JPH0249730Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Technical field of invention] The present invention relates to hybrid integrated circuits.

[Technical background of the invention and its problems] The container (package) for hybrid integrated circuits can be made of plastic filled with resin or ceramic, but especially when housing circuits related to high frequencies, metal can be used. is used. This is to shield the circuit.

By the way, when storing a circuit in a metal container,
It is necessary to fix a circuit board on which a circuit is formed to a metal container, and a method conventionally used for this fixing is to solder the back edge of the board to the container. For this reason, at least the edge of the back side of the board needs to be made of metal so that it can be soldered. Conventionally, the circuit shield was also layered to form a ground electrode on the entire back side of the board, and only the area around the lead wire was insulated. I took it.

However, according to the above configuration, when the back side edge of the board and the metal container are soldered, since the entire back side of the board is a ground electrode, the melted solder flows and spreads unnecessarily. There is a problem in that solder workability is very poor because the solder does not rise sufficiently on the edge of the back surface.

Furthermore, if the solder flows unnecessarily and adheres to the back side of the board, it looks bad, and there is also the problem that the product value decreases due to poor appearance.

[Purpose of the invention] The present invention was developed in view of the above circumstances, and it is possible to solder the back side edge of the board and the metal container with good workability and reliability, and to prevent the product from having poor appearance. The purpose is to provide a hybrid integrated circuit whose value does not decrease.

[Summary of the invention] The outline of the invention to achieve the above object is to form a circuit on the surface of a board, store this circuit in a metal container, and solder the back edge of the board to the metal container. By forming a frame-shaped heat-resistant film on the back surface of the substrate,
The present invention is characterized in that a solder margin is formed on the edge of the back surface of the substrate.

[Example of idea] Hereinafter, the present invention will be explained in detail through implementation.

FIG. 1 is a perspective view showing the appearance of a hybrid integrated circuit according to an embodiment of the present invention, and FIG. 2 is a plan view showing the back side of the substrate of the hybrid integrated circuit shown in FIG.

In FIGS. 1 and 2, 1 indicates fixing terminals 1a and 1 for mounting on a printed circuit board (not shown).
The metal container 2 is made of ceramic or metal, for example, and the substrates 5a and 5 have circuits formed on their surfaces (not shown).
b, 5c, 5d are lead lines from the circuit, 6
7 is a hole for adjusting the circuit, and 7 is solder for fixing the board 2 to the metal container.

On the back surface of the substrate 2, there are lead lines 5a, 5.
A ground electrode 2a is formed except around the areas b, 5c, and 5d, and this ground electrode 2a is electrically connected to the metal container 1 via solder 7.

Further, 3 denotes a heat-resistant film, such as a resist, formed in a frame shape on the back surface of the substrate 2, and the resist 3 forms a solder margin 8 on the edge of the back surface of the substrate 2.

In addition, a resist 4 is also provided in a frame shape around the adjustment hole 6.
is formed.

In this way, by forming a solder margin using the resist 3 on the back surface of the board 2, when the board 2 is fixed to the metal container 1, the melted solder will not flow out beyond the resist 3 to the outside of the solder margin 8. , product value does not decrease due to poor appearance. Moreover, for the same reason, the melted solder rises within the solder allowance 8, so that the back edge of the substrate 2 and the metal container can be easily and reliably soldered.

The reason why the resist 3 is formed in a frame shape and not over the entire back surface of the substrate 2 is as follows. If the circuit formed on the surface of the substrate 2 is not yet housed in the metal container 1, the grounding (grounding electrode) of the circuit will naturally be necessary for applying voltage, etc., for example when adjusting the circuit. This is because if the circuit is formed over the entire area of the board 2 except for the solder area 8, the circuit cannot be grounded unless the circuit is housed in the metal container 1.

Further, the adjustment hole 6 may be filled with solder, but even in such a case, the resist 4 formed around the adjustment hole 6 can block the solder, so melted solder can be easily removed. The adjustment hole 6 can be reliably filled with the necessary minimum amount of solder.

Therefore, the hybrid integrated circuit according to this embodiment allows easy soldering between the back edge of the board and the metal container.
Moreover, it can be carried out reliably, and the product value will not be reduced due to poor appearance.

One embodiment of the present invention has been described above, but
The present invention is not limited to the above embodiments,
It goes without saying that modifications can be made as appropriate within the scope of the gist of the present invention.

For example, in the above embodiment, the heat-resistant film is a resist, but any film that can withstand the temperature of melted solder may be used, and for example, a film made of glass may be used.

[Effects of the invention] As explained above, according to the invention, it is possible to solder the back edge of the board and the metal container with good workability and reliability, and the product value is reduced due to poor appearance. Therefore, it is possible to provide a hybrid integrated circuit without any problem.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the external appearance of a hybrid integrated circuit according to an embodiment of the present invention, and FIG. 2 is a plan view showing the back side of the substrate of the hybrid integrated circuit shown in FIG. 1...Metal container, 2...Substrate, 3...Resist (heat-resistant film), 8...Solder cost.

Claims (1)

[Scope of utility model registration request] In a hybrid integrated circuit in which a circuit is formed on the surface of a substrate, this circuit is housed in a metal container, and the edge of the back surface of the substrate is soldered to the metal container, a heat-resistant film is formed in the shape of a frame on the back surface of the substrate. A hybrid integrated circuit characterized in that a solder margin is formed on the edge of the back surface of the substrate.