Crystal device

Abstract

To provide a crystal device capable of improving crystal impedance (CI) characteristics and reducing deterioration due to vibration noise, a crystal vibrator including a crystal device, and a crystal oscillator.SOLUTION: A crystal device includes a package 10 and a blank 20a. The package 10 includes a pedestal 11 on which a blank 20a is mounted. The blank 20a is adhered to the second pattern portions 11a2, 11b2, 11c2, and 11d2 formed on the bottom surface of the recess of the base 11 at four points. A planar area of the blank 20a is 10% or more and 30% or less of a planar area of the package.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a crystal device, and more particularly to a crystal device that improves crystal impedance (CI: Crystal Impedance) characteristics and reduces degradation due to vibration noise.

Background Art

[0002] [Description of Prior Art] Among crystal devices in which a crystal piece is mounted on a ceramic package, there is a crystal device with a pedestal on which the crystal piece is mounted on a pedestal fixed to the package. In some crystal devices with pedestals, the crystal piece and the pedestal are adhesively fixed at four points using an adhesive.

[0003] In such a crystal device with a pedestal, since it has a low acceleration sensitivity specification, it is important to reduce vibration noise, but it is also necessary to design to satisfy crystal characteristics (constants, CI, etc.).

[0004] In recent years, in base stations for 5th generation (5G) communication, which has been rapidly spreading, as the digital and aggregation parts inside are miniaturized, the installation environment has also become diversified. Due to such changes in the installation environment and miniaturization, the influence of vibration caused by wind and cooling fans on the crystal oscillator has become an issue.

[0005] In addition, the progress of information communication such as 4K / 8K video communication, in-vehicle communication devices, and IoT (Internet of Things) is remarkable, and in order to support such high-speed communication, highly stable and high-quality oscillators with little characteristic degradation due to the environment are required.

[0006] [Blank Size and CI Characteristics: FIG. 6] FIG. 6 is an explanatory diagram showing the relationship between the blank (BK) area (size) of a crystal oscillator and CI characteristics. As shown in Figure 6, the smaller the blank size, the worse the CI characteristics (S1), and the larger the blank size, the better the CI characteristics (S1). In Figure 6, the thick line in the center represents the line required for the product (required Spec.), with the area above the thick line indicating that the CI characteristics do not meet the requirements, and the area below the thick line indicating that the CI characteristics meet the requirements. Furthermore, CI variation (S2) shows a similar trend with respect to blank size.

[0007] Generally, the smaller the blank size, the better it is against vibration noise, while the larger the blank size, the more it is affected by vibration noise and deteriorates. In other words, vibration noise characteristics are more favorable with smaller blank sizes, but CI characteristics deteriorate. This shows that there is a trade-off relationship between vibration noise and CI characteristics.

[0008] [Related technologies] Regarding prior art related to a quartz device with a base, there is Japanese Patent Publication No. 2019-057871, "Quartz Device" (Patent Document 1). Patent Document 1 describes a quartz device that uses a base to facilitate the improvement of characteristics and reduction of costs. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2019-057871 [Overview of the project] [Problems that the invention aims to solve]

[0010] As mentioned above, there is a trade-off relationship between vibration noise and CI characteristics depending on the blank size, and there was a problem in designing a crystal device that could improve CI characteristics while suppressing the effects of vibration noise.

[0011] Patent Document 1 does not describe that the CI characteristics can be improved and the deterioration due to vibration noise can be reduced.

[0012] The present invention has been made in view of the above actual situation, and an object thereof is to provide a crystal device that can improve CI characteristics and reduce deterioration due to vibration noise.

Means for Solving the Problems

[0014] To solve the problems of the above conventional example The present invention is A crystal device comprising a crystal blank mounted within a package, the package having a base for mounting the blank and bonding the blank at four points, the inner plane of the package having first patterned sections provided at the four corners and second patterned sections connected to the first patterned sections and extending toward the center of the inner plane, the base being provided and bonded on the second patterned sections, characterized in that the area of the blank surface is 13% or more and 18% or less with respect to the area of the plane specified by the width and depth of the package. no hi

[0016] The present invention is characterized in that a crystal oscillator includes the above crystal device.

[0017] The present invention is characterized in that a crystal oscillator includes an oscillation circuit that amplifies the oscillation frequency signal and the above crystal device.

