JP3375283B2 - Semiconductor device and circuit module including the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device handling a relatively high DC voltage, and more particularly to a structure capable of ensuring electrical insulation between its terminals.

[0002]

2. Description of the Related Art For example, a traveling wave tube mounted on an artificial satellite
(TWT) As a rectifier used for a driving power source, a semiconductor device in which a plurality of high voltage diodes connected in series are connected to four bridges is general. This semiconductor device is several kV
Despite handling the above DC high voltage, it is strongly demanded to be small and lightweight.

Therefore, in the conventional semiconductor device as shown in FIG. 4, four high-voltage diodes D1 to D4 are arranged at the respective apexes of a substantially regular quadrangle so as to be parallel to each other and are connected to the internal lead wires. External lead terminals 2A to 2D before being connected to the bridge and covered with the outer enclosure 1.
Are mechanically entangled in the connection parts and fixed with solder S. Thereafter, they are molded with an outer envelope 1 such as an electrically insulating resin, and the external lead terminals 2A, 2B, 2C, 2D are formed on a pair of short side surfaces 1X of the outer envelope 1 facing each other.
Are derived respectively. As shown in FIG. 5, each lead-out external lead terminal was bent to the printed board 3 side, cut into an appropriate length, and attached through a through hole (not shown) of the printed board 3 by soldering.

The external lead terminals 2A and 2B are DC output terminals, and the external lead terminals 2C and 2D are AC input terminals. From the internal structure, the outer lead terminals 2A and 2B are led out from the outer enclosure 1 at substantially the same height, and the outer lead terminals 2C and 2D have different heights, but the outer lead terminals 2C and 2D are not displaced in the left-right direction. 1 and is bent outside the envelope 1 as shown in FIG.

Further, not only the semiconductor device but also the circuit module mounting the semiconductor device is required to have very high reliability. Therefore, after the semiconductor device as described above is mounted on the printed circuit board 3 of the circuit module, In order to prevent all of the external lead terminals 2A to 2D of the semiconductor device from being exposed, a portion of at least the highest position of the external lead terminal 2 from the root of the external lead terminal 2 to a surface of the printed circuit board 3 is molded with an electrically insulating resin 4 with a specific resin or the like. Often. Although not shown, the external lead terminals 2 on the printed circuit board 3 are also shown.
The soldering parts 5 of A to 2D are also molded with the same resin 6 as the electrically insulating resin 4 so as not to be exposed to the air.

[0006]

However, the one having such a structure has a part of the external lead terminals 2A to 2D, for example, 2C.
However, there is a problem that the amount of the molding resin is large and the semiconductor module is not lightened as a circuit module even if the semiconductor device is made smaller and lighter.

Further, since the lower surface of the outer enclosure 1 of the semiconductor device is brought into contact with the printed board 3 and resin-molded,
A large number of voids remain between the lower surface of the envelope 1 and the surface of the printed circuit board 3, and the external lead terminals 2A and 2B
There was also a problem that the dielectric strength between and was reduced.

Further, as the size of the semiconductor device is reduced and the distance between the external lead terminals becomes narrower, if the external lead terminals are directly inserted into the through holes of the printed circuit board 3, the external lead terminals on the surface of the printed circuit board 3 are separated. However, there was a problem that the creepage distance was shortened, causing an increase in leak current and electrical breakdown.

[0009]

In order to solve the above-mentioned problems, in the first invention, a plurality of external lead terminals are formed from the same exposed surface of the envelope formed by sealing one or more semiconductor elements. In the semiconductor device derived from, the protrusions for increasing the creepage distance between the external lead terminals are formed between the external lead terminals, and the protrusions are formed on the same exposed surface more than the protrusions. A semiconductor device having a tall stopper portion is provided.

In order to solve the above problems, the second
According to another aspect of the invention, in a semiconductor device in which a plurality of external lead terminals are led out from the same exposed surface of an enclosure that seals one or more semiconductor elements, a plurality of high voltage diodes are arranged so as to be parallel to each other at substantially equal intervals. To form a full-wave rectifier circuit, connect external lead terminals to the positive electrode, negative electrode, and AC electrode of the full-wave rectifier circuit, bend these external lead terminals in one direction, and surround the bent portion. Surrounded by the body,
There is provided a semiconductor device characterized in that a protrusion is provided on the outer surface of the outer body from which the external lead terminal is led out, and a stopper that is taller than the protrusion is provided.

