JP2012129904A - Electronic apparatus - Google Patents

Abstract

An electronic device including a resonator element and having a small size, a low frequency, and a high Q value is provided.
A vibrating piece 20 provided in an electronic device includes a base portion 21 having a pair of cuts 31 and a pair of vibrating arms 22 extending in parallel from one end side of a first portion of the base portion 21. ,have. Each vibrating arm 22 has a general portion 23 that is a main vibrating portion, and a weight portion 29 that is wider than the general portion 23 on the tip side opposite to the base of the vibrating arm 22 with the base 21. is doing. Further, the base portion is formed on the distal end side of the vibrating arm 22 opposite to the base of the bottom portion of the vibrating arm and the base portion of the vibrating arm along at least one main surface of the main surfaces. A weight portion 29 having a width wider than that of the base side is formed. The weight portion 29 is formed such that, in the longitudinal direction of the vibrating arm 22, the length ratio of the weight portion 29 occupying the length from the base to the distal end side with the base portion 21 is in a range of 35% to 41%. .
[Selection] Figure 1

Description

  The present invention relates to an electronic apparatus including a vibrating piece such as a bending vibrating piece that vibrates in a bending vibration mode.

  Conventionally, for a vibrating piece that vibrates in a bending vibration mode and can be provided in an electronic device, for example, a pair of vibrating arms are extended in parallel from the base of a base material made of a piezoelectric material such as quartz, and Tuning-fork-type bending vibration pieces that vibrate in directions toward or away from each other in the horizontal direction are widely used. When the vibration arm of the tuning-fork type bending vibration piece is excited, if the vibration energy is lost, it causes a decrease in the performance of the vibration piece, such as an increase in CI (Crystal Impedance) value and a decrease in Q value. Therefore, various ideas have been conventionally made in order to prevent or reduce such loss of vibration energy.

  For example, there are known tuning-fork type crystal vibrating pieces in which cut portions or cuts (cut grooves) having a predetermined depth are formed on both sides of a base portion from which a vibrating arm extends (for example, Patent Document 1 and Patent Document 2). reference). This tuning-fork type crystal resonator element controls the Q value by enhancing the confinement effect of vibration energy by mitigating the leakage of vibration from the base by cutting when the vibration of the vibrating arm also includes a vertical component. In addition, variations in the Q value between the resonator elements are prevented.

In the resonator element, not only the loss of mechanical vibration energy as described above, but also the temperature generated between the compressive portion where the compressive stress of the vibrating arm which is bent and acting and the extension portion where the tensile stress acts. It is also caused by heat conduction due to the difference. This decrease in the Q value caused by heat conduction is called a thermoelastic loss effect.
In order to prevent or suppress a decrease in the Q value due to the thermoelastic loss effect, a tuning-fork type vibration piece in which a groove or a hole is formed on the center line of a vibrating arm (vibrating beam) having a rectangular cross section is disclosed in Patent Document 3, for example. It has been introduced.

By the way, various electronic devices including a resonator element, for example, a small information device such as an HDD (hard disk drive), a mobile computer, or an IC card, or a mobile body such as a mobile phone, a car phone, or a paging system. In recent years, miniaturization of communication devices, vibration gyro sensors, and the like has progressed more and more. In connection with this, the request | requirement of size reduction of the vibration piece attached to those electronic devices has increased further.
Among the demands for downsizing of the resonator element, in particular, reducing the length of the vibrating arm has a high contribution rate, and accordingly, it is required to reduce the cross-sectional area of the vibrating arm. . For this reason, it is known that it is difficult to lower the frequency of the resonator element, and the vibration characteristics of the resonator element are likely to become unstable due to the occurrence of a higher-order vibration mode. As a resonating piece that can suppress the occurrence of such higher-order vibration modes and can reduce the frequency and stabilize vibration characteristics, the tip of the resonating arm is wider than the general part (arm part) of the resonating arm. For example, Patent Literature 4 introduces a resonator element in which a weight portion is formed.