Effects of the Invention

[0018] According to the present invention, A crystal device comprising a crystal blank mounted within a package, the package having a base for mounting the blank and bonding the blank at four points, the inner plane of the package having first patterned sections provided at the four corners and second patterned sections connected to the first patterned sections and extending toward the center of the inner plane, the base being provided and bonded on the second patterned sections, since the area of the blank surface is no hi % or more 13 and 18 % or less with respect to the area of the plane specified by the width and depth of the package, there is an effect that the CI characteristics can be improved and the deterioration due to vibration noise can be reduced.

Brief Description of the Drawings

[0019] [Figure 1] It is a plan view showing the configuration of a crystal device (1). [Figure 2] It is a plan view showing the configuration of a crystal device (2). [Figure 3] It is a plan view showing the configuration of a crystal device (3). [Figure 4] ]>It is an explanatory view showing vibration noise characteristics.​ [Figure 5] It is an explanatory diagram showing CI characteristics. [Figure 6] It is an explanatory diagram showing the blank size and CI characteristics.

Embodiments for Carrying Out the Invention

[0020] Embodiments of the present invention will be described with reference to the drawings. [Outline of Embodiment] The crystal device (this crystal device) according to the embodiment of the present invention includes a pedestal on which a crystal piece (blank) is mounted in a package. The blank is adhered to the pedestal at four points, and the area of the plane of the mounting surface of the blank is 10% or more and 30% or less with respect to the area of the plane specified by the width and depth of the package. It can improve the CI characteristics and reduce the deterioration due to vibration noise.

[0021] In particular, it is more effective that the area of the plane of the blank is 13% or more and 18% or less with respect to the area of the plane of the package of the crystal device.

[0022] [Configuration of This Crystal Device: FIGS. 1 to 3] This crystal device will be described with reference to FIGS. 1 to 3. FIG. is a plan view showing the configuration of the crystal device (1), FIG. 2 is a plan view showing the configuration of the crystal device (2), and FIG. 3 is a plan view showing the configuration of the crystal device (3). This crystal device has a package with a size of width (W) 3.2 mm, depth (D) 2.5 mm, and height (H) 0.72 mm. The ratio of the area of the plane of the mounting surface of the blank (hereinafter simply referred to as "the plane of the blank") to the area of the plane of the package specified by the width and depth (hereinafter simply referred to as "the plane of the package") (3.8 mm × 2.5 mm) is 10% or more and 30% or less.

[0023] In the crystal device (1), the blank will be described as 20a, in the crystal device (2) as 20b, and in the crystal device (3) as 20c, but they may be collectively referred to as 20.

[0024] [Crystal device (1): Figure 1] The first device (crystal device (1)) in this crystal device will be explained with reference to Figure 1. As shown in Figure 1, the crystal device (1) has a recess inside the package 10, and first pattern portions 11a1, 11b1, 11c1, 11d1 and second pattern portions 11a2, 11b2, 11c2, 11d2 are formed on the bottom surface of the recess, a base 11 is provided on the second pattern portions 11a2, 11b2, 11c2, 11d2, a crystal piece (blank) 20a is provided on the base 11, and the blank 20a is fixed to the second pattern portions 11a2, 11b2, 11c2, 11d2 via the base 11 by adhesive 30. In other words, the blank 20a is bonded to the surface of the base 11 at four points, and adhesive 30 is applied to the back surface of the base 11 to the second pattern sections 11a2, 11b2, 11c2, and 11d2.

[0025] Package 10 has a structure in which insulating materials such as ceramics are laminated and has a recess for housing the blank 20a. The base 11 is formed from the same material as the package 10 or from an insulating material such as quartz, and the blank 20a is mounted on it via the second pattern sections 11a2, 11b2, 11c2, and 11d2.

[0026] The first pattern sections 11a1, 11b1, 11c1, and 11d1 are formed in a roughly rectangular shape at the four corners of the plane of the recess (storage section) inside the package 10, with 11a1 connected to the corner of the nearest recess and 11c1 connected to the corner of the nearest recess, and from these corners connected to the wiring pattern. Furthermore, the second pattern portions 11a2, 11b2, 11c2, and 11d2 are connected to the corners of the first pattern portions 11a1, 11b1, 11c1, and 11d1 near the center of the plane, forming a roughly rectangular shape. In other words, the second pattern portions are formed to extend from the first pattern portions toward the center of the plane. Furthermore, the second pattern section 11a2 and the second pattern section 11d2 are connected along the long side of the base 11. The second pattern section 11b2 and the second pattern section 11c2 are connected along the long side of the base 11. The adhesive 30 is either a conductive adhesive or a non-conductive adhesive, and it fixes the blank 20a to the second pattern sections 11a2, 11b2, 11c2, and 11d2 via the base 11.

