JP2002118424A - Surface mounting piezoelectric oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a piezoelectric oscillator comprising a piezoelectric oscillator and a chip-like circuit component constituting an oscillation circuit mounted on a surface mounting printed board in which the occupation area of the entire piezoelectric oscillator is prevented from increasing or is decreased by eliminating the need for enlarging the area of the printed board even if the number of components to be mounted on the printed board is increased. SOLUTION: In the piezoelectric oscillator comprising a piezoelectric oscillator 23 and a circuit component 24 constituting an oscillation circuit mounted on a surface mounting printed board 21, one chip component is mounted on a wiring pattern 50 on the surface mounting printed board when at least two chip components being connected in parallel are present in the circuit components and the other chip component is mounted on one chip component and then respective chip components are secured while connecting the electrodes thereof in parallel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a surface-mount type piezoelectric oscillator, and more particularly to a surface-mount type piezoelectric oscillator having a piezoelectric oscillator having a piezoelectric vibrating element and a circuit component constituting an oscillation circuit, which is simplified and reduced in size. Type piezoelectric oscillator.

[0002]

2. Description of the Related Art With the rapid progress of cost reduction and miniaturization accompanying the spread of mobile communication devices such as mobile phones, piezoelectric oscillators such as crystal oscillators used as frequency control devices in these communication devices have been developed. However, there is an increasing demand for cost reduction, size reduction, and thickness reduction. In response to such demands, in addition to the crystal oscillator, an oscillator circuit including a frequency adjustment circuit, a frequency temperature compensation circuit, etc., is integrated, and IC components are mounted on a single surface mount printed circuit board. And make it more compact. FIG. 7 is a longitudinal sectional view showing a schematic configuration of a conventional surface-mount type piezoelectric oscillator, and is shown on a wiring pattern 2 on a surface-mounting printed circuit board (hereinafter referred to as a printed circuit board) 1 made of an insulating material such as glass epoxy. The packaged quartz resonator 3 and the circuit component 4 as a chip component are mounted, and the upper surface of the printed circuit board including the components is surrounded by a lid 5. This type of piezoelectric oscillator has various components 3, 4 on the upper surface of a printed circuit board 1.
Are mounted in parallel, the occupied area of the individual components 3 and 4 and the total occupied area including the clearance between the components increase as the number of components increases. As a result, the area of the printed circuit board 2 and the entire piezoelectric oscillator Occupies a large area.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has an oscillator circuit including a piezoelectric vibrator, a frequency adjusting circuit, a frequency temperature compensating circuit, and the like on a surface mount printed circuit board. Even if the number of components to be mounted on a printed circuit board increases in a piezoelectric oscillator mounted with chip-shaped circuit components, the area occupied by the piezoelectric oscillator is prevented from increasing by eliminating the need to increase the area of the printed circuit board Or a surface mount type piezoelectric oscillator capable of reducing the occupied area.

[0004]