In order to solve the above problems, the third
According to another aspect of the present invention, in a circuit module including the semiconductor device according to claim 1 or 2, the external lead terminals of the semiconductor device are inserted and soldered between the through holes, and the printing between the through holes having a narrow gap between the through holes. Provided is a circuit module characterized in that a narrow slit is provided on a substrate to increase a creepage distance between the through holes.

In order to solve the above problems, the fourth
According to another aspect of the present invention, in the circuit module including the semiconductor device according to claim 1 or 2, the distance between the through hole into which the external lead terminal of the semiconductor device is inserted and soldered is the root of the external lead terminal. A circuit module is provided in which the external lead terminals are widened and are inserted into the through-holes.

[0013]

Embodiments and Examples of the Invention An embodiment of a semiconductor device according to the present invention will be described with reference to FIGS. In these figures, the same symbols as those used in FIGS. 4 and 5 indicate corresponding members.

As can be seen from FIG. 1, this semiconductor device has the same arrangement and connection structure of the diodes D1 to D4 as the conventional one, but after the external lead terminals 2A, 2B, 2C and 2D are soldered with solder S, The structure is such that it is bent in one direction, and the bent portion is covered with the outer envelope 1. Briefly, as shown in FIG. 2D, a glass-wave type diode D1 to D4 formed by laminating and adhering a plurality of diode pellets is connected in a four-bridge structure to form a full-wave rectifier circuit. , An external lead terminal 2A connected to the positive electrode 2a, an external lead terminal 2B connected to the negative electrode 2b, and external lead terminals 2C and 2D connected to the AC electrodes 2c and 2d, respectively. These external lead terminals are led out substantially vertically from the bottom surface of the outer envelope 1.

Between the external lead terminals 2A and 2B, 2C and 2
Between D, the external lead terminal 2A is used due to the restriction of size and weight reduction.
It is narrower between 2C and 2C than between 2B and 2D, and there is concern about electrical insulation. Therefore, the external lead terminal 2
In order to increase the creepage distance between A and 2B and between 2C and 2D to secure the electrical insulation distance, the protrusions 1A, 1
B was formed. Further, a stopper portion 1C having a short cylindrical shape is formed at the center of the bottom surface of the outer envelope 1. This is higher than the height of the protrusions 1A and 1B for increasing the creepage distance, and
When mounted on the printed circuit board 3, the projections 1A and 1B for increasing the creepage distance serve as a stopper function so as not to contact the printed circuit board 3. Protrusions 1A and 1B and stopper 1
The difference in height from C is that the protrusions 1A and 1B and the printed circuit board 3
A space may be provided between and so that the mold resin easily flows.

Further, in this embodiment, when the external lead terminals 2A to 2D are inserted into the through holes of the printed board 3 and soldered, the creepage distances between the external lead terminals 2A and 2B and between the external lead terminals 2C and 2D on the printed board 3 are measured. Is shortened and there is concern about electrical insulation. Therefore, the printed circuit board 3 corresponding to between the external lead terminals 2A and 2B and between 2C and 2D is used.
A slit 3A, which is a long and narrow through hole, is formed in the.

FIG. 2 shows an example in which this semiconductor device is mounted on the printed circuit board 3. As can be seen from this figure, the stopper portion 1C abuts on the surface of the printed board 3, and a gap is formed between the surface of the printed board 3 and the projections 1A and 1B for increasing the creepage distance. External lead terminal 2A ~
When the lower part of the semiconductor device and the surface of the printed circuit board 3 are molded with the electrically insulating resin 4 so that the 2D is not exposed, the surface of the printed circuit board 3 and the protrusions 1A, 1
Since the electrically insulating resin 4 easily enters into the gap between B and B, a void unlike the conventional case is not formed between them. Therefore, desired electrical insulation can be obtained between the external lead terminals 2A and 2B and between the external lead terminals 2C and 2D.

