JPH0447971Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a method for fixing external terminals in a hybrid circuit formed by connecting a substrate on which an arbitrary circuit is configured in addition to an integrated circuit.

[Prior art and its problems]

In the current situation where most electronic circuits are integrated circuits, there are some circuits that include inductance, such as delay line circuits made up of a combination of coils and capacitors, which are difficult to integrate. If such a circuit is included, it must be connected to the outside of the integrated circuit. Such an example also corresponds to the case where a buffered delay line is constructed by combining a delay line with a saturation type logic circuit using TTL elements.

Then, configure a delay line circuit by arranging coils and capacitors on the board, stacking it on the flat package of the integrated circuit, connecting both circuits via the terminals of the flat package, and connecting the external terminals to the dual in-line package ( A hybrid circuit exposed to the outside of a DIP (hereinafter referred to as a DIP) is known from Japanese Utility Model Application Laid-Open No. 58-89953.

However, in the conventional hybrid circuit, as shown in the explanatory diagram of Fig. 5, the flat package 4, the board 3, the coil 1 and the capacitor 2 that constitute the delay line are stacked one on top of the other in the same direction. DIP
It is difficult to reduce the thickness T. So board 3
The external terminals 5 and the terminals 6 of the flat package 4 are connected near the sides of the board 3 by separating them from the sides so as not to surround the circuit elements inside the board 3, thereby reducing the planar area of the board 3. It is conceivable to arrange the circuit elements on the same side as the flat package 4 by widening them. In that case, if the connections between the board 3 and various terminals are not symmetrical in plan with respect to the wide surface of the board 3, and are made in offset positions, the force of the resin flowing into the mold during resin sealing may cause This tends to cause the board 3 to tilt or the connected parts to come apart.

〔the purpose〕

The purpose of the present invention is to fix the tips of external terminals to the four corners of the board so that the board can be supported on two-dimensionally symmetrical sides when encapsulated in resin, thereby preventing hybrid circuits that occur when thinning the board. It is about solving technical problems.

[Technical means to solve problems]

In the present invention, a board on which a circuit including a coil is configured and a flat package of an integrated circuit having a narrower planar area than the board are superimposed, and both circuits are connected through terminals of the flat package. It is a hybrid circuit that is entirely sealed in resin with the external terminals connected to either circuit exposed.
The terminal is characterized in that the tips of the external terminals located at the terminals are fixed to at least the four corners of the board.

〔Example〕

Taking the circuit diagram of the buffered delay line shown in FIG. 4 as an example, an explanation will be given below with reference to FIGS. 1 and 3 showing an embodiment of the hybrid circuit of the present invention.

In Figure 4, 10 is a TTL element, 11 is an input terminal, 12 is a ground terminal, 13 to 17 are output terminals, 18 is a power supply terminal, 19 is a coil, 20
is a capacitor, and 21 is a resistor. and six
The TTL element 10 is constructed in a flat package 30 of the integrated circuit shown in FIGS.

The substrate 31 has holes 32 and 34 penetrating its surface.
A groove 33 is provided on one side. Further, recesses 43 are provided at the four corners. In the hole 34 and the groove 33, a terminal 3 is bent from the bottom side to the top side of the flat package 30, which has a narrower planar area than the board 31.
5, the substrate 31 and flat package 30 are overlapped. The hole 32 is for fitting the coil 19, and is made into a circular shape having approximately the same size as the flange of the drum core in consideration of the case where the coil 19 wound around the drum core is installed upright. The hole 32 is located at a position where the substrate 31 and the flat package 30 do not overlap, and the coil 19 fitted into the hole 32 from below is located at the side of the flat package 30 as shown in FIG.
The coil 19 is fixed from the upper side of the substrate 31 to the adhesive surface of an adhesive tape 41 that closes the bottom of the hole 32. Note that the board 31 in FIG. 2 is illustrated with circuit elements corresponding to the dotted lines in FIG. For this reason, the conductor patterns formed around the holes 34 and grooves 33 are not shown.

