuit, and more particularly to a case structure using microwaves.

[0002]

2. Description of the Related Art As shown in FIGS. 3 (a) and 3 (b), a conventional high-frequency integrated circuit mounting structure has a substrate 2 having wirings for transmission lines and components, and an integrated circuit arranged on the substrate 2. The circuit 7, the chip capacitor 4 and the feedthrough capacitor 3 connected to the power supply terminal of the integrated circuit 7, the case 1 for housing the substrate 2, the lid 8 attached to the case 1 for electromagnetic shielding, and the inside of the case 1. And an RF connector 6 for connecting the outside and the outside. Grounding is performed by connecting to the case 1 through a through hole 2c opened in the substrate 2 on which the integrated circuit 7 is arranged. Next, characteristic examples will be shown. FIG. 4 shows the S parameter characteristics of this conventional mounting structure. The solid line is the S21 characteristic without the lid 8, and the broken line is the characteristic with the lid 8.

[0003]

In this conventional mounting structure, the lid is closed for electromagnetic shielding because the grounding through the through hole of the substrate is not perfect and the insulation between the input and output is incomplete. Then, there is a problem that the characteristics change before the lid is closed.

[0004]

SUMMARY OF THE INVENTION According to the present invention, an integrated circuit for inputting and outputting a high frequency signal is mounted on a substrate on which transmission lines and wirings for components are formed, and these integrated circuits are integrated with an external electromagnetic field. In a method of mounting a high frequency integrated circuit housed in a case that eliminates the correlation between the integrated circuit and the ground pattern of the substrate of the integrated circuit, a conductor lump member is provided to connect the case and the electromagnetic field of the input / output of the integrated circuit It is designed to reduce binding.

Further, the present invention provides a substrate on which wirings for transmission lines and parts are formed, an integrated circuit mounted on the substrate for inputting and outputting high frequency signals, and an external electromagnetic circuit including the substrate and the integrated circuit. In a mounting structure of a high-frequency integrated circuit including a case that eliminates correlation with a field, a lump member made of a conductor is provided inside the case, and is connected to the case, the integrated circuit, and a ground pattern of the substrate. ing.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention (a) is a plan view,
2B is a sectional view taken along the line AA of FIG. 2A, and FIG. 2 is a graph showing the S21 characteristic of one embodiment of the present invention.

As shown in FIG. 1, the structure of this embodiment is such that a ceramic substrate 2 provided with electrical wiring for a transmission line or a component is placed in a case 1 made of metal and having a block shape. Connect with solder. Further, an RF connector 6 for inputting / outputting a high frequency signal and a feedthrough capacitor 3 for removing noise of a power source are connected to the case 1. Ceramic substrate 2
The integrated circuit 7 is arranged on the upper side, and the chip capacitor 4 is attached to the power supply terminal of the integrated circuit 7. A microstrip line, a power supply terminal wiring and a ground plane are provided on the substrate 2, and a pattern 2a is provided on the front surface of the substrate 2 and a part of the pattern 2a is connected to the back surface by a through hole 2b.

Inside the case 1, a metal block-shaped projection 5 made of a conductor and forming a rectangular parallelepiped is provided. Part of the lower part of the protrusion 5 is in contact with the grounding pattern 2a on the substrate 2, and the upper two sides of the protrusion 5 are in contact with the two wall surfaces of the case 1.

That is, the case 1, the protrusion 5, the pattern 2a of the substrate 2 and the lower pattern of the integrated circuit 7 are all electrically connected. Finally, the lid 8 is fixed to the upper surface of the case 1 with screws.

By providing the projection 5 as described above,
The grounding ground is reinforced, the shape of the waveguide (cavity) formed when the lid 8 is closed can be reduced, and the cutoff frequency of the waveguide can be increased. As a result, as shown in the S21 characteristics of this embodiment in FIG. 2, the solid line shows the case without the lid and the broken line shows the case with the lid. In this embodiment, the projection 5 is illustrated as a metal block shape, but it may be a solder mass shape.

[0011]

As described above, the present invention has an effect that the change in the characteristics due to the presence or absence of the lid can be reduced by providing the conductor-like lump-shaped projection in the case and changing the grounding portion.

[Brief description of drawings]

FIG. 1A is a plan view showing an embodiment of the present invention,
(B) is the sectional view on the AA line of the same figure (a).

FIG. 2 is a graph showing S21 characteristics according to an example of the present invention.

FIG. 3A is a plan view showing an example of a conventional mounting structure;
(B) is a sectional view.

FIG. 4 is a graph showing S21 characteristics according to a conventional example.

[Explanation of symbols]

 1 Case 2 Substrate 3 Feedthrough Capacitor 4 Chip Capacitor 5 Protrusion 6 RF Connector 7 Integrated Circuit 8 Lid

Claims (3)

[Claims] 1. An integrated circuit for inputting and outputting a high-frequency signal is mounted on a substrate on which transmission lines and wirings for parts are made, and the integrated circuit is housed in a case that eliminates the correlation with an external electromagnetic field. In the mounting method of a high frequency integrated circuit, a block member of a conductor for connecting the case and the ground pattern of the substrate of the integrated circuit is provided to reduce electromagnetic field coupling between input and output of the integrated circuit. A method for mounting a high-frequency integrated circuit, characterized by: 2. A substrate on which wirings for transmission lines and components are formed, an integrated circuit mounted on this substrate for inputting and outputting high frequency signals, and an external electromagnetic field including the substrate and the integrated circuit. In a packaging structure of a high-frequency integrated circuit including a case that eliminates the correlation, a lump member made of a conductor is provided inside the case and connected to the case, the integrated circuit, and the ground pattern of the substrate. Characteristic high-frequency integrated circuit mounting structure. 3. The mounting method and mounting structure for a high frequency integrated circuit according to claim 1, wherein the block member is a metal block or a solder block.