JP2001332932A - Piezoelectric oscillator - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a low-cost piezoelectric oscillator that can be reduced in size and has good production efficiency. SOLUTION: The crystal oscillator includes an IC (circuit component) 4 having a plurality of lead terminals and formed by resin molding, and a chip-type crystal resonator 1. Grooves 10a, 10b, 10c, and 10d are formed on the long side surfaces of the crystal unit, and external lead-out electrodes 16, 17, 18, and 19 are formed in the grooves. Lead terminals 41, 43, 4 on circuit component 4
The chip-type quartz resonator is mounted between 6, 6 and 48, and is arranged so that the lead terminals 41, 43, 46 and 48 are accommodated in the grooves 10a, 10b, 10c and 10d, respectively. In this state, the two are electrically and mechanically joined by a conductive resin adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric oscillator used for a communication device such as a portable telephone or an electronic device.

[0002]

2. Description of the Related Art A piezoelectric oscillator generally has a structure in which a piezoelectric vibrator and an integrated circuit element including an amplifier are integrally housed, and further has a voltage control function in which a frequency control function is added to the piezoelectric oscillator. There is a control-type piezoelectric oscillator, a temperature-compensated piezoelectric oscillator to which a temperature compensation function is added, and the like.

[0003]

Heretofore, these quartz oscillators (piezoelectric oscillators), feedback amplifiers, and circuit elements constituting additional functions have been arranged in a plane on a single substrate. However, due to recent demands for miniaturization of electronic components, mounting on these substrates has been in a direction of higher density and more integration, and miniaturization of the crystal unit itself is also being studied. However, in the case of flat mounting, the mounting area is inevitably limited, and miniaturization of the crystal unit is also
If the miniaturization is excessive, the parallel capacitance value becomes small, and the frequency variable amount in the frequency control circuit becomes small.

In order to avoid such a problem, a configuration in which a piezoelectric vibrator and a circuit element are arranged on the front and back of a package substrate has been considered. Japanese Patent Application Laid-Open No. 8-204452 discloses a configuration in which a piezoelectric element and electronic components are arranged on the front and back of a substrate in a temperature compensated oscillator. The package used here has a configuration in which a concave portion is formed on each of the upper and lower portions, and a piezoelectric element and an electronic component are stored in each concave portion. Although such a package is made of ceramic, it is difficult to manufacture such a structure having concave portions on the upper and lower sides, and there has been a problem that cost is excessively high when practically effective manufacturing accuracy is required.

Further, as disclosed in Japanese Patent Application Laid-Open No. 10-70414, a package (a structure in which a ceramic package or a lead frame is resin-molded) for accommodating an integrated circuit element is prepared, and a quartz oscillator is mounted on the package. A mounted configuration is disclosed. In this configuration, the use of a hermetically sealed quartz oscillator has the advantage that the characteristics of the quartz oscillator are not adversely affected.

However, when a plurality of components are stacked, there is a problem that the positioning and fixing operations are troublesome and productivity is reduced. Particularly, in recent years, miniaturization of quartz oscillators (piezoelectric oscillators) has progressed, and the above-mentioned problems have become apparent.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has been made to meet the demands for miniaturization and good production efficiency.
It is an object of the present invention to obtain a low-cost piezoelectric oscillator.

[0008]

In the piezoelectric oscillator according to the present invention, a plurality of lead terminals are led out from the side surface of the molded resin body, and a part of the lead terminals is lowered to form an external connection terminal. A chip-type piezoelectric vibrator mounted on an upper surface of the circuit part, a piezoelectric vibrating plate is supported and housed in a ceramic package, and hermetically sealed with a metal lid. A plurality of grooves are formed on the side surface of the terminal, an external lead electrode is formed in the groove, and another part of the lead terminal is raised upward, and a part or all of the groove is housed in the groove. In this state, the metal lid is electrically and mechanically connected to the extraction electrode, and the metal lid is electrically connected to one of the extraction electrodes and grounded.

According to the present invention, a chip-type piezoelectric vibrator can be arranged between the lead terminals of a circuit component that has been raised upward, and the electrical machine can be mounted in a state in which the lead terminal of the circuit component is housed in the groove. As a result, the positioning of the chip-type piezoelectric vibrator is ensured. Further, since the metal cover of the chip-type piezoelectric vibrator is connected to the ground via a part of the lead terminal, noise can be cut off.

According to a second aspect of the present invention, in the piezoelectric oscillator having the above structure, a connecting portion of a lead terminal connected to the chip-type piezoelectric vibrator is partially divided, and a tongue which can be pressed and connected to the external lead-out electrode. A configuration in which a piece is formed may be employed.

