JPH09121093A - Shield laminated electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain high shielding effect by placing a GND electrode, whose trimming is possible, on the front and rear of the top lamination surface, and making a vertical direction against the lamination surface a mounting direction, and making a surface facing the mounting surface the GND electrode. SOLUTION: An electrode paste is so printed on a dielectric substance or an insulation substance, made into a sheet in a doctor blade method, etc., as to be a specified form in a screen printing method, and the dielectric substance or insulation substance sheet and the electrode paste laminate the printed dielectric substance or insulation substance sheet. Then, after cut into specified size, as GND electrodes 1 and 9, the things, on which the electrode paste is so printed on the external surface parallel to the lamination surface and on the external surface vertical to the lamination surface as to be a specified form, are burned. Then, a signal electrode is coated with the electrode paste by rubber transferring, etc., for printing. At this time, a trimming surface is made on the side surface, so that change of center frequency due to an external cause is suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield type laminated electronic component which is not easily influenced by the outside.

[0002]

2. Description of the Related Art A mobile communication device typified by a mobile phone is destined to be small and lightweight due to the nature of the set. As a matter of course, the circuit board built in it requires high-density mounting, and the component interval is controlled on the order of 0.1 mm. Particularly in the thickness direction of the circuit board, the set chassis or another circuit board is arranged, so that electromagnetic interference between components is likely to occur. Therefore, it is necessary for the components used in mobile communication devices to have shielding properties.

In a conventional shield type electronic component, when GND electrodes are arranged above and below the outermost part of the laminated surface and mounted,
The GND electrode and the substrate are mounted so as to be parallel to each other (described in JP-A-2-108321). Further, in these shield-type electronic components, the external GND electrode is usually trimmed to adjust the internal element value.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of a shield type electronic component that trims the electrodes, a situation in which the shield type electronic component is used because the internal element is exposed from the trimmed portion, for example, a circuit mounted in a bandpass filter in a mobile phone. When a metal chassis is placed in parallel with and close to the board, conventional shielded electronic components (bandpass filter) produce distributed capacitance between the electromagnetically exposed internal elements and the metal chassis by trimming. However, the center frequency characteristic of the bandpass filter is adversely affected.

Therefore, the present invention provides a shield type electronic component which is not affected by a metal chassis or the like arranged in parallel and close to such a circuit board.

[0006]

[Means for Solving the Problems] Trimmable GND electrodes are arranged above and below the outermost part of a stacking surface, the mounting direction is perpendicular to the stacking surface, and the surface facing the mounting surface is the GND electrode. As a result, an extremely high shielding effect is possible.

[0007]

EXAMPLES The present invention will be described in more detail below by showing specific examples of the present invention.

FIG. 1 shows a circuit of a typical LC bandpass filter, and FIG. 2 shows its attenuation-frequency characteristic. The center frequency f _{0, which} is important for the characteristics, is determined by the two resonant circuits of the coil L ₁ and the capacitors C ₃ and L ₂ and C ₄ , and is desired by trimming C ₃ and C ₄ for commercialization. Has the characteristics of.

3 (a) and 3 (b) are structural views of the shield type electronic component of the present invention and the related art. 1,9,10,1
8 is a GND electrode. The coils L ₁ and L ₂ shown in FIG.
Are formed in 2 and 11 patterns. Further, in each capacitor, C ₁ is between 3-4 and 12-13, and C ₂ , C
₅ is between 4-5 and 13-14, and C ₃ and C ₄ are 5-
6, 6-7, 7-9 and 14-15, 15-16,
It consists of 16-18. External views of these shield-type electronic components are shown in FIGS. 4 and 5. Here, the adjustment of the center frequency f ₀ shown in FIG.
Is done by trimming. Therefore, if a metal shield or the like is added to the trimming portion from the outside or if radiation noise is present, the center frequency f ₀ of the LC filter characteristic changes.

These chips were prepared by the following method.
The dielectric or insulating sheet made into a sheet by the doctor blade method or the like is shown in FIGS. 3 (a) and (b) 2-7, 11-16.
The electrode paste is printed by a screen printing method so as to have a predetermined shape as shown in, and the dielectric or insulating sheet and the dielectric or insulating sheet on which the electrode paste is printed are laminated. After cutting into a predetermined size, GND
As electrodes, 1,9,1 on the outer surface parallel to the stacking plane
The electrode paste was printed so as to have a predetermined shape as shown in FIGS. As a matter of course, after that, the signal electrode was coated with an electrode paste by rubber transfer or the like and baked. Here, the sheet construction method has been described, but it goes without saying that it can also be manufactured by the printing construction method.