In order to solve the above problems, a first aspect of the present invention is a surface mount type piezoelectric oscillator having a piezoelectric vibrator and a circuit component constituting an oscillation circuit mounted on a surface mount printed circuit board. In the above, when there are at least two chip components connected in parallel in the circuit components,
One chip component was mounted on a wiring pattern on the surface mounting printed board, the other chip component was placed on the upper surface of the one chip component, and the electrodes of each chip component were connected in parallel and fixed. It is characterized by the following. According to a second aspect of the present invention, there is provided a surface-mount type piezoelectric oscillator in which a piezoelectric vibrator and a circuit component constituting an oscillation circuit are mounted on a surface-mount printed circuit board, wherein a recess is formed on an upper surface of the surface-mounted print board. A chip component is fitted in the recess, another chip component is placed on the upper surface of the chip component, electrodes of both chip components are connected in parallel and fixed, and a printed circuit board corresponding to the periphery of the recess The wiring pattern formed above is electrically connected to an electrode of at least one of the chip components. According to a third aspect of the present invention, there is provided a surface mount type piezoelectric oscillator in which a piezoelectric vibrator and a circuit component forming an oscillation circuit are mounted on a surface mount printed board, wherein a recess is formed on an upper surface of the surface mount printed board. A chip component is fitted in the recess, another chip component is placed on the upper surface of the chip component, electrodes of both chip components are connected in parallel and fixed, and an electrode of the chip component is provided in the recess. A wiring pattern formed on a printed circuit board corresponding to the periphery of the recess is electrically connected to an electrode of the other chip component.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. FIG. 1 is a longitudinal sectional view of a surface mount type piezoelectric oscillator according to a first embodiment of the present invention.
This surface-mount type piezoelectric oscillator is, for example, a crystal oscillator 20, which is a crystal oscillator packaged on a wiring pattern 22 on a surface-mounting printed board (hereinafter, referred to as a printed board) 21 made of an insulating material such as glass epoxy. A vibrator 23 and a circuit component 24 as a chip component are mounted, the upper surface of the printed circuit board including the components 23 and 24 is surrounded by a lid 25, and the bottom of the lid 25 is fixed to the periphery of the printed circuit board. . In the crystal oscillator 20 of this embodiment, at least two chip components 24a, 24b, and 24c that are electrically connected in parallel to each other in the circuit component 24.
..., when there is, one chip component 24a is mounted on the wiring pattern 22 on the printed circuit board 21, and the other chip component 24b is placed on the one chip component,
The electrodes 26b of the chip components 24a and 24b are connected in parallel, and then fixed by a binder B such as solder or conductive adhesive. The chip component 24 has a configuration in which electrodes 26b are provided at both ends of a main body 26a having a hexahedral shape such as a rectangular parallelepiped, and the other chip component 24b is placed on the upper surface of one chip component 24a. Thus, the two electrodes 26b can be electrically connected to each other by the binder. It is to be noted that the mounting is not limited to the case where the electrodes are stacked in two layers vertically, but may be stacked in three or more layers. In any case, the electrodes of the chip components stacked in the vertical position are electrically parallel to each other. Only when connected. According to this embodiment, a plurality of chip components that are connected in parallel with each other are stacked vertically and mounted on a printed circuit board, so that the total occupied area of the chip components on the printed circuit board is Can be greatly reduced, the area of the printed circuit board can be reduced, and the number of components that can be mounted on the printed circuit board having a fixed area can be increased.

FIGS. 2 (a), 2 (b) and 2 (c) are views showing another example of the mounting structure of the chip component of FIG. 1. FIG. 2 shows the upper surface of the lower chip component 24a. 2 shows an example in which chip components 24b having a smaller plane area are stacked and mounted. In this case, as shown in (a) and (b), when the total length of the upper chip component 24b is such that both electrodes 26b can be in contact with both electrodes 25 of the lower chip component 24a at the same time. In
What is necessary is just to connect by the binder between each electrode. However, if the length of the upper chip component 24b is so short that the electrodes 26b of the upper chip component 24b cannot contact the electrodes 26b of the lower chip component 24a, as shown in FIG. A protruding portion 26A, which protrudes the inner edge of both electrodes 26b (or either one) of the component 24a, is formed so as to protrude from the upper surface of the main body 26a, and the upper short chip component 24b is formed.
The two electrodes 26b can be reliably connected to both electrodes of the lower chip component 24a.

FIG. 3 is a view showing another example of a mounting structure for chip components. Small chip components 30 are mounted on the upper surface of lower chip components 24a mounted horizontally on a printed circuit board 21, respectively. Are connected and fixed in a vertically placed state, thereby connecting and fixing the lower electrode 31a of each chip component 30 on both electrodes 6 of the chip component 24a, and further mounting another long chip on the upper electrode 31b of each chip component 30. The feature is that the component 24b is placed horizontally so that the two electrodes 26b are connected.

