JP2010183398A - Piezoelectric oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric oscillator that receives a plurality of kinds of piezoelectric vibration elements in different sizes or different shapes while using a common package, and also is compatible with both a cantilever-supporting structure and a double-supporting structure, with respect to a piezoelectric oscillator having an IC component incorporated in the package of a piezoelectric vibrator. <P>SOLUTION: The piezoelectric oscillator includes an insulated substrate 4, a piezoelectric vibrator 2 and the IC component accommodated in an IC component receiving recess. The insulated substrate includes: two projecting element mounting pads 10 and 11 disposed separately along a width direction eccentrically to one edge; a first pillow member 15 provided with a projecting conductive pad in the center, eccentric to another edge, in the width direction; and a second pillow member 20 provided with a projecting conductive pad in the center in the width direction in the center in a length direction, wherein an IC component receiving recess 25 is provided between the first pillow member and the second pillow member. The piezoelectric vibrator 2 has a piezoelectric vibrating element 30 mounted on the element mounting pads. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a voltage-controlled crystal oscillator in which an IC component is incorporated in a package of a piezoelectric vibrator (
Regarding the improvement of piezoelectric oscillators such as VCXO), not only can multiple types of piezoelectric vibration elements of different sizes and shapes be accommodated using a common package, but also support both cantilevered and dual-supported structures. The present invention relates to a piezoelectric oscillator.

In the mobile communications market, an increasing number of manufacturers are promoting modularization of parts groups for each function, taking into account the mounting properties, maintenance and handling characteristics of various electrical components, and the commonality of parts between devices. . Further, along with modularization, there is a strong demand for downsizing and cost reduction.
In particular, there is an increasing tendency toward modularization of circuit components that have established functions and hardware configurations, such as a reference oscillation circuit, a PLL circuit, and a synthesizer circuit, and that require high stability and high performance. Furthermore, there is an advantage that a shield structure can be easily established by packaging these component groups as modules.
Examples of the surface mounting electronic component constructed by modularizing and packaging a plurality of related components include a piezoelectric vibrator, a piezoelectric oscillator, a SAW device, and the like.
Among these electronic components, the piezoelectric oscillator has a configuration in which an oscillation circuit component and a temperature compensation component are connected to the piezoelectric vibrator. To reduce the size of the piezoelectric oscillator, the piezoelectric oscillator oscillates. A type incorporating an IC component constituting a circuit and a temperature compensation circuit has been developed.
In particular, in a voltage controlled crystal oscillator (VCXO), various crystal resonator elements (piezoelectric resonator elements) of different sizes and shapes are selected according to differences in various characteristics such as a desired oscillation frequency and amplitude. While it is necessary to use it, it is inefficient to prepare (manufacture, store, manage) a package having a different size and configuration for each crystal resonator element of different size and shape,
It is also a cause of cost increase.

In order to cope with such a conventional defect, Patent Document 1 discloses a crystal oscillator in which an IC component that constitutes an oscillation circuit or the like together with a crystal resonator element is incorporated in a crystal resonator package.
There is disclosed a package that can be used in common even if the lengths of the quartz resonator elements are different.
However, in this conventional example, crystal vibrating elements having different longitudinal dimensions and width dimensions can be supported only by cantilevering, and are supported by a double-supported structure that is effective in securing impact resistance. A configuration for this is not disclosed. In addition, it is assumed that the strip-shaped quartz resonator element is cantilevered, and a configuration for supporting a circular or other quartz resonator element is not disclosed.
For this reason, when the crystal resonator element has a double-sided structure or supports a non-striped crystal resonator element, this package structure cannot be adopted, and another dedicated package needs to be manufactured, stored and managed. . For this reason, the types of packages are increasing, and manufacturing costs and management costs are increasing.

JP 2004-260512 A

The present invention has been made in view of the above, and in a piezoelectric oscillator in which an IC component is incorporated inside a package of a piezoelectric vibrator, a plurality of types of piezoelectric vibration elements having different sizes and shapes can be accommodated using a common package. In addition to this, it is an object of the present invention to provide a piezoelectric oscillator capable of supporting both a cantilever support and a both-support support structure.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1] Two projecting element mounting pads arranged separately along the width direction near one edge in the longitudinal direction, and a projecting and conductive pad at the center in the width direction near the other end in the longitudinal direction. A first pillow member provided; a second pillow member provided with a projection and a conductive pad at a central portion in the width direction of the substantially central portion in the longitudinal direction; the first pillow member and the second pillow member; An insulating substrate having an IC component receiving recess provided in between, an IC component mounting pad provided in the IC component receiving recess, a piezoelectric vibration element mounted on the element mounting pad, and the piezoelectric A piezoelectric oscillator comprising: a lid member for hermetically sealing a vibration element; and an IC component having an electrode electrically connected to the IC component mounting pad and constituting an oscillation circuit.