JP 2002-261575 A Japanese Patent Laid-Open No. 2004-260718 Japanese Utility Model Publication No. 2-3322 Japanese Utility Model Publication No. 2005-5896

  However, when the vibrating piece that can be provided in the electronic device has a vibrating arm that has both the long groove and the weight portion, the occupation ratio of the length of the weight portion with respect to the entire length in the longitudinal direction of the vibrating arm is too small. The inventor has found that the effect of reducing the frequency by the weight portion and suppressing the thermoelastic loss by the long groove cannot be achieved at a desired level if the weight is too large or too large. Further, the inventor has a desired Q value due to a desired low frequency and a thermoelastic loss suppression effect when the occupation ratio of the length of the weight portion with respect to the entire length in the longitudinal direction of the vibrating arm is within a certain range. It was found that it can be secured.

  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 An electronic apparatus according to this application example includes a resonator element and a circuit unit electrically connected to the resonator element, and the resonator element extends from the base part and the base part. A resonating arm, and the resonating arm is provided with a bottomed long groove having an opening along at least one of the main surfaces of the resonating arm. A weight portion having a width wider than the base side of the vibrating arm and the base side of the vibrating arm is provided on the tip side opposite to the base of the base of the arm, and in the longitudinal direction of the vibrating arm, The ratio of the length of the weight part to the length from the tip side to the tip side is in the range of 35% to 41%.

  According to this configuration, in the resonator element provided in the electronic device, the vibration efficiency is improved and the CI value is reduced by the long groove provided in the resonator arm, and the weight portion of the tip portion of the resonator arm is By fulfilling the function, it is possible to obtain the effect of suppressing the frequency sufficiently low without increasing the length of the vibrating arm, and the effect of sufficiently reducing the Q value by reducing the thermoelastic loss. The inventor has found that Accordingly, it is possible to provide a resonator element having excellent vibration characteristics while achieving a reduction in frequency while achieving a reduction in size and suppressing a decrease in the Q value. As a result, it is possible to promote downsizing of electronic devices and improve reliability.

  Application Example 2 In the electronic device according to the application example described above, the length ratio of the weight portion is in a range of 36% to 40%.

  According to this configuration, the effects of downsizing, lowering the frequency, and suppressing the decrease in the Q value become significant.

  Application Example 3 In the electronic device according to the application example described above, the length ratio of the weight portion is in a range of 37% to 39%.

  According to this configuration, the effects of downsizing, lowering the frequency, and suppressing the decrease in the Q value become more prominent.

  Application Example 4 In the electronic device according to the application example described above, the vibrating piece includes the two vibrating arms extended from the base and the two vibrating arms of the base between the vibrating arms of the vibrating arm. And a support arm that extends along the longitudinal direction.

According to this configuration, since the vibrating piece provided in the electronic device is provided with the support arm between the pair of vibrating arms, particularly when the vibrating arms vibrate, the vibrating arms approach each other. When the vibration is caused to occur, the change in the operating parameter of the resonator element caused by the air between the vibrating arms being disturbed can be suppressed.
In addition, various problems that occur when the base is supported and fixed to a package or the like with the base as a support, for example, the tip of the vibrating piece can be prevented from tilting downward and touching the package or the impact on the package can be prevented. Therefore, it is possible to avoid an abnormal operation that may occur by being directly transmitted to the vibrating arm via the arm, and to provide a vibrating piece with stable vibration characteristics. An electronic device provided with this resonator element can maintain high reliability.

  Application Example 5 In the electronic device according to the application example, the base portion and the vibrating arm of the vibrating piece are formed of quartz.

  According to this configuration, it is possible to provide a quartz crystal resonator element that has high impact resistance and has excellent vibration characteristics in which a decrease in Q value due to thermoelastic loss is suppressed. The electronic device provided with this crystal vibrating piece can maintain higher reliability.

  Application Example 6 In the electronic device according to the application example described above, the vibration piece is a bending vibration piece exhibiting a bending vibration mode.

  According to this configuration, the inventor has found that the bending vibration piece that can be provided in an electronic device and exhibits a bending vibration mode exhibits the effect of suppressing the decrease in the Q value at the same time as lowering the frequency.