[0027] The blank 20a has a roughly rectangular shape, with an excitation electrode 21a formed on its surface and an excitation electrode 21b formed on its back surface. The lead-out portion 22a of the surface excitation electrode 21a is drawn out in the direction of the short side on the left side of Figure 1. Although the excitation electrode 21b on the back side is not visible in Figure 1, the pull-out portion 22b is pulled out in the direction of the short side on the left.

[0028] The blank 20a is fixed in place by adhesive 30 at two points on the left side of the second pattern section 11a2, 11b2 and at two points on the right side of the second pattern section 11c2, 11d2. Furthermore, the first pattern section 11a1 is connected to the wiring pattern at the corner of the recess (the lower left corner in Figure 1), and the second pattern section 11b2 is connected to the wiring pattern at the corner of the recess (the upper right corner in Figure 1) via the second pattern section 11c2 and the first pattern section 11c1. The excitation electrodes 21a and 21b formed on the blank 20a are connected to the second pattern sections 11a1 and 11b1 via conductive adhesive at their lead-out portions 22a and 22b, and finally to the wiring pattern. The wiring pattern is then connected to the IC for oscillation. The connection between the blank 20a and the second pattern sections 11c2 and 11d2 may be made with a non-conductive adhesive.

[0029] Here, the plane of package 10 has an area of ​​3.2 mm × 2.5 mm, and the plane of the blank 20a of the crystal device (1) has an area of ​​0.975 mm × 1.240 mm. Therefore, the ratio of the area of ​​the blank 20a to the area of ​​the package 10 is approximately 15.1%.

[0030] [Crystal device (2): Figure 2] The second device in this crystal device (crystal device (2)) is almost identical to the crystal device (1) shown in Figure 1, but the blank 20b on which it is mounted has been miniaturized. With the miniaturization of the blank 20b, the excitation electrodes 21a, 21b and the extraction electrodes 22a, 22b have also been miniaturized.

[0031] Here, the plane of package 10 has an area of ​​3.2 mm × 2.5 mm, and the plane of the blank 20b of the crystal device (2) has an area of ​​0.852 mm × 0.968 mm. Therefore, the ratio of the plane area of ​​blank 20b to the plane area of ​​package 10 is approximately 10.3%.

[0032] [Crystal device (3): Figure 3] The third device in this crystal device (crystal device (3)) has a wider (larger) blank 20c than crystal device (1) in Figure 1, as shown in Figure 3. Of course, the blank 20c is small enough to fit into the recess of package 10. Due to the increased size of the blank 20c, the second pattern section is omitted, and the first pattern sections 11a1, 11b1, 11c1, and 11d1 are provided on the surface of the bottom of the recess. Then, rectangular electrode patterns 11a3, 11b3, 11c3, and 11d3 are formed on the front and back of the four corners of the base 11 which is mounted on the first pattern sections 11a1, 11b1, 11c1, and a blank 20c is mounted on the base 11, with pull-out sections 22a and 22b connected to the electrode patterns 11a3 and 11b3.

[0033] Here, the plane of package 10 has an area of ​​3.2 mm × 2.5 mm, and the plane size of the blank 20c of the crystal device (3) has an area of ​​1.252 mm × 1.800 mm. Therefore, the ratio of the plane area of ​​the blank 20c to the plane area of ​​package 10 is approximately 28.2%.

[0034] [Vibration noise characteristics: Figure 4] Next, the vibration noise characteristics of this crystal device will be explained with reference to Figure 4. Figure 4 is an explanatory diagram showing the vibration noise characteristics. Figure 4(1) shows the vibration noise characteristics of crystal device (1) in Figure 1, Figure 4(2) shows the vibration noise characteristics of crystal device (2) in Figure 2, and Figure 4(3) shows the vibration noise characteristics of crystal device (3) in Figure 3.

[0035] In Figure 4, the area enclosed by the ellipse represents spurious emissions. The crystal device with the smallest blank size (2) does not generate spurious emissions and exhibits good vibration noise characteristics. Next, although the crystal device (1) generates spurious emissions, it has smaller spurious emissions and better vibration noise characteristics compared to the crystal device (3) with the largest blank size. In other words, the vibration noise characteristics improve in the order of crystal device (3), crystal device (1), and crystal device (2).