In addition to the element mounting pads provided in the package, the first and second pillow members provided with the conductive pads are arranged, so that the size difference, strip shape (rectangle), circular shape, oval shape, elliptical shape, etc. It is possible to provide a piezoelectric oscillator having a common package structure capable of supporting not only the cantilever of the piezoelectric vibration element but also the support of both ends regardless of the difference in shape.

Application Example 2 A piezoelectric oscillator in which at least a part of one of the two element mounting pads is located at a central portion in the width direction near one end in the longitudinal direction of the insulating substrate.

One element mounting pad extends to the center of the insulating substrate in the width direction, so that the center of one edge can be adhered and held as required when supporting both ends of a piezoelectric vibration element. It becomes.

Application Example 3 The height H1 of the element mounting pad, the height H2 of the first pillow member, and the height H3 of the second pillow member are in a relationship of H1> H3 <H2. A featured piezoelectric oscillator.

Since the height of the second pillow member located substantially at the center in the longitudinal direction of the insulating substrate is configured to be low, interference with the piezoelectric vibration element can be prevented.

(A) is a longitudinal cross-sectional view of a voltage controlled crystal oscillator (VCXO) as an example of the piezoelectric oscillator of the present invention, (b) is a plan view showing a configuration in a package in which a crystal resonator element is mounted, c) is a plan view showing an in-package configuration in which a crystal resonator element is not mounted. (A) And (b) is a longitudinal cross-sectional view of the piezoelectric oscillator which concerns on other embodiment of this invention, and a top view which shows the structure in a package. (A) And (b) is a longitudinal cross-sectional view of the piezoelectric oscillator which concerns on other embodiment of this invention, and a top view which shows the structure in a package. (A) And (b) is a longitudinal cross-sectional view of the piezoelectric oscillator which concerns on other embodiment of this invention, and a top view which shows the structure in a package. (A) And (b) is the longitudinal cross-sectional view which shows the example of an assembly | attachment at the time of supporting both the circular quartz-crystal vibrating elements 30D, and the top view which shows the inside of a package.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
FIG. 1A is a longitudinal sectional view of a voltage controlled crystal oscillator (VCXO) as an example of a piezoelectric oscillator of the present invention, and FIG. 1B is a plan view showing a configuration in a package on which a crystal resonator element is mounted. (C) is a top view which shows the structure in a package which does not mount the crystal vibration element.
A crystal oscillator (piezoelectric oscillator) 1 includes a surface mount package 3 and a crystal resonator (piezoelectric resonator) 2 composed of a crystal resonator element (piezoelectric resonator element) 30 housed in the package 3.
And an IC component 40 accommodated in the package 3 of the crystal unit 2.
The package 3 includes an insulating substrate 4 and a lid member 50 that hermetically seals the recess on the insulating substrate 4.
The insulating substrate 4 is formed by laminating insulating sheets such as ceramic sheets, and is formed by a bottom plate 4a having a mounting terminal 5 at the bottom, an outer wall 4b erected from the periphery of the bottom plate, an upper surface of the bottom plate 4a, and an outer wall 4b. And the protrusion 6 disposed separately along the width direction (B) near the one end edge (left end edge) in the longitudinal direction (A) of the inner bottom surface (the upper surface of the bottom plate 4a) of the recess 6 Two element mounting pads 10, 11, a first pillow member 15 having a projection and a conductive pad 16 disposed in the central portion in the width direction on the upper surface near the other end in the longitudinal direction, and a substantially central portion in the longitudinal direction An IC component disposed between the first pillow member 15 and the second pillow member 20, which has a protruding shape and is provided with a conductive pad 21 disposed in the center in the width direction of the upper surface. A housing recess 25.

