JPH0631732Y2 - Hybrid integrated circuit for surface mounting - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical field to which the invention belongs) The present invention relates to a hybrid integrated circuit (hybrid IC), and
The present invention relates to a hybrid integrated circuit having a terminal electrode structure suitable for automatic surface mounting and a resin mold outer shape.

(Prior art and its problems) In a hybrid integrated circuit, film circuits such as conductors and resistors are formed on an insulating substrate such as ceramic or resin, and small chip parts such as semiconductor devices, capacitors, and inductors are mounted on the hybrid integrated circuit, It is a circuit block having various electrical functions whose surface is molded with resin. Generally, such a hybrid integrated circuit has a large number of external dimensions and a small amount of individual production. Moreover, it is economically difficult to adopt a transfer mold or a casting mold that requires a dedicated mold corresponding to each external dimension, so it is usually difficult to mold a hybrid integrated circuit. Methods such as liquid dip molding and powder fluidized immersion molding that do not require a mold are used. However, many of the hybrid integrated circuits formed by such a molding method do not have a flat surface due to unevenness according to the shape of the internally mounted components.

Most of the conventional hybrid integrated circuits have many lead pins and are mounted by inserting them into the holes of the printed circuit board (printed wiring board) to which they are mounted. Since most of the methods are used, there is a large variation in external dimensions, and it is difficult to automatically insert a large number of lead pins without any trouble because the reference for positioning in the insertion hole at the time of insertion cannot be determined.

In recent years, due to the progress of automatic component mounting technology, surface mounting technology (SMT = Surface Mount Tech) has been adopted for mounting components on a printed circuit board.
has been widely applied, an automatic component mounting machine for mass production has been put into practical use, and it is popular because it is easier and more efficient to mount than the lead insertion mounting method for components with leads.
So-called chip-type small electronic components suitable for this surface mounting technology have been put into practical use.

The conditions that such a chip-type component for automatic mounting by SMT should have are that a plurality of electrodes are arranged on the same plane, and the component land portion of the printed wiring on the other printed circuit board to be mounted is contacted by this electrode. It is a so-called leadless structure that is integrated, and the transfer of the mounted parts from the preparation box to the other party's printed circuit board when mounting with an automatic machine is usually performed by vacuum suction, so the top surface of the part is flat There are two points. However, due to the above situation, there is no ordinary hybrid integrated circuit suitable for automatic surface mounting that satisfies these two conditions.

(Object of the Invention) An object of the present invention is to provide an electrode structure suitable for automatic mounting on a printed circuit board to solve such a difficulty, and a surface-mounting hybrid integrated circuit having a shape having a flat portion on the upper surface of a mold. Especially.

(Structure of the Invention) The hybrid integrated circuit for surface mounting of the present invention is a rectangular circuit board on which film circuits such as wiring conductors and resistors and small chip parts are mounted on one side or both sides, and a plurality of sides of the circuit board. A plurality of metal terminal electrodes provided on the edge of the circuit board for electrically and mechanically connecting the circuit of the circuit board and the circuit of the external printed circuit board, the film circuit mounted on the circuit board, and the small chip component. In a hybrid integrated circuit including a molding resin formed so as to be encapsulated, the plurality of metal terminal electrodes have a U-shaped cross-section at a connection portion on one side of the circuit board, It is sandwiched and fixed by soldering to the electrode lands on one side or both sides of the circuit board, and the connection part with the external printed board at the other end is from the lower left end of the U-shape of the connection part on the circuit board side to the bottom surface of the circuit board. Folded along or Then, bend downward at a right angle, and further bend at a right angle with a space so that the backside components mounted on the circuit board do not contact the external printed circuit board, and then electrically and mechanically connect to the external printed circuit board on the same plane. The mold resin is characterized in that the center portion of the upper surface thereof has a flat portion substantially parallel to the circuit board.

Hereinafter, the details of the present invention will be described with reference to the drawings.

1 is a perspective view showing the outer shape of an embodiment of a hybrid integrated circuit according to the present invention, and FIG. 2 is a vertical sectional view of the hybrid integrated circuit of FIG. In FIG. 1 and FIG. 2, reference numeral 1 is a circuit board in which a film circuit such as a conductor wiring and a resistor is formed on one side or both sides of a rectangular insulating substrate such as ceramic or resin. The film circuit such as the conductor wiring and the resistor may be provided on one surface only on the same surface as the component mounting surface, or on both surfaces provided on the surface opposite to the component mounting surface like the film circuit 5.
Reference numeral 2 is a small chip electronic component such as a semiconductor device or a capacitor mounted on the circuit board 1. 3 is fitted in the peripheral portion of the circuit board 1 (for example, two opposite sides or four sides),
A plurality of U-shaped metal terminal electrodes electrically and mechanically connected to the electrode lands of the circuit board 1 by solder or the like. The electrodes 3 serve as terminals for surface connection on the same plane when solder reflow bonding is performed after automatic mounting on the external printed circuit board on which the hybrid integrated circuit is mounted, and at the same time, the circuit board 1 is a double-sided wiring board as described above. In this case, it also serves to connect the wiring patterns on both sides to each other. The portion of the U-shaped metal terminal electrode 3 in contact with the external printed circuit board may be projected outward from the edge of the circuit board 1 by d or may be d = 0. This is effective when a visual soldering inspection is performed after surface connection and soldering. Reference numeral 4 is a resin mold applied to the surface on which the chip component 2 is mounted, and has a flat surface 11 at the center of the upper surface, which is suitable for handling by suction during automatic mounting.