According to the second aspect of the present invention, the chip-type piezoelectric vibrator mounted thereon can be easily positioned and fixed by the tongue formed on the lead terminal of the circuit component.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 to 3 taking a surface mount type crystal oscillator as an example. FIG. 1 is a side view showing the present embodiment, FIG. 2 is a plan view showing the present embodiment, FIG. 3 is a side view seen from the short side direction, and the internal structure is also indicated by dotted lines. .

The crystal oscillator includes an IC (circuit component) 4 having a plurality of lead terminals and formed by resin molding, and a chip-type crystal resonator 1.

The crystal unit 1 is a ceramic package 1
0, and the storage unit 1 formed in the ceramic package 10
A quartz vibrating plate (piezoelectric vibrating plate) 3 housed in a housing 5 and a metal lid 2 for hermetically sealing the quartz vibrating plate 3 are provided. The ceramic package 10 is made of ceramics such as alumina and has a rectangular parallelepiped shape with an opening at an upper portion. A first metal layer 11 formed in a circumferential shape is formed on an upper surface of a portion around the opening. The first metal layer 11 is formed by stacking tungsten and nickel using a metallization technique and a plating technique, respectively. Supporting electrodes 13 and 14 for electrically and mechanically joining the crystal vibrating plate 3 to be described later are formed in the accommodating portion 15, and these supporting electrodes are connected to each other through internal wiring using a well-known ceramic lamination technique. It is appropriately electrically connected to an external lead-out electrode described later.

Grooves 10a, 10b, 10c, and 10d are formed on the long side surfaces of the ceramic package, and external lead-out electrodes 16, 17, 18, and 19 are formed in the grooves. A part of these external lead-out electrodes is connected to the support electrode as described above, and the other part is connected as a ground terminal. Each groove is set wider than the width of a lead terminal described later.

The quartz vibrating plate 3 is a rectangular AT-cut quartz plate. Exciting electrodes (not shown) are formed on the front and back surfaces, and the supporting electrodes 13 and 14 are respectively attached to the supporting electrodes 13 and 14 by a conductive resin adhesive (not shown). An electrode is extended to one end to be connected. The metal cover 2 is made of a metal plate such as Kovar as a base material, and a second metal layer (not shown) made of nickel or the like is formed corresponding to the metal layer 11. Then, the ceramic package 10 and the metal lid 2 are welded in an inert gas atmosphere or a reduced pressure atmosphere. As a joining method, known seam welding, laser welding, ultrasonic welding, or the like can be used. The metal lid 2 is electrically connected to one of the external lead-out electrodes in a ceramic package, and is grounded. In the present embodiment, the external lead electrode 1
Reference numeral 7 has a ground function, and the metal lid is electrically connected to the external connection electrode 17 via the first metal layer and the second metal layer.

The circuit component 4 is a resin mold type IC in which an IC chip 5 mounted on a lead frame is covered with a resin. More specifically, lead terminals 40 to 4
4 extends to one side, and lead terminals 45 to 49 are dual in-line types extending to the other side, and an IC 5 is mounted on a central portion of the lead frame. And the IC
Each electrode pad (not shown) of the chip is connected to each lead terminal with a bonding wire W as appropriate. After that, IC
The element 5 and a part of the lead terminal are covered with a mold,
A circuit component (resin mold type IC) is obtained by resin injection molding. Thereafter, each lead terminal separated from the lead frame is bent as follows. The lead terminals 40, 42, 44, 45, 47, and 49 are made of a resin body 4a.
Is bent downward to form an external connection terminal.
The other lead terminals 41, 43, 46, and 48 are bent and formed so as to rise upward.

The lead terminal 4 on such a circuit component 4
The chip-type crystal resonator is mounted between 1, 43, 46, and 48. In mounting, the grooves 10a, 10b,
The lead terminals 41, 43, 46,
48 are arranged so as to be accommodated respectively. As a result, the lead terminals 41, 43, 46, and 48 come into proximity or contact with the lead-out electrodes formed in the grooves, and in this state, they are electrically and mechanically joined by the conductive resin adhesive. Needless to say, in this embodiment, these connections are wired so as to function as a crystal oscillator.

Another embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a side view showing the embodiment,
FIG. 5 is a partial perspective view of the lead terminal, and FIG. 6 is a side view as viewed from the short side direction. The internal structure is also indicated by dotted lines.
Although a surface-mounted crystal oscillator is also exemplified in this embodiment, the structure has a function for temperature compensation, and other circuit components are mounted on an IC (circuit component) in addition to the crystal resonator. This is the configuration. Note that the same components as those in the above embodiment will be described using the same reference numerals, and a description thereof will be partially omitted.