The electrodes of the IC component 40 are electrically and mechanically connected to the IC component mounting pad 26 provided in the IC component receiving recess 25 by soldering or the like. The IC component 40 constitutes an oscillation circuit and a temperature compensation circuit.
The height H1 of the element mounting pads 10 and 11, the height H2 of the first pillow member 15, and the height H3 of the second pillow member 20 are in a relationship of H1> H3 <H2. For this reason, as will be described below, not only can the crystal vibrating elements with short longitudinal dimensions and width dimensions be cantilevered using the element mounting pads 10 and 11, but also the one element mounting pad and Second pillow member 20
It becomes possible to support both ends using. Further, not only can the quartz crystal resonator element having a long longitudinal dimension and a long width dimension be cantilevered using the element mounting pads 10 and 11, but also the one element mounting pad and the first pillow member 15 can be supported. It becomes possible to support both ends by using.
The quartz resonator element 30 includes, for example, a so-called strip-shaped quartz substrate (piezoelectric substrate) 31 and a quartz substrate 31.
Excitation electrodes 32 formed on both the front and back surfaces of the substrate and lead terminals 33 drawn from the respective excitation electrodes to one edge in the longitudinal direction of the quartz substrate. Each lead terminal 33 is mounted on each element by a conductive adhesive 35. It is electrically connected to the pads 10 and 11.
Since the crystal resonator element 30 according to the example shown in FIGS. 1A and 1B is a cantilever type whose longitudinal dimension and width dimension are short, one end edge in the longitudinal direction is attached to each element mounting pad. 1
By joining with 0 and 11, the other end edge of the free end is in a non-contact state with the upper surface of the second pillow member 20 provided at the intermediate position in the longitudinal direction of the recess. In particular, as a result of the height H3 of the second pillow member 20 being lower than the height of the element mounting pads 10 and 11, contact between the free end portion of the crystal vibrating element 30 and the second pillow member 20 is avoided. can do.

One element mounting pad 10 has a short shape extending from the outer wall 4b ′ on the back side in the recess 6, and the other element mounting pad 11 has a long shape extending from the outer wall 4b ″ on the near side of the recess. That is, the gap G between the inner end edges of the two element mounting pads 10 and 11 is not located at the center of the recess 6 in the width direction B, but is deviated toward the outer wall 4b ′ on the back side. In other words, at least a part (inner end portion) of one of the two element mounting pads (in this example, the element mounting pad 11) is located at the center in the width direction near one end in the longitudinal direction of the insulating substrate. .
For this reason, in the state where the two lead terminals 33 of the crystal vibrating element 30 having a short width direction dimension are appropriately connected to the element mounting pads 10 and 11 in one-to-one correspondence and connected by the conductive adhesive 35. It can be mounted at a deviated position along the outer wall 4b ′.
Further, when the package 3 cantilever-supports a crystal resonator element 30A having a long longitudinal dimension and a width dimension, as shown in FIGS. 2 (a) and 2 (b), one end edge of the crystal resonator element 30 is provided. The two lead terminals 33 positioned in the first and second lead terminals 33 can be mounted on the center portion in the width direction of the recess 6 in a state of being connected to the element mounting pads 10 and 11 in a one-to-one correspondence by the conductive adhesive 35. At this time, by using the thickness of the conductive adhesive 35, the free end-like other end edge of the crystal vibrating element 30 </ b> A can be supported above the first pillow member 15 in a non-contact state.

On the other hand, in the case where the quartz resonator element 30B having a short and both-end-supported lead terminal structure is supported by the package 3, both ends of the crystal resonator element are shown in FIGS. The central portion (including one lead terminal 33) is electrically and mechanically connected and supported to one element mounting pad 11 by the conductive adhesive 35, while the other end edge (the other lead terminal 33 is connected). The conductive adhesive 3 with respect to the conductive pad 21 on the second pillow member 20.
5 is electrically and mechanically connected and supported. At this time, since the height H3 of the second pillow member 20 is lower than the heights H1 and H2 of the element mounting pad 11 and the first pillow member 20, it interferes with the vibration part of the crystal resonator element 30B. There is no possibility of changing the resonance frequency. Since the inner edge of the element mounting pad 11 having an asymmetric shape with the element mounting pad 10 is formed to extend to a position corresponding to the center in the width direction of the recess 6, the width direction of one end edge of the crystal resonator element 30 </ b> B. The central portion can be adhered and held. At the position corresponding to the central portion in the width direction of the other end edge of the crystal resonator element 30B, the second
Since this pillow member 20 is positioned, this portion can be adhered and held.