(A) is a top view of one main surface side schematically explaining one embodiment of a resonator element provided in the electronic apparatus according to the present invention, and (b) is a cross-sectional view taken along line AA in (a). FIG. Fig. 4 is a graph showing the relationship between the weight portion occupancy rate of the vibrating piece and the high performance index. (A) is a schematic plan view explaining one Embodiment of the vibrator | oscillator provided with the said vibration piece from the top, (b) is the BB sectional drawing of (a). FIG. 4A is a schematic plan view illustrating an embodiment of an oscillator including the resonator element as viewed from above, and FIG. 4B is a cross-sectional view taken along the line CC of FIG. The perspective view which shows the outline of the mobile telephone as an example of an electronic device. The circuit block diagram of a mobile telephone. The perspective view which shows the outline of the personal computer as an example of an electronic device.

Hereinafter, an electronic device according to an embodiment of the present invention will be described with reference to the drawings. This electronic device is characterized by including a resonator element having excellent vibration characteristics.
(Embodiment)

[Vibration piece]
First, prior to the description of the electronic device of the present invention, a resonator element provided in the electronic device will be described.
1A and 1B schematically illustrate a resonator element according to the present embodiment. FIG. 1A is a plan view of one main surface side, and FIG. 1B is a cross-sectional view taken along line AA in FIG. It is a cross-sectional enlarged view.
In FIG. 1A, the resonator element 20 of the present embodiment is a resonator element exhibiting a bending vibration mode made of a piezoelectric material such as crystal, lithium tantalate, or lithium niobate. When the resonator element 20 is made of quartz, the quartz wafer is cut out by rotating it in the range of 0 to 5 degrees clockwise around the Z axis in an orthogonal coordinate system consisting of the X, Y, and Z axes. A crystal Z plate obtained by cutting and polishing to a predetermined thickness is used. The resonator element 20 according to the present embodiment includes a base portion 21 formed by processing the quartz crystal Z plate and a pair of base portions 21 extending in parallel with each other from one end side (upper end side in the drawing). This is a crystal vibrating piece having a so-called tuning-fork type outer shape composed of the vibrating arm 22.

The base portion 21 is formed with a pair of cuts 31 in the opposing direction along one straight line so that a shape confined to both the main surfaces appears. The base portion 21 includes a first portion 21a and a second portion 21b that are located on both sides of the pair of cuts 31, and a connection portion that connects the first portion 21a and the second portion 21b between the pair of cuts 31. 21c. In the vibrating piece 20 of the present embodiment, the transmission of vibration of each vibrating arm 22 is blocked by the notch 31, so that so-called vibration leakage that the vibration is transmitted to the outside via the base 21 and the support arm 30 is suppressed, An increase in CI value can be prevented.
In addition, it is desirable that each notch 31 is adjusted to an optimal width and length after securing the strength against dropping of the vibrating piece 20 to minimize vibration leakage.

As shown in FIG. 1A, the pair of vibrating arms 22 extends from the first portion 21 a of the base portion 21 in parallel to both main surfaces (upper and lower surfaces in the drawing). Each resonating arm 22 has both the main surfaces and both side surfaces connecting the main surfaces on both sides.
Each vibrating arm 22 has a general portion 23 that is a main vibrating portion in the vibrating arm 22 at the center thereof. In addition, each vibrating arm 22 is gradually widened at the base portion connected to the base portion 21 from the general portion 23 toward the base portion 21 side, and is widest at the base portion with the base portion 21. A wide portion 24 is provided. Thus, since each vibrating arm 22 has the wide portion 24, it is connected to the base portion 21 with a wide width, so that rigidity is increased and impact resistance and the like are improved.

Further, a weight portion 29 having a width wider than that of the general portion 23 is formed on the distal end side of the vibrating arm 22 opposite to the base of the base portion 21. As described above, since the weight portion 29 is provided at the tip portion of each vibrating arm 22, the tip portion functions as a weight, so that the frequency can be lowered without increasing the length of the vibrating arm 22. it can.
Further, in the longitudinal direction of each vibrating arm 22 of the vibrating piece 20 (in this example, the direction in which each vibrating arm 22 extends from the first portion 21a of the base portion 21), the length from the base to the distal end side with the base portion 21 is long. The length l of the weight portion 29 occupying the length L is adjusted to be in the range of 35% to 41%. By adopting such a configuration, the vibration piece 20 has a sufficiently low frequency without increasing the length of the vibrating arm 22 because the weight portion 29 at the tip of each vibrating arm 22 functions as a weight. The inventor has found that the effect of being suppressed can be obtained and the effect of sufficiently reducing the decrease in the Q value by reducing the thermoelastic loss (details will be described later).

