JP4438165B2 - Piezoelectric oscillator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a piezoelectric oscillator, and in particular, when an adjustment terminal extending from a circuit component constituting an oscillation circuit, a temperature compensation circuit or the like mounted in a package is configured to be adjustable by an operation from the outside of the package, the piezoelectric oscillator The present invention relates to a piezoelectric oscillator that prevents the adjustment terminal from causing various problems when the is mounted on a printed circuit board.
[0002]
[Prior art]
Due to the rapid progress of price reduction and miniaturization with the spread of mobile communication devices such as mobile phones, the price, size and thickness of piezoelectric oscillators such as crystal oscillators used in these communication devices are also reduced. There is a growing demand for conversion. In response to such a demand, not only is a crystal resonator packaged, but an oscillation circuit including a frequency adjustment circuit, a frequency temperature compensation circuit, etc. is integrated and integrated into an IC to reduce the number of components.
6A is a perspective view showing an external structure of a crystal oscillator as an example of a conventional piezoelectric oscillator, FIG. 6B is a cross-sectional view taken along the line AA, and FIG. 6C is a bottom view. The piezoelectric oscillator 1 is mounted on a wiring pattern 7 formed on an upper surface of an insulating substrate 3a constituting an inner bottom surface of a recess 2 on the upper surface of the package body 3 and a lid 4 and a package body 3 by soldering or the like. On the upper surface of the outer frame composed of the crystal resonator 8 and the electronic component 9 formed into an IC package, the side wall 3b constituting the outer frame erected along the four sides of the insulating substrate 3a of the package body 3, and the four side walls 3b And the lid 4 that is fixed and closes the recessed portion 6.
The bottom surface of the insulating substrate 3a is brought into contact with a terminal group 10 such as a power supply terminal, an output terminal, and a ground terminal, as shown in FIG. 6C, and a probe terminal of an adjustment device from the outside of the package body. In addition, an adjustment terminal 11 that receives a signal for adjusting a set value of the electronic component 9 constituting the temperature compensation circuit, the amplifier, and the like via the probe terminal is disposed.
FIG. 7 is an equivalent circuit diagram of the above-described crystal oscillator. The crystal resonator 8 is connected to an oscillation circuit 17 (an electronic component 9 made into an IC) including a temperature compensation circuit 15, an amplifier 16, and the like. The adjustment terminal 11 is led out from the temperature compensation circuit 15 and the amplifier 16 and exposed on the bottom surface of the insulating substrate 3a.
[0003]
The adjustment terminal 11 is an insulating substrate for supplying a signal for adjustment at the adjustment stage after completion of assembly by a crystal oscillator manufacturer in order to adjust the set value of the temperature compensation circuit and the amplification factor of the amplifier. The terminal 3a is exposed at the bottom surface, and is an unnecessary terminal when the assembly maker who purchased the crystal oscillator after completing the adjustment after shipping is mounted on the printed circuit board and used. However, at the stage of mounting the crystal oscillator, the adjustment terminal 11 exposed on the bottom surface of the insulating substrate 3a is simply connected to the land of the printed circuit board surface by soldering the terminal group 10 necessary to make the oscillator function. Therefore, it is necessary to solder and connect the land dedicated for the adjustment terminal provided in advance on the printed circuit board to the adjustment terminal. However, the troublesome work of soldering a large number of adjustment terminals, which are essentially unnecessary for the assembly manufacturer, to the printed circuit board is not only a cause of greatly reducing the workability of mounting electronic components on the printed circuit board. Since the number of wiring patterns on the printed circuit board increases, the result is contrary to the current situation where simplification of pattern routing is strongly required. On the other hand, the presence of such a land dedicated for the adjustment terminal is a cause of hindering the wiring of a useful wiring pattern that can be wired without the adjustment terminal 11.
If it is necessary to readjust the temperature compensation circuit or amplifier after mounting the piezoelectric oscillator on the printed circuit board, the lead terminals have been previously soldered to the adjustment terminals on the bottom of the package. In addition, an adjustment signal is input using this lead terminal. For this reason, the complicated work accompanying mounting of the piezoelectric oscillator has increased, and improvement of this point has been demanded.