In the above embodiments, the protrusions 1A and 1B for increasing the creepage distance are linear, but the ring-shaped protrusions respectively surrounding the external lead terminals 2A to 2D, or the external lead terminals such as wavy ones. The shape is not particularly limited as long as it is a structure that increases the creepage between them.

Similarly, the stopper portion 1C that also performs the stopper function, unless the creepage distance between the external lead terminals is reduced, is set on the bottom surface of the outer envelope 1, the size, the number,
The shape and the like are not limited, and it is of course possible to provide a plurality of pieces having the same height.

The slits of the printed circuit board 3 are not always necessary, and the through hole intervals of the printed circuit board 3 are formed to be wide enough to ensure desired electrical insulation, and the intervals of the external lead terminals 2A to 2D are expanded to form the through holes. Of course you can insert it. Further, although the rectifying diode is described in the embodiments, the present invention can be similarly applied to a semiconductor device that handles a relatively high voltage of several kV or more.

[0021]

As described above, according to the present invention, the electrical insulation distance between the external lead terminals can be sufficiently secured even when the semiconductor device handling a relatively high voltage is downsized, and the external lead terminals are not exposed. Even when the external lead terminal and the printed circuit board to which the external lead terminal is mounted are molded with resin or the like as described above, voids are not formed between the projection of the outer casing of the semiconductor device and the printed circuit board, so that electrical insulation can be ensured.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a semiconductor device of the present invention.

FIG. 2 is a diagram showing a semiconductor device according to an example of the invention.

FIG. 3 is a diagram showing a circuit module according to an embodiment of the present invention.

FIG. 4 is a diagram showing a conventional semiconductor device.

FIG. 5 is a diagram showing a conventional circuit module.

[Explanation of symbols]

1 ... Enclosure of semiconductor device 1A, 1B ... Protrusions formed on the bottom surface of the semiconductor device 1C ... Stopper 2 External lead terminal 3 ... Printed circuit board 4, 6 ... Contact prevention sheet 5 ... Solder D1-D4 ... Diode

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-50-79268 (JP, A) JP-A-54-159867 (JP, A) JP-A-63-18653 (JP, A) JP-A-5- 235501 (JP, A) JP-A-8-97333 (JP, A) JP-A-6-45478 (JP, A) Actual opening Sho 59-173372 (JP, U) Actual opening Sho 62-140744 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 23/28 H01L 25/04 H01L 25/18 H05K 1/18

Claims (4)

(57) [Claims] 1. In a semiconductor device in which a plurality of external lead terminals are led out from the same exposed surface of an envelope formed by encapsulating one or more semiconductor elements, a creeping distance between the external lead terminals is increased. The semiconductor device is characterized in that the protrusion is formed between the external lead terminals, and a stopper portion that is taller than the protrusion is provided on the same exposed surface on which the protrusion is formed. 2. In a semiconductor device in which a plurality of external lead terminals are led out from the same exposed surface of an enclosure that seals one or more semiconductor elements, a plurality of high voltages are arranged so as to be parallel to each other at substantially equal intervals. A diode is arranged to form a full-wave rectifier circuit, the positive electrode, the negative electrode, and the AC electrode of the full-wave rectifier circuit are connected to external lead terminals, respectively, and these external lead terminals are bent in one direction, and the bent portion is outside. A semiconductor device which is surrounded by an enclosure and is provided with a protruding portion on the outer surface of the outer enclosure from which the external lead terminals are led out, and a stopper portion which is taller than the protruding portion. 3. A circuit module comprising the semiconductor device according to claim 1 or 2, wherein an external lead terminal of the semiconductor device is inserted and soldered, and a through hole having a narrow gap between the through holes. A circuit module characterized in that a narrow slit is provided on a printed circuit board between the holes to increase a creepage distance between the through holes. 4. A circuit module comprising the semiconductor device according to claim 1 or 2, wherein an external lead terminal of the semiconductor device is inserted and soldered, and the distance between the through holes is the above. A circuit module characterized in that the external lead terminals are wider than the roots and are inserted into the through holes by expanding these external lead terminals.