One main surface of each vibrating arm 22 is provided with one bottomed long groove 26a along each longitudinal direction. Further, as shown in FIG. 1B, one long groove is also formed along the longitudinal direction of the vibrating arm 22 on the other main surface of one vibrating arm 22 (on the left side in FIG. 1A). 26b is provided. Similarly, although not shown, one bottomed groove 26b is also provided on the other main surface of the other vibrating arm 22 (the vibrating arm on the right side in the drawing). In other words, each of the long grooves 26a and 26b has an opening located along the main surface.
As described above, the long grooves 26a and 26b provided in each vibration arm 22 reduce the rigidity and easily vibrate, and the vibration arm 22 can efficiently vibrate and exhibit good vibration characteristics. Further, the long grooves 26a and 26b are caused by the temperature rise and the temperature drop generated at the jetty portions 25 on both side surfaces of the vibrating arm 22 due to the distortion caused by the vibration in the vicinity of the base portion of the vibrating arm 22 with the base 21. Since the heat flow path is narrowed, the effect of reducing heat elastic loss by suppressing heat transfer is exhibited, and as a result, adverse effects due to thermoelastic loss such as an increase in CI value and a decrease in Q value can be suppressed.

  The vibration piece 20 of the present embodiment has a pair of support arms 30 extending from the second portion 21 b of the base portion 21. The pair of support arms 30 intersect with the direction in which the pair of vibrating arms 22 extend from the base portion 21 and extend in opposite directions to each other, and then bend at a substantially right angle at the bent portion 32. The vibrating arm 22 extends in a direction parallel to the extending direction. By bending in this way, the vibration piece 20 having the support arm 30 can be reduced in size. The support arm 30 includes a fixed region that is attached to a package or the like, as will be described later, on the tip side of the bent portion 32 (the weight portion 29 side of the vibrating arm 22). By attaching so as to support, the vibrating arm 22 and the base portion 21 can be lifted from the fixed surface of the vibrating piece 20.

  Excitation electrodes 33 and 34 are formed on the surfaces including the long grooves 26a and 26b of the vibrating arms 22 and the both side surfaces (see FIG. 1B). In one vibrating arm 22, the vibrating arm 22 is vibrated by applying a voltage between the excitation electrodes 33 and 34 to expand and contract both side surfaces of the vibrating arm 22. The excitation electrodes 33 and 34 are formed by etching the quartz crystal to form an outer shape including the long grooves 26a and 26b of the resonator element 20, and then depositing nickel (Ni) or chromium (Cr) thereon as an underlayer, for example. Alternatively, an electrode layer made of, for example, gold (Au) can be formed by sputtering and then patterned by photolithography. Here, it is known that chromium has high adhesion to quartz, and gold has low electrical resistance and is difficult to oxidize.

Here, the effect of the resonator element 20 of the present embodiment will be described.
The inventor firstly occupies the occupancy ratio that can efficiently reduce the frequency when the occupancy ratio of the length l of the weight portion 29 to the length L from the base portion 21 to the tip end portion of the vibrating arm 22 is changed. The occupancy ratio that can efficiently reduce the decrease in the Q value converted to a constant frequency was obtained individually by simulation. As a result, the occupancy that can efficiently reduce the frequency does not match the occupancy that can efficiently reduce the decrease in the Q value.
Next, due to the occupancy ratio of the length of the weight portion 29 with respect to the length from the base to the tip of the base portion 21 of the vibrating arm 22, an element that improves the efficiency of reducing the frequency of the vibrating piece 20, The result shown in the graph of FIG. 2 was obtained as a result of multiplying by an element with a smaller elastic loss and further correcting to match the optimum value obtained by simulating with an equivalent model.
In FIG. 2, the horizontal axis represents the weight occupation ratio (%) occupied by the length l of the weight portion 29 with respect to the length L in the longitudinal direction from the base to the tip of the base portion 21 of the vibrating arm 22. The axis is a modified high performance index defined (after correction) as a value obtained by multiplying the low frequency index and the high Q index.
As shown in the graph of FIG. 2, the inventor has found that the high performance index after correction is highest when the weight occupation ratio is 35% to 41% centering on the weight occupation ratio 38%.