[0004]
Therefore, as shown in the sectional view of FIG. 8, a piezoelectric oscillator having a package structure in which adjustment terminals 11 are arranged on the ceiling surface of the recess 12 formed on the bottom surface of the insulating substrate 3a constituting the bottom surface of the insulating package 2. Has been proposed. By arranging the adjustment terminal 11 on the ceiling surface of the recess 12 having a sufficient depth in this way, a sufficient distance from the printed circuit board surface can be secured during mounting. On the printed circuit board, and it is not necessary to solder the two together. However, in order to form a recess having a sufficient depth in the insulating substrate 3a, it is necessary to set the insulating substrate made of a laminated plate of ceramic or the like to a sufficient thickness, which increases the overall height of the package, This is contrary to the demand for lowering the height of electronic components. If the number of laminated ceramic plates constituting the insulating substrate 3a is reduced in order to solve this problem, the total thickness of the insulating substrate 3a is reduced, and the depth of the recess 12 cannot be secured sufficiently. The same problem as in the case of the package 2 having a flat bottom surface as shown in the figure occurs.
Further, when readjustment is performed after the mounting of the piezoelectric oscillator is completed, readjustment is impossible because there is no method of directly contacting the adjustment electrode with the adjustment terminal 11 disposed on the ceiling surface of the recess 12. there were. For this reason, a complicated operation of pulling out the lead terminal from the adjustment terminal 11 and leading it out of the package is necessary.
In this way, piezoelectric oscillators that can realize a low profile that meets the demands for miniaturization and low profile of various devices equipped with a piezoelectric oscillator, and that do not have an adjustment terminal exposed on the bottom, have been proposed so far. Never before. There has also been no piezoelectric oscillator that can be readjusted without connecting the lead terminal to the adjustment terminal after mounting.
[0005]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to form a wall having a sufficient depth for disposing the adjustment terminal on the bottom surface of the insulating substrate constituting the package bottom plate of the piezoelectric oscillator. Piezoelectric oscillator that enables adjustment terminals to be placed in the right place without causing problems when mounting on a printed circuit board, while reducing the overall height of the package by reducing the thickness of the insulation board without increasing the thickness. It is to provide. It is another object of the present invention to provide a piezoelectric oscillator that can be readjusted without connecting a lead terminal to an adjustment terminal after the piezoelectric oscillator is mounted on a printed circuit board.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problems, the invention of claim 1 is directed to a package body including a package body having a recessed portion on the upper surface and a lid for closing the opening of the recessed portion, and a wiring pattern on the inner bottom surface of the recessed portion of the package body. comprising a piezoelectric vibrator mounted, and that electronic components to form an oscillation circuit and a temperature compensation circuit, bottom power terminals exposed disposed in the package body, an output terminal, and a ground terminal, to said piezoelectric vibrators and a piezoelectric oscillator conducting connection between the terminals of the electronic component and the package body lower surface, in which the exposed arranged adjustment terminal of the adjustable the electronic component from the outside in place of the package body, the package The main body is provided with at least one window at an appropriate position on the side wall surrounding the recessed portion, and the adjustment terminal is exposed on the inner bottom surface of the recessed portion exposed from the window. To.
A second aspect of the present invention, an insulating substrate having a wiring pattern on the upper surface, and equipped with an oscillation circuit and a temperature compensation circuit that electronic components make up the on the wiring pattern of the insulating substrate top surface, a bottom surface of the insulating substrate the exposure arrangement the power supply terminal, an output terminal, and includes a ground terminal, and a piezoelectric oscillator conducting connection between the terminals of the electronic component and the insulating substrate bottom surface, externally adjustable in position of the insulating substrate such in that arranged adjustment terminal of the electronic component, the upper surface position of the insulating substrate in upright a plurality of column members having a conductive, for the adjustment to the insulating substrate top surface which is exposed between the pillar member The terminal is exposed and the piezoelectric vibrator is supported by the upper part of each column member.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
FIGS. 1A, 1B, 1C, and 1D are a perspective view, a BB cross-sectional view, a bottom view, and an explanatory view of adjustment work showing a structure of a piezoelectric oscillator as an embodiment of the present invention, The piezoelectric oscillator 21 is a piezoelectric element such as a crystal oscillator mounted by solder or the like on a package 22 formed of a package body 23 and a lid 24 and a wiring pattern 27 formed on an upper surface of an insulating substrate 23a constituting a bottom plate of the package body 23. The vibrator 28 and the electronic component 29 formed into an IC package, the side wall 23b constituting the outer frame standing along the four sides of the insulating substrate 23a of the package body 23, and the upper surface of the outer frame composed of the four side walls 23b are fixed. And the lid 24.