FIG. 4 is a longitudinal sectional view showing a configuration of a surface mount type piezoelectric oscillator according to another embodiment of the present invention. This piezoelectric oscillator is, for example, a crystal oscillator 40. By fitting a crystal oscillator 43 and a chip component 44 into a concave portion 42 formed on a surface mount type printed circuit board 41 made of glass epoxy or the like, individual components can be formed. While the mounting height is reduced, another chip component 45 is stacked and mounted on the upper surface of the chip component 43 embedded in the recess 42. That is, the outer shape of the chip component 43,
Recess 42 having a planar shape and depth corresponding to the height dimension
Are formed in advance on the printed circuit board 41, and the chip components 44 are fitted into the recesses 42, respectively. Since the chip component indicated by reference numeral 44c in the figure is mounted alone, the wiring pattern 50 located on the periphery of the recess 42, that is, the upper surface of the printed board 41, is fitted in the recess 42. The electrodes 45 of the chip component are electrically connected by a binder (not shown) such as solder or conductive adhesive. On the other hand, a first chip component 44a is fitted into the other recess 42, and a second chip component 44b is placed on the upper surface of the first chip component 44a.
Further, the recesses 4 are formed in a state where the electrodes 45 of the chip components 44a and 44b are electrically connected in parallel by a binder.
2, the wiring pattern 50 provided on the printed circuit board 41 and the electrode 45 of one of the upper and lower chip components are electrically connected by a binder. In the example shown in FIG. 4, both electrodes 45 of the lower chip component 44a are connected to the wiring pattern 50, but as shown in FIG. The pattern 50 may be connected.

[0009] In another configuration example shown in FIG.
Two wiring patterns 51 are arranged inside the recess 42, the lower chip component 44a is fitted in a horizontal state, and both electrodes 45 are connected to each wiring pattern 51, while the wiring on the surface of the printed circuit board is connected. Pattern 50 and upper chip component 44
b and both electrodes 45 are connected. Further, in another configuration example shown in FIG. 5C, two small chip components 55 are vertically arranged in the recess 42 having the wiring pattern 51 therein, and the lower electrode 56 is Each of them is connected and fixed to the wiring pattern 51. Further, a large chip component 60 is placed on the upper electrode 57 of each small chip component 55, and both electrodes 61 are connected to the upper electrode 57 of each small chip component 55. Further, the wiring pattern 50 on the periphery of the concave portion 42 is electrically connected to both electrodes 61 of the chip component 60 by a binder. In the embodiment shown in FIG. 4 or FIG. 5A, FIG. 5B, or FIG. 5C, each of the plurality of chip components electrically connected in parallel on the printed circuit board is provided on one of the printed circuit boards. While embedding in the recessed portion, another chip component is placed on the chip component to connect the electrodes, and furthermore, to electrically connect the electrode of each chip component and the wiring pattern on the printed circuit board side. Therefore, a large number of components can be mounted without increasing the plane area of the printed circuit board.In addition, since one component is fitted in the recess, the height of the component increases and the overall height of the oscillator does not increase. can do. Fig.5 (a) (b)
By connecting the upper chip component directly to the wiring pattern 50 on the printed circuit board by a binder as shown in FIG. 3C, the connection strength of the component is increased, and the possibility of component drop is eliminated. Further, even if the upper component is displaced and mounted on the component in the recess, the connection strength can be sufficiently maintained because it is firmly fixed on the wiring pattern 50 on the printed circuit board. In FIGS. 5B and 5C, the wiring pattern 51 is formed in the horizontal hole 42a provided in the inner wall of the concave portion 42. However, for example, the vertical sectional view of FIGS. As shown in the plan view, a half through-hole 65 is formed along the inner wall of the recess 42, and the chip component 44a embedded in the recess 42 by filling the half through-hole 65 with a binder B such as solder. 45 may be connected to the wiring pattern 50 on the printed circuit board. The half through-hole 65 is formed in the recess 4 formed in the printed circuit board 41.
Longitudinal recesses 65a respectively formed on the opposing inner walls in 2
And a conductor film 65b formed on the inner wall of the recess 65a, and has a depth that does not penetrate the printed board 41.
By using the half through-hole 65 in this way, electrical and mechanical connection between the chip component and the wiring pattern 50 can be ensured.