The frequency reduction index is a value indicating the amount of frequency decrease due to the weight portion, and is a normalized value of 0 to 1. Specifically, the frequency reduction index is defined as 1 when the frequency is lowest and 0 when it is highest when the weight occupation ratio is changed between 0% and 100%. It is a converted value.
Further, the high Q value index is a value indicating an increase amount of the Q value by the weight portion, and is a normalized value of 0 to 1. Specifically, the high Q value index is 1 when the Q value is the highest and 0 when the weight occupancy is changed between 0% and 100%. As a standardized value.

Therefore, according to the resonator element 20 of the above-described embodiment, the vibration efficiency is improved and the CI value is reduced by the long grooves 26 a and 26 b provided in each vibration arm 22, and at the tip portion of each vibration arm 22. Since the length l in the longitudinal direction of the weight portion 29 is formed to be 35 to 41% of the total length L of the vibrating arm 22, the frequency without increasing the length of the vibrating arm 22. Can be suppressed sufficiently low, and the thermoelastic loss can be reduced to sufficiently suppress the decrease in the Q value.
The inventor has found that this effect is further enhanced if the weight portion occupation ratio of the weight portion 29 of each vibrating arm 22 is set to 36% to 40%.
Furthermore, the inventor has found that this effect is more markedly increased when the weight portion occupancy of the weight portion 29 of each vibrating arm 22 is 37% to 39%.

[Vibrator]
Next, a vibrator using the vibrating piece 20 will be described.
FIGS. 3A and 3B illustrate an embodiment of a vibrator on which the resonator element 20 is mounted. FIG. 3A is a schematic plan view seen from above, and FIG. 3B is a cross-sectional view taken along line BB in FIG. It is. 3A illustrates a state in which a lid 119 (see FIG. 3B) provided above the vibrator 200 is removed for convenience of explaining the internal structure of the vibrator.

  In FIG. 3, the vibrator 200 has a package 110 provided with a recess having a step. The resonator element 20 is joined to the concave bottom portion of the concave portion of the package 110, and a lid 119 as a lid is joined to the open upper end of the package 110.

  The package 110 is formed by laminating a rectangular annular second layer substrate 112 and a third layer substrate 113 having different sizes of inner annular portions on a flat plate-like first layer substrate 111 in this order. A recess having an opening on the side and a step in the interior is formed. As a material of the package 110, for example, ceramic, glass, or the like can be used.

In the recess of the package 110, a plurality of resonator element connection terminals 115 to which the resonator element 20 is bonded are provided on the step formed by the second layer substrate 112. Although not shown, external mounting terminals for joining to an external substrate are provided on the outer bottom surface of the first layer substrate 111 serving as the outer bottom surface of the package 110.
As described above, the various terminals provided in the package 110 are connected to each other by inter-layer wirings such as routing wirings and through holes (not shown).

  The resonator element 20 is bonded to the recess of the package 110. Specifically, the external connection electrode (not shown) provided on a part of the support arm 30 of the resonator element 20 and the recess of the package 110 are provided on a step formed by the protrusion 112 a of the second layer substrate 112. The vibration piece connection terminals 115 are aligned with each other and joined together by a conductive joining member 96 such as a silver paste and electrically connected thereto. As a result, the resonator element 20 is fixed with the vibrating arm 22 as a free end while leaving a gap between the resonator element 20 and the first layer substrate 111 that is the concave bottom portion of the recess in the package 110.

  As shown in FIG. 3B, a lid 119 as a lid is disposed on the upper end of the package 110 to which the resonator element 20 is joined in the recess, and seals the opening of the package 110. As a material of the lid 119, for example, a metal such as 42 alloy (an alloy containing 42% nickel in iron) or Kovar (an alloy of iron, nickel, and cobalt), ceramics, glass, or the like can be used. For example, the lid 119 made of metal is joined to the package 110 by seam welding via a seal ring 118 formed by punching a Kovar alloy or the like into a rectangular ring shape. An internal space formed in the package 110 is a space for the vibration piece 20 to operate. The internal space is hermetically sealed in a reduced pressure space or an inert gas atmosphere.