Further, a window 30 for exposing the upper surface of the insulating substrate 23a is formed through at least one side wall 23b. In this example, the window 30 is formed on two opposing side walls 23b.
As shown in FIG. 1C, a terminal group 35 such as a power supply terminal, an output terminal, and a ground terminal is arranged on the bottom surface of the insulating substrate 23a. Further, the adjustment electrode 40 is brought into contact with the outside of the package main body, so that the supply of a signal for adjusting the set value of the electronic component 29 constituting the temperature compensation circuit, the amplifier, etc. is received via the electrode 40. The terminal for use 36 is disposed on the upper surface of the insulating substrate 23 a exposed from the window 30.
When sufficient space for arranging the adjustment terminal 36 cannot be secured on the insulating substrate exposed from the window 30 provided on the two side walls 23b facing each other due to the layout of the wiring pattern on the insulating substrate 23a, etc. As shown by the dotted line, a similar window 30 may be formed on the other side wall, and the remaining adjustment terminals 36 may be arranged in a space on the insulating substrate exposed from the other window 30.
[0008]
As described above, according to the piezoelectric oscillator of the present invention, the through-hole is formed in at least a part of the side wall of the package body so that the upper surface of the insulating substrate 23a communicates with the outside, and the adjustment terminal is placed at a proper position on the upper surface of the insulating substrate. Since it is arranged, by contacting an adjustment electrode (not shown) from the outside of the package body, a signal for adjusting the set value of the electronic component 29 constituting the temperature compensation circuit, the amplifier, etc. is provided via the electrode. Can be supplied. Assembly manufacturers, etc., who have purchased the completed piezoelectric oscillator after completing the adjustment of the set values of the electronic components, need only solder-connect the terminal group 35 on the bottom surface of the package to the land on the printed circuit board, and solder-connect the adjusting terminal 36. Since there is no need to make a connection, not only is the connection work more efficient, but there is no need to provide a special wiring for soldering the adjustment terminal on the printed circuit board, which complicates the wiring on the printed circuit board. Can be prevented. Furthermore, if there is an adjustment terminal on the bottom of the package, it is necessary to place a land dedicated for the adjustment terminal on the surface of the printed circuit board immediately below the adjustment terminal during mounting. However, if the adjustment terminal is not arranged on the bottom surface of the package as in the present embodiment, wiring on the printed circuit board immediately below the bottom surface of the package becomes free.
If there is an adjustment terminal on the bottom of the package as in the past, after mounting the piezoelectric oscillator on the printed circuit board, the adjustment electrode is attached to the adjustment terminal on the bottom of the package for readjustment. It was not easy to input a signal for adjustment by contact. On the other hand, in the present embodiment, the adjustment terminal 36 is exposed on the insulating substrate exposed from the window provided on the side wall of the package body, so that the probe electrode 40 of the adjustment device is mounted even after mounting. Can be inserted into the window 30 and pressed against the adjustment terminal 36 to easily perform the required adjustment work. Note that it is preferable to use a spring material as the probe electrode 40 and supply an adjustment signal while elastically pressing the tip of the probe electrode 40 to the adjustment terminal.
In the above embodiment, the side wall 23b protrudes upward from the insulating substrate 23a side. However, the insulating substrate 23a may be formed in a flat plate shape, while the side wall may protrude downward from the lid 24 side.
