JPH01274499A - Electronic part - Google Patents

Abstract

PURPOSE:To inhibit the fluctuation of supply voltage generated at the time of the switching of an output while reducing noises leaking from each of lead terminals by laminating a magnetic substance film continuing in the direction of juxtaposition of said lead terminals onto all the lead terminals in a package through an insulating film. CONSTITUTION:Beltlike magnetic substance films 30a, 30b continuing so as to respectively cross in the direction of juxtaposition of lead terminals are laminated onto the lead terminals 12a to 12d, 12e to 12h at every four through beltlike insulating films 20a, 20b. Since inductance L equivalent to the case when an inductance element is mounted in the presence of the magnetic substance films 30a, 30b as magnetic substances is generated while the magnetic substance films 30a, 30b have conductivity, electrostatic capacitance C1 to C4, C5 to C8 are generated among lead terminals and the magnetic substance films 30a, 30b by the laminated structure of respective lead terminal, the insulating films 20a, 20b and the magnetic substance films 30a, 30b, thus constituting a low-pass filter. Accordingly, unnecessary high-frequency voltage generated in an IC chip 11 can be absorbed by the inside of an IC 10, thus inhibiting the leakage of noises to the outside of the IC 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electronic component having a large number of lead terminals.

[Conventional technology]

Conventionally, in a semiconductor integrated circuit (hereinafter referred to as IC), when it is a digital circuit such as TTL, the output of its many lead terminals varies from 'HJ' to 'LJ'.
Or vice versa, an excessive current momentarily flows through the lead terminal for TiB, but if the impedance of the power supply is high as seen from the IC, the power supply voltage of this IC itself or the power supply voltage on which it is mounted Not only can the power supply voltage of other electronic components on the printed circuit board temporarily drop, causing malfunction, but also pulses may cause the lead terminals of the IC and the wiring pattern on the printed circuit board to which they are connected. As a result, electric current flows and electromagnetic fields are radiated into the surrounding space, which may cause interference with other electronic components and communication equipment.

As a countermeasure against this, normally a bypass capacitor 3 is interposed between the DIP type ICI as an electronic component and the printed circuit board 2, and a A mounting method is used in which a bypass is created between the lead terminal 4a and the grounding lead terminal 4b.

[Problem to be solved by the invention]

However, the conventional example described above had the following disadvantages.

The mounting method using the bypass capacitor 3 acts to lower the impedance of the power supply seen from the IC, so it prevents the voltage aN voltage from fluctuating due to transient currents that occur when the output signal is switched, for example, and prevents ICI malfunction. Although this method is effective in preventing noise, it is insufficient in terms of reducing noise leaking from both sides of the lead terminals. Moreover, it is necessary to use a dedicated bypass capacitor 3 that matches the shape of the ICI, and it is pointed out that the mounting volume increases and the time and effort during mounting increases, leading to higher costs.

The present invention was made in view of these circumstances, and has a simple configuration that does not use additional parts such as conventional bypass capacitors, and has a simple configuration that does not use additional parts such as conventional bypass capacitors. The purpose of this is to suppress fluctuations in the voltage and to reduce noise leaking from the lead terminal sides as much as possible.

[Means to solve the problem]

In order to achieve the above object, the present invention has the following configuration.

That is, the electronic component according to the present invention has a large number of lead terminals, and a magnetic material that is continuous in the direction in which the lead terminals are arranged in parallel is provided on all the lead terminals in the package through an insulating film. It is characterized by the fact that the membranes are stacked.

[Effect]

The effects of this configuration are as follows.

The presence of the magnetic film produces an effect equivalent to that of providing an inductance element between the lead terminals located on both sides, and the laminated structure of each lead terminal, insulating film, and magnetic film reduces the distance between each lead terminal and the magnetic film. Since a capacitance is generated in the electronic component, a low-pass filter is constructed inside the electronic component.

As a result, unnecessary high-frequency voltages generated inside the electronic component are absorbed, noise leaks from the sides of the lead terminal to the outside of the electronic component, and the space around the lead terminal and the pattern wiring of the printed circuit board to which it is connected is reduced. This will also prevent electromagnetic field radiation.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

A first embodiment of the present invention is shown in FIGS. 1 to 3, where FIG. 1 is a plan view of an electronic component, and FIG. 2 is a -
3 is an equivalent circuit diagram around the lead terminal of the IC shown in FIG. 1. Here, a DIP type IC will be described as an example of an electronic component.

In the turned ICl0, 11 is an IC chip, 123~
12h is a lead terminal bent into an L shape, 13 is a molded resin as a package for these (dotted chain line in the figure)
It shows. The lead terminals 12a to 12h are divided into four terminals each on two side surfaces 13a and 13b of the molded resin 13, and are provided so as to protrude parallel to each other. These lead terminals +2 a to 12 d,
One end of each of 12 e to 12 h is connected to a corresponding bonding pad (not shown) of the ICC chip 1 with a bonding wire 14 .

And four lead terminals 12a to 12d,
On 12e to 12h, there is a continuous strip-shaped magnetic film 30a spanning the lead terminals in the direction in which they are arranged.

30b are laminated with strip-shaped insulating films 2Qa and 20b interposed therebetween. The insulating films 20a and 20b may be made of, for example, S
iOx+Sio, Al1tOs, etc. are preferable, and the magnetic films 30a, 30b include, for example, Ni.
, Fe.