The flat package 30 is of a 14-pin type with seven terminals exposed on each side of the opposite side, except for the terminal 35 which is bent upward for connection to the circuit on the board 31. 36
is bent along its outer surface and extends to the outer surface 42 on the opposite side from the substrate 31. The terminals 36 are then connected to external terminals 37A through 37H, respectively, on the outer surface 42. There are two types of shapes for the tip of the external terminal that connects to the terminal 36: one that is split into two and one that is elongated. The tip 38, which is split into two, holds the terminal 36 between its outer surfaces 42 as shown in FIG. 3a, and the elongated tip 39 is soldered along with the terminal 36 as shown in FIG. to obtain soldering reliability. The elongated shape of the tip 39 serves to prevent short-circuit accidents at the tip when connecting to adjacent terminals 36 such as the external terminals 37A and 37B.

Among the eight external terminals, the external terminals 37A, 37D, 37E, and 37H located at the ends are provided with bent portions 44 that bend vertically upward, and the bent portions 44 are inserted into the recessed portions 43 of the substrate 31. It is fitted and fixed. Although not shown, an independent conductor pattern not connected to the circuit conductor pattern is provided around the recess 43, and the bent portion 44 is soldered to the conductor pattern. In other words, the tip of the external terminal located at the end is connected to the flat package 3.
In addition to the connecting portions with the terminals 36 of 0, bent portions 44, which are other tips, are fixed to the four corners of the substrate 31. Note that the horizontal portions of the external terminals 37B and 37C are bent into a crank shape, but this is to make the intervals between all the external terminals equal.

The upwardly bent terminals 35 of the flat package 30 are soldered to the conductor pattern around the holes 34 and grooves 33. The six terminals 35 are connected to the output side terminal of the TTL element 10 connected to the five output terminals 13 to 17 in FIG. 4, and to the output side terminal of the TTL element 10 connected to the input terminal 11, respectively. handle. The eight terminals 36 bent downward correspond to the output terminals 13 to 17, the input terminal 11, the power supply terminal 18, and the ground terminal 12, respectively. Then, the whole is sealed with resin as shown by the dashed line in FIG. 1, and the internal circuit is drawn out to the outside of the DIP by an external terminal connected to the terminal 36.

The external terminals 37A to 37H are bent along the outer surface of the DIP and extend to the bottom surface 40, so that they can be directly connected to the conductor pattern when attached to another circuit board with other circuit components. . In the embodiment, the recesses 43 at the four corners of the substrate 31 facilitate the positioning of the tips of the external terminals located at the ends, but they may not exist. Further, the fixing position may be near the four corners. Furthermore, the tips of the external terminals are all connected to the terminals 36 of the flat package 30, but some of the external terminals, including the external terminals at the ends, are connected to the sides of the board 31 to connect the internal circuit. It is also possible to change the design so that it can be pulled out. Furthermore, some of the external terminals whose tips are fixed at the four corners may be fixed only at the four corners.

〔effect〕

As described above, the hybrid circuit of the present invention is constructed by overlapping a flat package and a board, and the tips of the external terminals located at the terminals are fixed to at least the four corners of the board. In order to make the hybrid circuit thinner, the four corners of the board can be firmly supported by external terminals when resin sealing is performed, even if the connections of various terminals are asymmetrical and offset to the surface of the board. be done. Therefore, the board may tilt due to the force of the resin,
There is no possibility of defective products due to disconnection of the connected parts.

[Brief explanation of the drawing]

Fig. 1 is an explanatory assembly diagram showing an embodiment of the hybrid circuit of the present invention, Fig. 2 is an exploded perspective view, and Figs. 3a and 3b are plan views showing the connection portion between the external terminal and the terminal of the flat package. 4 are circuit diagrams of a buffered delay line, and FIG. 5 is an explanatory diagram of a conventional hybrid circuit. 30... Flat package, 31... Board,
32, 34... hole, 33... groove, 35, 36...
Terminals, 37A to 37H...External terminals, 38, 39
... Tip, 40 ... Bottom, 43 ... Recess, 44 ...
...bending part.

Claims (1)

[Scope of utility model registration request] A board on which a circuit including a coil is configured and a flat package of an integrated circuit, which has a narrower planar area than the board, are stacked on top of each other.Both circuits are connected through the terminals of the flat package, and either It is a hybrid circuit that is entirely sealed with resin with the external terminals connected to the circuit exposed, and is characterized by the tips of the external terminals located at the ends being fixed to at least the four corners of the board. hybrid circuit.