  According to the vibrator 200 having the above-described configuration, since the resonator element 20 having the above-described configuration is provided, the long grooves 26a and 26b provided in the vibrating arm 22 improve the vibration efficiency and reduce the CI value. Thus, it is possible to provide the vibrator 200 having excellent vibration characteristics in which the low frequency and the high Q value are achieved by the weight portion 29.

[Oscillator]
Next, an oscillator using the vibrating piece 20 will be described.
FIGS. 4A and 4B illustrate an embodiment of an oscillator on which the resonator element 20 is mounted. FIG. 4A is a schematic plan view seen from above, and FIG. 4B is a cross-sectional view taken along the line CC in FIG. is there. FIG. 4A shows a state in which the lid 219 provided above the oscillator 300 is removed for convenience of explaining the internal structure of the oscillator.

  In FIG. 4, the oscillator 300 has a package 210 provided with a recess having a step. The IC chip 150 and the vibrating piece 20 disposed above the IC chip 150 are joined to the concave bottom portion of the concave portion of the package 210, and a lid 219 as a lid is joined to the open upper end of the package 210. Has been.

  The package 210 is formed by laminating a rectangular annular second layer substrate 212, a third layer substrate 213, and a fourth layer substrate 214 having different inner annular portions in this order on a flat first layer substrate 211. By being configured, a recess having an opening on the upper surface side and a step in the inside is formed. As a material of the package 210, for example, ceramic, glass, or the like can be used.

A die pad 215 on which the IC chip 150 is disposed is provided on the first layer substrate 211 which is a concave bottom portion of the concave portion of the package 210. Although not shown, an external mounting terminal for joining to an external substrate is provided on the outer bottom surface of the first layer substrate 211 that is the outer bottom surface of the package 210 (a surface different from the surface on which the die pad 215 is provided). ing.
A plurality of IC connection terminals 216 for electrical connection with the IC chip 150 are provided on the step formed by the second layer substrate 212 in the recess of the package 210.
Furthermore, a plurality of vibration piece connection terminals 217 to which the vibration piece 20 is bonded are provided on the step formed by the third layer substrate 213 in the recess of the package 210.
In the above-described various terminals provided in the package 210, corresponding terminals are connected to each other by an intra-layer wiring such as a lead wiring or a through hole (not shown).

  The IC chip 150 is a semiconductor circuit element (circuit unit) including an oscillation circuit that oscillates the resonator element 20 and a temperature compensation circuit. The IC chip 150 is bonded and fixed to the die pad 215 provided at the bottom of the concave portion of the package 210 by, for example, a brazing material 95. In the present embodiment, the IC chip 150 and the package 210 are electrically connected using a wire bonding method. Specifically, a plurality of electrode pads 155 provided on the IC chip 150 and corresponding IC connection terminals 216 of the package 210 are connected by bonding wires 97.

  In the recess of the package 210, the resonator element 20 is bonded above the IC chip 150. Specifically, the external connection electrode (not shown) provided on a part of the support arm 30 of the resonator element 20 and the step formed by the protrusion 213a of the third layer substrate 213 in the recess of the package 210 are provided. The vibrating piece connection terminal 217 is aligned, and is joined and electrically connected by a conductive joining member 96 such as a silver paste. Accordingly, the vibrating piece 20 is fixed with the vibrating arm 22 as a free end while leaving a gap between the vibrating piece 20 and the IC chip 150 bonded downward in the package 210.

  As shown in FIG. 4B, a lid 219 is disposed at the upper end of the package 210 in which the IC chip 150 and the resonator element 20 are joined in the recess, and the opening of the package 210 is sealed. For example, when a lid 219 made of metal is used, it is joined to the package 210 by seam welding via a seal ring 218 formed by punching a Kovar alloy or the like into a rectangular ring shape. An internal space serving as a space for operating the resonator element 20 in the package 210 is hermetically sealed in a reduced pressure space or an inert gas atmosphere.