Ni-Fe alloy, AA-Fe alloy, Aj! -Fe-5i
e alloy or Co-Nb-B alloy, Fe-N1-P-
Amorphous alloys such as B alloys are preferred, and these are formed by a film forming method such as vacuum evaporation or spatter. Note that the insulating films 20a and 20b may be made of polyimide, silicone rubber, etc., and the magnetic materials 1'1130a and 30b may be made of Fe, Cu, A
j! , Cu-Zn alloy, etc. may also be used.

By the way, the lead terminals 12a = 12d, 12e ~ 1 on the two sides 13a, 13b of the molded resin 13
The equivalent circuit according to the 2h12e configuration is shown in FIG.
12h), a magnetic film 30a (
30b) produces an inductance L equivalent to that in the case where an inductance element is provided, and since the magnetic film 30a (30b) is conductive, each lead terminal.

Insulating film 20a (20b) and magnetic material 1*30
Product of a (30b) Due to NJJ construction, there is a capacitance fi between each lead terminal and the magnetic material m30a (30b).
cl 5-C4 (cs to C6) will result, thus forming a low-pass filter.

Since such a low-pass filter can be configured, unnecessary high-frequency voltages generated on the IC chip 11 can be reduced by rct.
o It is possible to absorb the noise internally, and it is possible to suppress the noise from leaking to the outside of ICl0.

Therefore, ICl0's 'it source voltage voltage fluctuates.
It is possible to prevent malfunctions of the ICl0 itself and its surrounding circuits, and it is also possible to reduce interference to other circuits.6 As in this embodiment, the noise generated from the ICl0 itself is internally absorbed. When configured to do so, not only does it not require the use of a conventional bypass capacitor, but also the noise leaking to the outside can be reduced compared to the conventional method, and the noise entering from outside the IC can also be reduced.

[Another example]

The fourth example concerns the second embodiment of the present invention, and shows a sectional view corresponding to FIG. 2. In this embodiment, as shown in the figure, insulating films 20a to 20d and magnetic films 30a to 30a are disposed above and below the lead terminals 12a to 12d, 12e to 12h on both sides 13a and 13b of the molded resin 13.
30d increases the inductance and capacitance compared to the first embodiment.

This configuration improves the ability of the low-pass filter and
Noise leaking from inside Cl0 to the outside can be further reduced.

Further, FIG. 5 shows a cross-sectional view corresponding to FIG. 2 according to a third embodiment of the present invention. In this embodiment, lead terminals 12a to 12h are connected to insulating films 20a to 20d, respectively.
upper and lower magnetic films 30a to 3 with the lead terminal in between.
0d are connected between the lead terminals. According to this configuration, it is possible to further reduce noise leaking to the outside from between the lead terminals, and it is also possible to more effectively reduce noise entering from the outside.

In each of the above embodiments, it is also possible to provide external lead-out terminals for the magnetic films 308 to 30d on the IC 10 and connect this to a low impedance point on the printed circuit board, and in this case, the effect is even greater. demonstrate. Alternatively, the magnetic films 30a to 30d may be connected to the lead terminal with the lowest impedance.

Further, in the above embodiment, a DIP type IC is described as an electronic component, but the present invention is not limited to this, and can be applied to any device that has a large number of lead terminals on the outside of the package. Needless to say.

〔Effect of the invention〕

In the present invention, the presence of the magnetic film produces an effect equivalent to that of providing an inductance element between the lead terminals located on both sides, and the laminated structure of each lead terminal, the edge film, and the magnetic film allows each lead terminal to Since a low-pass filter is constructed inside the electronic component by creating capacitance between it and the magnetic film, unnecessary high-frequency voltages generated from inside the electronic component can be absorbed, thereby preventing noise from leaking to the outside of the electronic component. It is also possible to reduce electromagnetic field radiation to the space around the lead terminal and the pattern wiring of the printed circuit board to which it is connected.

Therefore, it is possible to prevent malfunctions of the electronic component and other electronic components provided around the electronic component due to fluctuations in the power supply voltage of the electronic component, and to reduce interference to other circuits.

In this way, the present invention provides a noise absorption function inside the electronic component, so compared to the conventional method using bypass capacitors, the mounting volume does not needlessly increase, and the mounting effort is reduced. It can contribute to cost reduction and has excellent practical effects.

[Brief explanation of the drawing]

FIGS. 1 to 3 relate to one embodiment of the present invention;
2 is a plan view of the electronic component, FIG. 2 is a cross-sectional view taken along the line ■--■ in FIG. 1, and FIG. 3 is an equivalent circuit diagram around the lead terminal of the IC shown in FIG. 1. FIGS. 4 and 5 relate to other embodiments of the present invention,
Both figures correspond to FIG. 2. FIG. 6 is a perspective view showing a mounting form of an electronic component using a conventional bypass capacitor. 10...IC (electronic component) 122-12h...Lead terminal 14...Mold resin (package) 20a-20d
... Insulating films 303 to 30d... Magnetic film.

Claims (1)

[Claims] (1) In an electronic component having a large number of lead terminals, a magnetic film is laminated on all the lead terminals in the package with an insulating film interposed therebetween in a direction in which the lead terminals are arranged in parallel. Featured electronic components.