[0036] [CI Characteristics: Figure 5] Next, the CI characteristics of this crystal device will be explained with reference to Figure 5. Figure 5 is an explanatory diagram showing the CI characteristics. Figure 5(1) shows the CI characteristics of crystal device (1) in Figure 1, Figure 5(2) shows the CI characteristics of crystal device (2) in Figure 2, and Figure 5(3) shows the CI characteristics of crystal device (3) in Figure 3. In each figure in Figure 5, the horizontal axis represents the resistance value [Ω], and the vertical axis represents the frequency (number of occurrences) at that resistance value.

[0037] In Figure 5, the crystal device with the best CI characteristics is (3) in Figure 5(3), followed by (1) in Figure 5(1), and finally (2) in Figure 5(2).

[0038] As described above, the order from best to worst in terms of vibration noise characteristics is crystal device (2), crystal device (1), and crystal device (3), while the order from best to worst in terms of CI characteristics is crystal device (3), crystal device (1), and crystal device (2). Therefore, the crystal device with good vibration noise characteristics and good CI characteristics is crystal device (1). The crystal device (1) has a blank size of width (horizontal) 1,240 mm x depth (vertical) 0.975 mm with an area of ​​1,209 mm². 2 ) and the package has an area of ​​3.2mm width (horizontal) x 2.5mm depth (vertical) (8mm 2 Therefore, the ratio of the area of ​​the blank 20a plane to the area of ​​the package 10 plane is approximately 15.1%. If this ratio is between approximately 13% and 18%, then an effect almost identical to that of the crystal device (1) can be obtained.

[0039] Furthermore, the ratio of the planar area of ​​the blank 20 to the planar area of ​​the package 10 can be arbitrarily determined within a range of approximately 10% to 30%, taking into consideration the balance between vibration noise characteristics and CI characteristics, and including the crystal devices (1) to (3).

[0040] [Applications to products] In this embodiment, a quartz crystal oscillator was used as an example, but this method can also be applied to oscillators in which an IC is mounted on the underside of a base 11 within a recess in the package 10, or to oscillators in which a blank 20 is mounted in one of the two recesses of an H-type package and an IC is mounted in the other. For example, it can be applied to TCXO (Temperature Compensated Crystal Oscillator), ICXO (Clock Crystal Oscillator), SPXO (Simple Packaged Crystal Oscillator), and VCXO (Voltage Controlled Crystal Oscillator).

[0041] [Effects of the embodiment] According to this crystal device, the package 10 is equipped with a base 11 on which a blank 20 is mounted. The blank 20 is bonded at four points via the base 11 to the second patterns 11a2, 11b2, 11c2, and 11d2 formed on the bottom surface of the recess. The area of ​​the mounting surface of the blank 20 is set to be between 10% and 30% of the area of ​​the plane specified by the width and depth of the package 10, thereby improving CI characteristics and reducing degradation due to vibration noise.

[0042] In particular, this crystal device has the advantage of further improving CI characteristics and reducing degradation due to vibration noise, as the planar area of ​​the blank 20 is set to 13% to 18% of the planar area of ​​the package 10. [Industrial applicability]

[0043] This invention is suitable for quartz devices that can improve CI characteristics and reduce degradation due to vibration noise. [Explanation of Symbols]

[0044] 10…Package, 11…Base, 11a1,11b1,11c1,11d1…First pattern section, 11a2,11b2,11c2,11d2…Second pattern section, 11a3,11b3,11c3,11d3…Electrode pattern, 20,20a,20b,20c…Crystal piece (blank), 21a,21b…Excitation electrode, 22a,22b…Drawer section, 30…Adhesive

Claims

1. A crystal device that incorporates a crystal blank within the package, The base is equipped with the aforementioned blank and the blank is bonded at four points, The inner surface of the package has first pattern sections provided at the four corners, and second pattern sections connected to the first pattern sections and extending toward the center of the inner surface. The base is provided and bonded on the second pattern portion. A crystal device characterized in that the area of ​​the blank plane is 13% or more and 18% or less of the area of ​​the plane specified by the width and depth of the package.

2. A quartz oscillator characterized by comprising the quartz device described in claim 1.

3. A crystal oscillator comprising an oscillation circuit for amplifying an oscillation frequency signal and the crystal device described in claim 1.

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