Further, when the long crystal vibrating element 30C is supported at both ends by the package 3, as shown in FIGS. 4A and 4B, one end of the crystal vibrating element (including one lead terminal 33).
Is connected to and supported by the conductive adhesive 35 on one element mounting pad 11 while the other edge (including the other lead terminal 33) is connected to the first central portion. The conductive pad 16 on the pillow member 15 is electrically and mechanically connected and supported by the conductive adhesive 35.
In addition, since the crystal resonator elements 30B and 30C for supporting both ends have lead terminals 33 extending in opposite directions from the excitation electrodes 32 provided on both the front and back surfaces of the crystal substrate 31, each lead terminal is connected to one element mounting pad. 11 and the second pillow member 20 or the first pillow member 15.
Next, the package 3 according to the present invention holds each of the crystal resonator elements in a circular shape (corresponding to a high frequency), an elliptical shape, and an oval shape in a cantilever manner or a both-end support state in addition to the rectangular crystal resonator element as described above. It is possible.

FIGS. 5A and 5B are a longitudinal sectional view showing an assembly example in the case where both circular quartz crystal vibrating elements 30D are supported, and a plan view showing the inside of the package.
The crystal resonator element 30 </ b> D has a configuration in which excitation electrodes 32 are formed on both main surfaces of a disk-shaped crystal substrate 31, and lead terminals 33 are extended from the respective excitation electrodes 32 in the opposite direction.
One lead terminal 33 is electrically and mechanically connected to the element mounting pad 11 by a conductive adhesive 35, and the other lead terminal 33 is connected to the second pillow member 20 by a conductive adhesive 35. Electrically and mechanically connected.
When the circular crystal resonator element 30D is cantilevered, the crystal resonator element 30D is
It is assumed that the excitation electrodes 32 are formed on both main surfaces of the disk-shaped quartz substrate 31 and the lead terminals 33 are extended from the excitation electrodes 32 in the same direction. The lead terminals 33 and 33 are electrically and mechanically connected to the element mounting pads 10 and 11 by the conductive adhesive 35, and the edge of the quartz substrate on the side where no lead terminal exists is the second pillow. The state is separated from the member 20.
In the above-described embodiment, a crystal oscillator is illustrated as a representative example of a piezoelectric oscillator. However, the present invention can be applied to an oscillator that uses a piezoelectric vibration element made of a piezoelectric material.

DESCRIPTION OF SYMBOLS 1 ... Crystal oscillator, 2 ... Crystal oscillator (piezoelectric vibrator), 3 ... Package, 4 ... Insulating substrate, 4
a ... bottom plate, 4b ... outer wall, 4b "... outer wall, 5 ... mounting terminal, 6 ... recess, 10, 11 ... element mounting pad, 15 ... first pillow member, 16 ... conductive pad, 20 ... second pillow Members, 21 ... conductive pads, 25 ... IC component housing recesses, 26 ... IC component mounting pads, 30 ... crystal resonator elements (piezoelectric resonator elements), 30A ... crystal resonator elements, 30B ... crystal resonator elements, 30C ... crystal resonator elements , 30
D ... Quartz vibrating element, 31 ... Quartz substrate (piezoelectric substrate), 32 ... Excitation electrode, 33 ... Lead terminal,
35 ... conductive adhesive, 40 ... IC component, 50 ... lid member

Claims (3)

Two projecting element mounting pads arranged separately along the width direction near one edge in the longitudinal direction, and a projecting and conductive pad at the center in the width direction near the other end in the longitudinal direction Provided between the pillow member, the second pillow member having a protruding shape and a conductive pad in the central portion in the width direction of the central portion in the longitudinal direction, and the first pillow member and the second pillow member. IC component receiving recess and the IC
An insulating substrate having an IC component mounting pad provided in the component housing recess;
A piezoelectric vibration element mounted on the element mounting pad;
A lid member for hermetically sealing the piezoelectric vibration element;
I having an electrode electrically connected to the IC component mounting pad and constituting an oscillation circuit
C parts,
A piezoelectric oscillator comprising: 2. The piezoelectric oscillator according to claim 1, wherein at least a part of one of the two element mounting pads is located at a central portion in a width direction near one end in a longitudinal direction of the insulating substrate. The height H1 of the element mounting pad, the height H2 of the first pillow member, and the height H3 of the second pillow member are:
3. The piezoelectric oscillator according to claim 1, wherein a relationship of H1> H3 <H2 is satisfied.

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