FIG. 3 is a plan view showing an embodiment of the hybrid integrated circuit according to the present invention. As shown in these plan views (a), (b), (c), and (d), the present invention is applied to a square, rectangular, or other square-shaped hybrid integrated circuit. The terminal electrodes 3 are provided on four sides in the case of (a), three sides in the case of (b), and two opposite sides in the cases of (c) and (d).

FIG. 4 is a vertical cross-sectional view of another embodiment of the hybrid integrated circuit according to the present invention mounted on an external printed board. In this embodiment, small chip components 2 and 20 are mounted on both sides of a circuit board 1, and a resin mold 4 is applied to both of them.
In this case, when the plurality of U-shaped metal terminal electrodes 30 are surface-connected to the printed wiring lands 21 of the external printed circuit board 20,
The resin mold 4 on the surface on which the small chip component 20 is mounted is kept at a distance g so as not to contact the printed circuit board 20.

FIG. 5 is a perspective view for explaining the operation when the hybrid integrated circuit 6 according to the present invention described above is automatically surface-mounted on the external printed circuit board 20. The hybrid integrated circuit 6 according to the present invention placed in a storage box called a magazine (not shown)
At point C, one flat surface 11 is sucked and lifted by a vacuum suction nozzle 22 provided at the tip of an arm 23 of the automatic surface mounter. The arm 23 moves from the point C to the point D around the axis 24.
Rotate to point and the hybrid integrated circuit 6 is transferred to point D. Point D is a position where the terminal electrode 3 of the hybrid integrated circuit 6 matches the printed wiring land portion 21 of the external printed circuit board 20 on which the hybrid integrated circuit 6 is mounted, and the arm 23 vertically descends to release the vacuum suction. Thus, the hybrid integrated circuit 6 is mounted at a desired position. The mounting position of the hybrid integrated circuit 6 on the external printed circuit board 20 is, for example, as shown in FIG.
It is only necessary to set m to a desired dimension with the corners of M as the positioning reference, and the dimensional tolerance of m is automatically determined by automatically inserting the lead pins of the conventional hybrid integrated circuit having a large number of lead pins into the holes provided on the printed circuit board. The margin can be set larger than the deviation when inserting.

It is obvious that the above-described operation is easy to be performed accurately, quickly, and repeatedly by an automatic machine which actually makes use of a highly developed microcomputer, and has a great effect on mass production.

Next, the U-shaped metal terminal electrode 3 which is a feature of the present invention,
A resin mold having a flat portion on the upper surface will be described.

FIG. 7 shows a circuit board 1 in which a U-shaped metal terminal electrode 3 is formed.
It is a perspective view showing a method of attaching to. By fitting the so-called lead frame 15 in which the lead pins 12 are connected by the tie bars 13 to the land 14 for the terminal electrode on the peripheral portion of the circuit board 1, fixing with solder, and cutting the lead pins 12 at the portion BB indicated by the alternate long and short dash line The electrodes 3 arranged at a constant pitch can be easily provided on the periphery of the circuit board 1.

FIG. 8 is a perspective view in the case of forming the U-shaped metal terminal electrode 30 in the embodiment of FIG. By using the lead frame 16 shown in FIG. 8 and cutting the leads along the dotted line BB, it is possible to obtain an electrode structure in which a gap g is secured on the lower surface of the circuit board 1. Can be implemented.

Next, a hybrid integrated circuit having a flat portion on the upper surface was previously proposed (Japanese Patent Application No. 62-185397), and FIG. 6 shows the central portion of the upper surface of the mold resin 4 of the hybrid integrated circuit according to the present invention. It is sectional drawing which showed an example of the method of forming a flat part.

In FIG. 6, 8 to 10 indicate molding jigs. 8 is a jig base, 9 is a spacer, and 10 is a holding plate.
A semi-finished product in the molding process of the hybrid integrated circuit according to the present invention is shown between the holding plate 10 and the holding plate 10. In the case of actual production, a large number of hybrid integrated circuits are mounted on one set of molding jigs 8 to 10. However, only one hybrid integrated circuit is shown for the sake of clarity. .