[0010]

As described above, according to the present invention, a piezoelectric vibrator, a frequency adjusting circuit,
In a piezoelectric oscillator mounted with a chip-shaped circuit component constituting an oscillation circuit including a frequency temperature compensation circuit, etc., a plurality of chip components constituting a parallel circuit are stacked on a printed circuit board in a vertical positional relationship and connected. Even if the number of components to be mounted on the printed circuit board increases, it is not necessary to increase the area of the printed circuit board, so that the occupation area of the entire piezoelectric oscillator can be prevented from increasing, or the occupation area can be reduced. In addition, a recess is formed on the printed circuit board to bury one chip component, another chip component is stacked on the upper surface of the chip component, electrodes are connected, and furthermore, conduction with the wiring pattern on the printed circuit board side is established. Since we secured
A large number of chip components can be mounted on a printed circuit board without increasing the mounting height.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a surface mount type piezoelectric oscillator according to a first embodiment of the present invention.

FIGS. 2A, 2B, and 2C are diagrams showing another example of the mounting structure of the chip component of FIG. 1;

FIG. 3 is a diagram showing another example of a mounting structure of a chip component.

FIG. 4 is a longitudinal sectional view showing a configuration of a surface mount type piezoelectric oscillator according to another embodiment of the present invention.

FIGS. 5A, 5B and 5C are cross-sectional views showing examples of assembling chip components in an oscillator according to another embodiment of the present invention.

FIGS. 6A and 6B are a longitudinal sectional view and a plan view of a recess showing a mounting structure of a chip component according to another embodiment.

FIG. 7 is a longitudinal sectional view showing a schematic configuration of a conventional surface mount type piezoelectric oscillator.

[Explanation of symbols]

Reference Signs List 20 crystal oscillator (surface mount type piezoelectric oscillator), 21 surface mount printed circuit board (printed circuit board), 22 wiring pattern, 23 crystal unit, 24 circuit component, 24a,
24b, 24c chip parts, 25 lid, 26a body, 26b electrode, 30 small chip parts, 31a
Lower electrode, 31b upper electrode, 41 printed circuit board, 4
2 recess, 43 chip component, 44, 44a, 44
b, 44c chip parts, 45 chip parts, 50, 5
1 wiring pattern, 60 chip parts, 61 electrodes.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomohiro Tamura 2-1-1 Kotani, Samukawa-cho, Koza-gun, Kanagawa Prefecture Inside Toyo Tsushinki Co., Ltd. (72) Inventor Kazuhiro 2-chome Kotani, Samukawa-cho, Koza-gun, Kanagawa No. 1-1 Toyo Telecommunications Co., Ltd. (72) Inventor Masayuki Sakai 2-1-1 Kotani, Samukawa-cho, Koza-gun, Kanagawa F-term in Toyo Telecommunications Co., Ltd. 5J079 AA04 BA43 BA44 HA06 HA09 KA05

Claims (3)

[Claims] 1. A surface-mounted piezoelectric oscillator having a piezoelectric vibrator and a circuit component constituting an oscillation circuit mounted on a surface-mounted printed circuit board, wherein at least two chip components connected in parallel are included in the circuit component. In some cases, one chip component is mounted on a wiring pattern on the surface mount printed circuit board, the other chip component is placed on the upper surface of the one chip component, and the electrodes of each chip component are connected in parallel. A surface mount type piezoelectric oscillator characterized by being fixed by being fixed. 2. A surface mount type piezoelectric oscillator having a piezoelectric vibrator and a circuit component constituting an oscillation circuit mounted on a surface mount printed board, wherein a concave portion is formed on an upper surface of the surface mount printed board. A chip component is fitted in the place, another chip component is placed on the upper surface of the chip component, electrodes of both chip components are connected in parallel and fixed, and on a printed circuit board corresponding to the periphery of the recess. A surface-mounted piezoelectric oscillator in which the formed wiring pattern is electrically connected to an electrode of at least one of the chip components. 3. A surface-mounted piezoelectric oscillator having a piezoelectric vibrator and a circuit component constituting an oscillation circuit mounted on a surface-mounted printed circuit board, wherein a concave portion is formed on the upper surface of the surface-mounted printed circuit board. A chip component is fitted in the place, another chip part is placed on the upper surface of the chip part, and electrodes of both chip parts are connected in parallel and fixed. A wiring pattern formed on a printed circuit board corresponding to a peripheral edge of the recess is electrically connected to an electrode of the another chip component.