[0009]
Next, FIGS. 2A and 2B are a perspective view and a cross-sectional view of a piezoelectric oscillator according to a second embodiment of the present invention. The piezoelectric oscillator 50 has column members 52 at appropriate positions on the upper surface, for example, four corners. A standing insulating substrate 51 is provided, and a bottom portion of a packaged piezoelectric vibrator 53 is fixed on each column member 52. An electronic component 54 including a temperature compensation circuit, an amplifier circuit, and the like is mounted on the wiring pattern on the insulating substrate 51. Each wiring pattern is a connecting conductor (conductive material) wired along the column member 52 or along the outer surface. To the electrode provided on the piezoelectric vibrator 53. Further, an adjustment terminal 55 is exposed at the edge of the insulating substrate 51 exposed in the window 56 formed between the column members 51, and the adjustment electrode is used for adjustment as in the embodiment of FIG. By being in pressure contact with the terminal 55, the set value of the circuit constituting the electronic component 54 can be adjusted. Therefore, it is convenient not only for adjustment at the piezoelectric oscillator manufacturing stage but also for readjustment after mounting on the printed circuit board.
The column member 52 in this example is made of the same material as the insulating substrate 51, and is integrally formed at the same time when the insulating substrate is manufactured. In the case of manufacturing by batch processing, a large-area sheet-like substrate in which a large number of insulating substrates 51 including column members 52 are connected in a planar manner is used, and electronic components are placed on a wiring pattern formed on each region. After mounting, it is divided along the boundary line between the individual areas. Thereafter, the piezoelectric vibrator 53 is fixed on the pillar member 52 on each divided insulating substrate 51 by adhesion or the like.
Also, the piezoelectric vibrator 53 is a package in which a quartz resonator element (not shown) is hermetically accommodated in a package, and a lead portion drawn from an excitation electrode or the like formed on the quartz resonator element is exposed on an outer surface such as a bottom surface of the package. Connected to the external electrode.
FIG. 2 (c) shows a modified example. In this modified example, the insulating substrate 51 is formed in a flat plate shape, and a column member 52 is protruded downward from the piezoelectric vibrator 53 side to insulate each column member 52. The structure fixed to the four corners of the board | substrate 51 is provided. The configuration in which the adjustment terminal 55 is disposed on the upper surface of the insulating substrate exposed from each window 56, the other effects, and the like are the same as those shown in FIGS.
[0010]
Next, FIGS. 3A, 3B, and 3C are modified examples of FIG. 2, and this embodiment is different from the example of FIG. 2 in that the pin member 52 is made of a conductive material such as metal. It is in the configuration using. The column member 52 made of this pin has a structure having a disk and other thin plate portions 52b at the top of the rod-shaped body 52a, and the lower portion of the rod-shaped body 52a is embedded and fixed on the upper surface of the insulating substrate 51. The thin plate portion 52b at the top may be fixed to the metallized electrode 53a on the flat lower surface of the package of the piezoelectric vibrator 53 as in the example of FIG. 3B, or the piezoelectric vibrator 53 as shown in FIG. It may be fixed to the metallized electrode 53a after being fitted in a recess 53b provided in the package. The fixing method is by bonding with a conductive adhesive, solder connection, or the like. The rod-shaped body 52a is electrically connected to the wiring pattern on the insulating substrate 51, and the thin plate portion 52b is electrically and mechanically connected to the electrode 53a provided on the lower surface of the package of the piezoelectric vibrator 53 or the inner surface of the recess 53b. Thereby, it is electrically connected to a lead portion (not shown) in the piezoelectric vibrator 53.
In addition, the said column member 52 uses the thing which plated Ag-Cu on the upper surface of the thin-plate part 53b, for example using Fe-Ni-Co (kovar) as a base material.
The procedure for manufacturing by batch processing is the same as in FIG.
Also in this embodiment, as in the case of FIG. 2, the adjustment terminal 55 is exposed on the upper surface of the insulating substrate 51 exposed in the window formed between the column members 52. Next, the shape of the side wall with window, the insulating substrate provided with the column member, and the piezoelectric vibrator (lid) provided with the column member as in the embodiments of FIGS. 1, 2, and 3 are complicated. Therefore, it takes time to produce each of them, and the productivity is lowered, so the cost is increased. In addition, since the adjustment terminal is arranged on the board that enters inside from the window, it is necessary to make the probe electrode that comes into contact with this special configuration with springiness, and a general pin probe is used. Cannot be adjusted, and the cost required for adjustment increases. In addition, when the special probe is used, contact failure may occur, resulting in a decrease in manufacturing yield.