Reference numeral 7 denotes a predetermined appropriate amount of paste-like thermosetting resin applied from above the component mounting surface of the hybrid integrated circuit before molding. A plurality of spacers 9 are arranged around the jig base 8 and have a height equal to the finished thickness of the hybrid integrated circuit, and a flat holding plate 10 substantially equal to the area of the jig base 8 thereon. Are fixed in parallel with the jig base 8. A resin release agent is applied to the pressing plate 10 in advance so that it will not stick to the pressing plate 10 when the paste thermosetting resin 7 is cured by heating. Further, the shape and the number of the spacers 9 are determined in consideration of keeping the holding plate 10 in parallel with the jig base 8 in a stable manner. The amount of the paste thermosetting resin 7 applied is determined such that when the jigs 8 to 10 are loaded, a part of the upper surface is flattened by the pressing plate 10 as shown in the figure. As shown in the figure, the composite integrated circuits loaded in the jigs 8 to 10 are heated together with the jigs, and after the resin 7 is sufficiently cured, the holding plate 10
Get rid of. Since the release plate 10 is coated with a release agent in advance, it can be easily removed without resin sticking,
A molded finished product of the hybrid integrated circuit can be obtained.

Mixed integrated circuits have different shapes and many floor areas because the type and number of small electronic components are different according to various functional circuits.However, if the mold jigs as described above are used, the same applies to different types. The jig 9 can be used, and the height of the spacer 9 only needs to be selected in order to cope with the difference in the thickness of the hybrid integrated circuit due to the height of the mounted components.

Also, the area of the flat top surface of the hybrid integrated circuit provided for automatic mounting has a margin for the suction area at the tip of the suction cup required for vacuum suction, and it is practical if it is located in the approximate center of the hybrid integrated circuit. It's enough.

(Effects of the Invention) As described in detail above, the hybrid integrated circuit having the electrode structure and the mold shape according to the present invention facilitates automatic surface mounting on the printed circuit board, dramatically improving the mounting efficiency, and at the same time the printed circuit board. By mounting the hybrid integrated circuit of the present invention on the printed circuit board, the entire printed circuit board can be miniaturized with high density and its economic effect is great. The fact that the hybrid integrated circuit becomes one of the components for automatic surface mounting on the printed circuit board has a great influence on the conventional printed circuit board mounting technology, and its industrial ripple effect is extremely large.

[Brief description of drawings]

1 is a perspective view showing an embodiment of the hybrid integrated circuit according to the present invention, FIG. 2 is a vertical sectional view of the hybrid integrated circuit of FIG. 1, FIG. 3 is a plan view showing an embodiment of the present invention, and FIG. FIG. 5 is a vertical cross-sectional view showing another embodiment of the hybrid integrated circuit according to the present invention mounted on an external printed board, FIG. 5 is a perspective view for explaining the operation of automatic surface mounting, and FIG. 6 is a mold jig. FIG. 7 is a longitudinal sectional view showing the structure of the present invention, FIG. 7 is a perspective view showing the structure of the U-shaped metal terminal electrode portion of the present invention, and FIG. 8 is the structure of the electrode portion in the case of the embodiment of FIG. FIG. DESCRIPTION OF SYMBOLS 1 ... Circuit board, 2 ... Chip parts, 3,30 ... U-shaped metal terminal electrode, 4 ... Mold resin, 5 ... Membrane wiring conductor, 6 ... Hybrid integrated circuit by this invention, 7 ... … Paste-like mold resin, 8 …… Jig base, 9 …… Spacer, 10
…… Presser plate, 11 …… Top flat surface, 12 …… Lead pin, 13
...... Tie bar, 14 ...... land, 15,16 ...... lead frame, 20 …… external printed circuit board, 21 …… printed wiring land, 22 …… vacuum suction nozzle, 23 …… arm, 24 …… axis.

Claims (1)

[Scope of utility model registration request] 1. A rectangular circuit board on which a film circuit such as a wiring conductor and a resistor and a small chip component are mounted on one side or both sides, and a circuit of the circuit board provided at edges of a plurality of sides of the circuit board. And a plurality of metal terminal electrodes for electrically and mechanically connecting the circuit of the external printed circuit board, and a mold resin formed so as to enclose the membrane circuit and the small chip component mounted on the circuit board. In the hybrid integrated circuit including: a plurality of metal terminal electrodes, a connecting portion on one side of the circuit board has a U-shaped cross section, and electrodes on one side or both sides of the circuit board sandwiching an edge portion of the circuit board. Soldered and fixed to the land for connection, the other end of the connection portion with the external printed circuit board is bent along the bottom surface of the circuit board from the lower left end of the U-shape of the connection portion on the circuit board side, or further continuously downward. Bend at a right angle to the circuit board Is formed to be electrically and mechanically surface-connected to the external printed circuit board on the same plane by further bending the component on the back surface mounted on the external printed circuit board at a distance so as not to contact the external printed circuit board. The surface mount hybrid integrated circuit, wherein the molding resin is formed such that a central portion of an upper surface thereof has a flat portion substantially parallel to the circuit board.