The circuit component 6 is a resin mold type IC in which an IC chip 5 mounted on a lead frame is covered with a resin. More specifically, lead terminals 60 to 6
5 is extended to one side, and lead terminals 66 to 71 (partially not shown) are of a dual in-line type extended to the other side, and an IC 5 is mounted at a central portion of a lead frame. And each electrode pad of the IC chip (not shown)
And the respective lead terminals are appropriately connected by bonding wires W. Thereafter, the IC element 5 and a part of the lead terminals are covered with a mold, and a circuit component (resin mold type IC) is obtained by injection molding of a resin. Thereafter, each lead terminal separated from the lead frame is bent as follows. Lead terminals 60, 62, 64, 66, 6
8, 70 (partially not shown) are bent below the resin body 6a to form external connection terminals. The remaining lead terminals 61, 63, 65, 67, 69, 71 (partially not shown) are bent and formed so as to rise upward.

The leading ends of the lead terminals 61, 63, 65, 67, 69, 71 raised upward are partially divided into tongue pieces 611, 631, 651, 671, 671.
691, 711 (partially not shown) are formed. Each of the tongue pieces is bent inward so as to be pressed and connected to the external lead-out electrode, that is, in the direction of pressing the quartz oscillator or the like. The configuration of the tongue is not limited to the configuration, and the tongue for pressing may be formed by a configuration such as partial division from above the lead terminal.

In this embodiment, a capacitor 8 constituting a part of the temperature compensation circuit is also mounted on the IC as another circuit component, and the external lead electrodes 81 and 82 (82 are (Not shown) are connected to the lead terminals 65 and 71. It is preferable that a groove is formed on the capacitor side and an external lead-out electrode is formed in the groove from the viewpoint of improving positioning and connection reliability.

The lead terminal 64 on such a circuit component 6
The chip-type crystal resonator is mounted between 1, 63, 67 and 69. In mounting, the grooves 10a, 10b,
The lead terminals 61, 63, 67,
69 are arranged so as to be respectively housed (partly not shown). As a result, the lead terminals 61, 63, 67, and 69 come into proximity or contact with the lead-out electrodes formed in the grooves, and in this state, they are electrically and mechanically joined by the conductive resin adhesive. As described above, each of the external lead electrodes 81 and 82 of the capacitor 8 is connected to the lead terminal 6.
5, 71 are connected. Of course, in this embodiment,
By these connections, wiring is connected so as to function as a crystal oscillator having a temperature compensation function.

[0024]

According to the present invention, the chip type piezoelectric vibrator can be arranged between the lead terminals of the circuit component, and the electrical and mechanical connection is performed in a state where the lead terminal of the circuit component is housed in the groove. Therefore, the positioning of the chip-type piezoelectric vibrator is ensured. Further, since the metal cover of the chip-type piezoelectric vibrator is connected to the ground via a part of the lead terminal, noise can be cut off. Therefore, it is possible to obtain a low-cost piezoelectric oscillator that can be reduced in size and has good production efficiency.

According to the second aspect of the present invention, the chip-type piezoelectric vibrator mounted thereon can be positioned and fixed by the tongue formed on the lead terminal of the circuit component. Therefore,
In addition to the above effects, the reliability of the connection between the circuit component and the chip-type piezoelectric vibrator is improved.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment.

FIG. 2 is a plan view showing the embodiment.

FIG. 3 is a side view showing the embodiment, viewed from a short side direction.

FIG. 4 is a side view showing another example of the present embodiment.

FIG. 5 is a partial perspective view of a lead terminal used in another example of the present embodiment.

FIG. 6 is a side view showing another example of the present embodiment, viewed from a short side direction.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 crystal oscillator (piezoelectric oscillator) 10 ceramic package 11 first metal layer 2 metal lid 3 crystal oscillator (piezoelectric oscillator) 4, 6 circuit component 40, 41, 42, 43, 44, 45, 46, 47 , 4
8,49,60,61,62,63,64,65,6
6,67,68,69,70,71 Lead terminal 5 IC chip

Claims (2)

[Claims] 1. A plurality of lead terminals electrically connected to a built-in circuit element are led out from a side surface of a molded resin body, and a part of the lead terminals is lowered to form an external connection terminal. A piezoelectric oscillator comprising: a circuit component; a chip-type piezoelectric vibrator mounted on an upper surface of the circuit component, a piezoelectric vibrating plate supported and housed in a ceramic package, and hermetically sealed with a metal lid; A plurality of grooves are formed on the side surface of the chip-type piezoelectric vibrator, an external lead electrode is formed in the groove, and another part of the lead terminal is raised upward.
A part or the whole is housed in the groove portion, and it is electrically and mechanically connected to the external extraction electrode, and the metal lid is electrically connected to one of the extraction electrodes, and is grounded. Piezoelectric oscillator. 2. A connection part of a lead terminal connected to the chip-type piezoelectric vibrator is partially divided, and a tongue piece capable of being pressed and connected to the external lead-out electrode is formed. The piezoelectric oscillator as described.