6 and 7 show the mounting states of the present invention and the conventional shield type electronic component. In the conventional example, the trimming surface is the upper surface in the mounted state. In high-density packaging in recent years, it is essential to place another substrate above the substrate on which the LC filter is mounted. At this time, radiation noise may be received from above and the metal case (shield) of other components may approach. It is inevitable to do. In the conventional example, since the trimming surface is arranged above, a change in the center frequency cannot be avoided although it depends on the trimming amount.

On the other hand, according to the present invention of FIG. 6, since the trimming surface is arranged on the side surface, it is possible to suppress the change of the center frequency due to the external factor.

Table 1 shows characteristic changes of the center frequency f ₀ when the ground electrode (metal piece) is arranged with a gap of 0.05 mm and 0.1 mm provided on the mounting upper surface of the present invention and the conventional example.

[0014]

[Table 1]

Normally, the permissible value of the fluctuation of the center frequency f ₀ required for the bandpass filter is ± 0.5%, but the center frequency f ₀ is already ± 0.5% due to manufacturing precision. It fluctuates in the range. That is, further fluctuation of the center frequency f ₀ due to the influence of external parts or the like is a problem because the mobile communication device set may be out of the standard.

Here, the measurement was carried out by the circuit and apparatus as shown in FIGS. In addition, the measurement method is as follows. The sample 22 is soldered to the measurement substrate 21 shown in FIG. 9, the grounded metal piece 23 is brought close to the sample so as to form a predetermined gap, and the measurement device 20 (HP-8720C network analyzer) is used. It was measured.

As can be seen from Table 1, in the conventional bandpass filter, the fluctuation value Δf ₀ / f ₀ of the center frequency fluctuates due to the presence of the ground electrode. However, the bandpass filter according to the present invention has the ground electrode. Although it exists, it has hardly changed. Here, when the gap of the ground electrode becomes 0.05 mm, the bandpass filter according to the present invention also fluctuates by a small amount of -0.1 (%). However, it is usually sufficient to consider the distance to external parts up to about 0.1 mm, and in practice, the gap is 0.05 mm.
Even if such a gap occurs, a remarkable difference is clearly seen from the conventional example. Therefore, it is understood that the laminated electronic component according to the present invention has a higher shielding effect than the conventional one.

[0018]

As described above, according to the present invention,
By arranging GND electrodes that can be trimmed above and below the outermost surface of the laminated surface of the shield-type electronic component, with the mounting direction perpendicular to the laminated surface, and by using the GND electrode on the mounting upper surface, a very high shielding effect can be obtained. Can be realized.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a typical LC bandpass filter.

FIG. 2 Attenuation amount frequency characteristic of a typical LC bandpass filter

FIG. 3A is a structural diagram of a shield-type laminated electronic component according to the present invention. FIG. 3B is a structural diagram of a conventional shield-type laminated electronic component.

FIG. 4 is an outline drawing of a finished product of a shielded laminated electronic component according to the present invention.

[FIG. 5] Outline drawing of a finished product of a conventional shielded laminated electronic component

FIG. 6 is a mounting state diagram of a shielded laminated electronic component according to the present invention.

FIG. 7 is a mounting state diagram of a conventional shielded laminated electronic component.

FIG. 8 is a diagram showing a measurement circuit.

FIG. 9 is a diagram showing a measuring device.

[Explanation of symbols]

1,9,10,18 GND electrode 2 Coil electrode 3,4,5,6,7,12,13,14,15,16 Capacitor electrode 8,17 Dielectric 11 Coil electrode 19 Solder 20 Measuring instrument 21 Measuring board 22 Sample 23 Metal piece C1, C2, C3, C4, C5 Capacitor L1, L2 Coil

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location H01G 4/40 H01G 4/34 H03H 7/075 4/40 321A

Claims (1)

[Claims] 1. A GND electrode is arranged on an outer surface, a signal electrode is arranged so as to be mounted in a direction perpendicular to a laminated surface, and a GND electrode on an outer surface parallel to the laminated surface is trimmed. Shield type multi-layer electronic component.