[0011]
FIGS. 4A and 4B show an embodiment for solving such a problem. The piezoelectric oscillator 60 covers an insulating substrate 61 with an inverted lid 62 and adjusts the outer wall 66 for adjustment. The terminal 70 is exposed. That is, on the upper surface of the insulating substrate 61 positioned in the recess 62 a of the lid 62, the piezoelectric vibrator 63 and the circuit component 64 constituting the oscillation circuit are mounted, while the piezoelectric vibrator 63 and the circuit component 64 are supported. The wiring pattern 65 is connected to the adjustment terminal 70. As shown in FIG. 4B, the adjustment terminal 70 includes a portion 70a exposed to the outer wall 66 and a lead portion 70b introduced into the inside from the joint surface between the insulating substrate 61 and the lid 62. The lead portion 70b Is connected to the wiring pattern 65.
Specifically, the lead portion 70b is a metallized region locked on the insulating substrate or the bottom surface of the lid 62. When the lid is connected on the insulating substrate, the lead portion 70b and the adjustment terminal 70 are electrically connected. Connect to.
In this example, the exposed portion 70a of the adjustment terminal 70 is extended from the outer wall surface of the lid 62 to the side surface of the insulating substrate 61. However, this is only an example, and only the outer wall surface of the lid or the side surface of the insulating substrate 61 is provided. Each of the exposed portions 70a may be disposed only in each case.
According to this embodiment, since it is not necessary to form a window or the like of the lid 62, the manufacturing cost can be reduced, and the adjustment terminal 70 is merely formed on the flat outer wall 66. A probe can be used, and the cost required for adjustment can be reduced. Furthermore, since the area of the adjustment terminal can be increased, workability can be improved using a thick probe.
In place of the lid 62 shown in FIG. 4, a piezoelectric vibrator that also serves as the lid 62 may be used. That is, the lid itself may be configured as a piezoelectric vibrator as in the embodiment of FIGS.
Next, FIGS. 5A and 5B are a modified embodiment of FIG. 4, and are a perspective view and a cross-sectional view when a lid is also used as a piezoelectric vibrator. A piezoelectric vibrator 80 also serving as a lid is fixed on the insulating substrate 61 of the piezoelectric oscillator 60. An adjustment terminal 70 is formed on the outer wall of the piezoelectric vibrator 80. The adjustment terminal 70 includes a portion 70 a exposed on the outer wall and a lead portion 70 b introduced into the inside from the joint surface between the insulating substrate 61 and the piezoelectric vibrator 80, and connects the lead portion 70 b to the wiring pattern 65.
Next, as shown in FIG. 5B, the piezoelectric vibrator 80 seals the space including the circuit component 64 on the insulating substrate by the package 81 having an H-shaped section and the lower recess 82 of the package 81. A piezoelectric vibration element 84 such as a crystal vibration element is accommodated in the upper recess 83 and the upper recess 83 is hermetically sealed with a metal lid 85.
Also in this embodiment, since it is not necessary to form a window or the like on the side wall, the manufacturing cost can be reduced, and the adjustment terminal 70 is only formed on a flat outer wall, so a general pin probe is used. The cost required for adjustment can be reduced. Furthermore, since the area of the adjustment terminal can be increased, workability can be improved using a thick probe.
[0012]
【The invention's effect】
As described above, according to the present invention, in order to form a recess having a sufficient depth for disposing the adjustment terminal on the bottom surface of the insulating substrate constituting the package bottom plate of the piezoelectric oscillator, Without adjusting the overall height by increasing the thickness, and by reducing the overall height of the package by reducing the thickness of the insulating substrate, the adjustment terminals are placed in the appropriate places where problems do not occur when mounted on a printed circuit board. can do. In other words, when the adjustment terminal is placed on the bottom surface of the insulating substrate, it is necessary to connect the adjustment terminal to the dedicated land on the printed circuit board, or the adjustment terminal is used for readjustment after mounting. However, in the present invention, the adjustment terminal is arranged on the inner bottom surface (upper surface of the insulating substrate) of the package body exposed from the window provided on the side wall of the package body. It is not necessary to connect an adjustment terminal after mounting on a printed circuit board, and readjustment work after mounting is easy.