  According to the oscillator 300 having the above-described configuration, since the resonator element 20 having the above-described configuration is provided, the long grooves 26a and 26b provided in the vibrating arm 22 improve the vibration efficiency and reduce the CI value. It is possible to provide the oscillator 300 having excellent oscillation characteristics by reducing the frequency and increasing the Q value by the weight portion 29.

〔Electronics〕
The resonator element 20 of the above embodiment can be applied to various electronic devices, and these electronic devices have high reliability. Note that the vibrator 200 and the oscillator 300 described in the above embodiment may be used for the electronic apparatus. 5 and 6 show a mobile phone as an example of the electronic apparatus of the present invention. FIG. 5 is a perspective view showing an outline of the appearance of the mobile phone, and FIG. 6 is a circuit block diagram for explaining the circuit configuration of the mobile phone. The cellular phone 400 will be described using an example using the resonator element 20 (FIG. 1), and the description and description of the configuration and operation of the resonator element 20 will be omitted by using the same reference numerals.
As shown in FIG. 5, the mobile phone 400 is provided with an LCD (Liquid Crystal Display) 401 as a display unit, a key 402 as an input unit for numbers, a microphone 403, a speaker 411, and the like. As shown in FIG. 6, when transmitting by mobile phone 400, when the user inputs his / her voice to microphone 403, the signal is pulse width modulation / coding block 404 and modulator / demodulator block. 405, and further transmitted from the antenna 408 via the transmitter 406 and the antenna switch 407.

On the other hand, a signal transmitted from another person's telephone is received by the antenna 408, and is input to the modulator / demodulator block 405 from the receiver 410 through the antenna switch 407 and the reception filter 409. The modulated or demodulated signal passes through the pulse width modulation / coding block 404 and is output to the speaker 411 as a voice. A controller 412 is provided to control the antenna switch 407, the modulator / demodulator block 405, and the like.
In addition to the above, the controller 412 controls the LCD 401, which is a display unit, the key 402, which is an input unit for numbers, and further the RAM 413, the ROM 414, and the like. In addition, there is a demand for downsizing of the mobile phone 400, and the above-described vibrating piece 20 is used to meet such a demand. Note that the mobile phone 400 includes a temperature-compensated crystal oscillator 415, a receiver synthesizer 416, a transmitter synthesizer 417, and the like as other constituent blocks, but the description thereof is omitted here.

  Moreover, as an electronic apparatus provided with the resonator element 20 of the present invention, a personal computer (mobile personal computer) 500 shown in FIG. The personal computer 500 includes a display unit 501, an input key unit 502, and the like, and the above-described resonator element 20 is used as a reference clock for electrical control.

  In the vibrating piece 20 used in such a cellular phone 400 or personal computer 500, the ratio of the length I of the weight portion 29 to the length L from the base to the tip side of the base portion 21 of the vibrating arm 22 is 35. % To 41%, and the effect of suppressing the frequency sufficiently without increasing the length of the vibrating arm 22 and the thermoelastic loss are reduced, and the Q value can be sufficiently suppressed from decreasing. Effect, and excellent vibration characteristics can be provided. Thereby, the mobile phone 400 and the personal computer 500 can be downsized and highly reliable.

  In addition to the above, the electronic device including the resonator element 20 of the present invention includes, for example, a digital still camera, an ink jet ejection device (for example, an ink jet printer), a laptop personal computer, a television, a video camera, a video tape recorder, a car Navigation devices, pagers, electronic notebooks (including communication functions), electronic dictionaries, calculators, electronic game devices, word processors, workstations, videophones, crime prevention TV monitors, electronic binoculars, POS terminals, medical devices (for example, electronic thermometers, Blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring instruments, instruments (eg, vehicle, aircraft, ship instruments), flight simulator, etc. .

  As mentioned above, although the electronic device of the present invention has been described based on the illustrated embodiment, the present invention is not limited to this, and the configuration of each part is replaced with an arbitrary configuration having the same function. be able to. In addition, any other component may be added to the present invention. For example, in the above-described embodiment, the case where the vibrating piece 20 of the electronic device has the pair of vibrating arms 22 as the vibrating portion has been described as an example, but the number of vibrating arms 22 may be three or more. Further, it may be a beam-type vibrating piece configured by only one vibrating arm having a base portion serving as a fixed end.

  Further, the vibrating arm 22 described in the above embodiment is applied to a gyro sensor or the like in addition to an oscillator such as a voltage controlled crystal oscillator (VCXO), a temperature compensated crystal oscillator (TCXO), a crystal oscillator with a thermostatic chamber (OCXO). Can do.

  And this invention can add a various change in the range which does not deviate from the summary. For example, in the above-described embodiment, the vibration piece 20 in the bending vibration mode that can be provided in the electronic device is taken as an example, and the length ratio of the weight portion 29 according to the present invention is optimally set to provide excellent vibration characteristics. The effect to play was demonstrated. However, the present invention is not limited to this, and even in a vibration piece having a vibration mode other than a bending vibration mode such as a torsional vibration mode and a shear mode, the same effect as that of the above embodiment can be obtained by providing the characteristic configuration of the present invention. it can.

  In the above-described embodiment, the so-called tuning-fork type vibrating piece 20 having the support arm 30 dedicated to the support extending from the base 21 and the two vibrating arms 22 extending in parallel from the base 21 is formed. An embodiment of the present invention has been described. However, the present invention is not limited to this, and the same effect as in the above embodiment can be obtained even with a vibrating piece having no support arm 30.

  In the above-described embodiment, the vibration piece 20 made of a piezoelectric material, in this case, the crystal vibration piece made of quartz has been described. However, the present invention is not limited to this. For example, even a vibrating piece made of silicon or the like that is a non-piezoelectric material can achieve the same effects as in the above embodiment.

  20 ... vibrating piece, 21 ... base, 21a ... first part (base), 21b ... second part (base), 21c ... connection part, 22 ... vibrating arm, 23 ... general part, 24 ... Wide part, 25 ... Jetty part, 26a, 26b ... Long groove, 29 ... Weight part, 30 ... Support arm, 32 ... Bending part, 33, 34 ... Excitation electrode, 95 ... Brazing material, 96 ... Conductive joining member 97, bonding wire, 110, 210 ... package, 111, 211 ... first layer substrate, 112, 212 ... second layer substrate, 112a ... projection, 113, 213 ... third layer substrate, 115, 217 ... vibrating piece Connection terminals 118, 218 ... seal ring, 119, 219 ... lid, 150 ... IC chip as a circuit part, 155 ... electrode pad, 200 ... vibrator, 214 ... fourth layer substrate, 215 ... die pad, 300 ... oscillator, 400 Personal computer as a mobile phone, 500 ... electronic devices as electronic devices.

Claims (6)

A vibrating piece,
A circuit portion electrically connected to the vibrating piece;
Have
The vibrating piece is
The base,
A vibrating arm extending from the base,
The resonating arm is provided with a bottomed long groove having an opening along at least one main surface of both main surfaces of the resonating arm,
The vibrating arm is provided with a weight portion having a width wider than the base side of the vibrating arm on the tip side opposite to the base of the vibrating arm,
The electronic apparatus according to claim 1, wherein a ratio of a length of the weight portion in a length from a base with the base portion to the distal end side in a longitudinal direction of the vibrating arm is in a range of 35% to 41%. The electronic device according to claim 1,
The electronic device according to claim 1, wherein a ratio of the length of the weight portion is in a range of 36% to 40%. The electronic device according to claim 2,
The electronic device according to claim 1, wherein a ratio of the length of the weight portion is in a range of 37% to 39%. In the electronic device as described in any one of Claims 1-3,
The vibrating piece is
The two vibrating arms extended from the base;
A support arm provided extending between the two vibrating arms of the base portion along the longitudinal direction of the vibrating arm;
An electronic device comprising: In the electronic device as described in any one of Claims 1-3,
An electronic apparatus, wherein the base of the vibrating piece and the vibrating arm are made of quartz. In the electronic device as described in any one of Claims 1-3,
An electronic apparatus, wherein the vibration piece is a bending vibration piece exhibiting a bending vibration mode.

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