Further, since the adjustment terminal is formed on the outer surface of the side wall of the piezoelectric oscillator, it is not necessary to form a window or the like on the side wall, and the manufacturing cost can be reduced. Moreover, since the adjustment terminal is only formed on the flat outer wall, a general pin probe can be used, and the cost required for adjustment can be reduced. Furthermore, since the area of the adjustment terminal can be increased, workability can be improved using a thick probe.
[Brief description of the drawings]
FIGS. 1A, 1B, 1C, and 1D are a perspective view, a BB cross-sectional view, a bottom view, and an explanatory view of adjustment work showing a structure of a piezoelectric oscillator as an embodiment of the present invention.
FIGS. 2A and 2B are a perspective view and a sectional view of a piezoelectric oscillator according to another embodiment of the present invention, and FIG. 2C is a perspective view showing a modified example thereof.
FIGS. 3A, 3B and 3C are explanatory views of a piezoelectric oscillator according to another embodiment of the present invention. FIGS.
FIGS. 4A and 4B are a perspective view and a cross-sectional view showing a configuration of a piezoelectric oscillator according to another embodiment of the present invention.
FIGS. 5A and 5B are a perspective view and a cross-sectional view showing a configuration of a piezoelectric oscillator according to another embodiment of the present invention.
6A, 6B, and 6C are explanatory views of a conventional piezoelectric oscillator.
FIG. 7 is an equivalent circuit diagram of a conventional piezoelectric oscillator.
FIG. 8 is a sectional view showing the configuration of another conventional piezoelectric oscillator.
[Explanation of symbols]
21 piezoelectric oscillator, 22 insulating package, 23 package body, 23a insulating substrate, 23b side wall, 24 lid, 27 wiring pattern, 28 crystal oscillator, 29 electronic component, 30 window, 35 power supply terminal, output terminal, ground terminal, etc. Terminal group, 36 adjustment terminal, 40 electrode, 50 piezoelectric oscillator, 52 column member, 52a rod-shaped body, 52b thin plate portion, 53 piezoelectric vibrator, 54 electronic component, 60 piezoelectric oscillator, 61 insulating substrate, 62 lid, 62a recess , 63 Piezoelectric vibrator, 64 circuit parts, 65 wiring pattern, 70 adjustment terminal, 70a exposed part, 70b lead part

Claims (2)

A package body having a recess on the upper surface, a package having a lid for closing the opening of the recess, a piezoelectric vibrator mounted on a wiring pattern on the inner bottom surface of the recess , an oscillation circuit, and a temperature compensation circuit and to that electronic components constituting a power supply terminal exposed disposed on the bottom surface of the package body, an output terminal, and includes a ground terminal, and the piezoelectric vibrator and the respective terminals of the electronic component and the package body lower surface a piezoelectric oscillator conducting connection, in which the exposed arranged adjustment terminal of the adjustable the electronic component from the outside in place of the package body, the package body, at least one in place of the side wall surrounding the recess A piezoelectric oscillator comprising: two windows, wherein the adjustment terminals are exposed on the bottom surface of the recessed portion exposed from the windows. An insulating substrate having a wiring pattern on the top surface, the insulating and oscillation circuit and that electronic components make up the temperature compensation circuit is mounted on the upper surface of the substrate of the wiring pattern on the power supply terminals exposed disposed on the bottom surface of the insulating substrate, output terminals, and includes a ground terminal, and a piezoelectric oscillator conducting connection between the terminals of the electronic component and the insulating substrate bottom surface, for adjusting the adjustable the electronic component from the outside in place of the insulating substrate in those places the terminals, erected a plurality of column members having a conductive on the upper surface position of the insulating substrate, the adjustment terminal exposed disposed in the insulating upper surface of the substrate exposed between the pillar member, the A piezoelectric oscillator characterized in that a piezoelectric vibrator is supported by the upper part of each column member.

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