JP2015207867A - Oscillator device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-precision and stable oscillation source that can shield foreign radiation noise or low-frequency magnetic noise and also shield even noise infiltrating through a power supply circuit.SOLUTION: An oscillator device has a cap-shaped metal cover 6 which covers an SMD type oscillator 4 having plural terminals mounted on a principal surface of a print board 1 and a capacitor 5. The oscillator is mounted on the surface of the principal face of the print board, and has castellations 9c, 9d forming plural side surface electrodes 10c, 10d connected to terminal pads on the side wall of the print board. The capacitor 5 is inserted between the power supply terminal of the oscillator and the ground terminal. SMD-mounted mount terminals 11a, 11c, 11d are provided to the back surface of the print board. The oscillator 4 shields foreign radiation noise in four directions parallel to the board face of the print board 1 by the cap-shaped metal cover or in a vertical direction to the print board 1 by the metal cover 4b of the oscillator itself and the cap-shaped metal cover 6, and reduces foreign noise infiltrating through the power supply terminal by the capacitor 5.

Description

  The present invention relates to an oscillator device, and more particularly to an oscillator device provided with a shield cover that shields a surface-mounted oscillator from external radiation noise on a printed board on which the surface-mounted oscillator is mounted.

  2. Description of the Related Art An oscillator device is known in which a surface mount type (SMD) oscillator is mounted on a printed circuit board, and the mounted piezoelectric oscillator is covered with a shield that shields external radiation noise. In this type of oscillator device, an oscillator having an oscillator and an oscillation circuit chip (IC chip) contained in a container is mounted on a printed circuit board, and a cover made of a metal material that shields the mounted oscillator from external radiation noise (metal cover, shield) A structure covered with a cover) is generally used.

  Note that printed circuit boards are not limited to those equipped only with an oscillator, but may be equipped with electronic components such as resistors and capacitors necessary for the oscillator device and IC chips separate from the oscillation circuit chip together with the oscillator. Here, a structure in which only an oscillator in which an oscillator and an IC chip in which a circuit constituting an oscillation circuit is integrated with the oscillator is integrated is mounted on a printed board will be described. In the following description, it is assumed that a general crystal resonator is used as the vibrator. However, the present invention is a vibrator using a piezoelectric material other than quartz, and a silicon / MEMS vibration using semiconductor processing technology. The same applies to an oscillator device equipped with a child.

  Oscillator devices are widely used in various portable devices. A typical crystal oscillator device is widely used as a reference source for operating frequency and time. Here, a crystal oscillator device as a specific example for explaining the present invention includes a crystal oscillator and a crystal oscillator in which an IC chip in which an oscillation circuit constituting the oscillator is integrated with the crystal oscillator is sealed in a container, or such Electronic components that constitute a filter body circuit such as a crystal oscillator and a temperature control circuit are mounted on a common printed circuit board.

  FIG. 7 is a perspective view illustrating a configuration example of a conventional oscillator device with a part broken away. FIG. 8 is a plan view for explaining a main surface (oscillator mounting surface) of a printed circuit board made of a ceramic (also referred to as a green sheet) single plate or multilayer plate constituting the oscillator device shown in FIG. The oscillator 4 mounted on the printed circuit board 1 stores a crystal resonator in a concave portion of a container body 4a formed of an insulating sheet suitable for a green sheet, and the concave portion is covered and sealed with a metal cover 4b. The metal cover 4b is fixed to the container body 4a with a metal ring 4c interposed between the opening end of the recess of the container body 4a.

  And the terminal (mounting terminal, not shown) for mounting in the printed circuit board 1 is provided in the surface on the opposite side to the said metal cover 4b of the container main body 4a. With the progress of miniaturization, a so-called surface mount type (SMD) is often used as the mounting terminal. Note that an IC chip or the like in which an oscillation circuit that constitutes an oscillator together with a crystal resonator is integrated is mounted in a concave portion in which the crystal resonator is sealed, or is mounted on another portion of the container body.

  The oscillator 4 is mounted on the main surface of the printed circuit board 1 by SMD. As shown in FIG. 8, a required wiring pattern 2 including electrode pads is printed on the main surface of a printed board 1 having a rectangular shape (here, a rectangular shape). The pair of side walls (here, the side walls on the long side) of the printed board 1 have castellations 9 (9a to 9d), and side electrodes 10 (10a to 10d) are formed on the castellations. In FIG. 8, a power supply terminal (VDD), an output terminal (OUTPUT), a ground terminal (GND), and a control terminal (Vcont or Stand-By) are assigned to each of the side electrodes 10a to 10d.

  A plurality of terminal pads 15 (15a to 15d) corresponding to the mounting terminals of the oscillator are provided in the oscillator mounting region 3 in the central portion of the main surface of the printed circuit board 1, each of which is a wiring pattern 2 and a side electrode 10 of the castellation. (10a to 10d). One of the side electrodes 10 (10a to 10d) (the side electrode 10c in FIGS. 7 and 8) is assigned to the ground terminal (GND).

  On the main surface of the printed circuit board 1, cover fixing electrodes 2a and 2b are provided on the short side. One cover fixing electrode 2b is connected to a ground electrode 8 disposed across the oscillator mounting region 3. The ground electrode 8 is located immediately below the mounted oscillator 4 and acts to shield electromagnetic radiation from the mounted oscillator and to protect the oscillator from external radiation action electromagnetic waves.

  The oscillator 4 has a metal cover 4b. The crystal cover and the electronic components that also incorporate the metal cover 4b protect the oscillator from external radiated electromagnetic waves and shield the electromagnetic radiation from itself.

  A cap-shaped metal cover 6 is provided so as to cover the main surface of the printed circuit board 1 on which the oscillator 4 is mounted. The metal cover 6 is formed with an open portion on one side, and the open portion is covered with the main surface of the printed circuit board, and the open edge on the short side is fixed to the cover fixing electrodes 2 a and 2 b with solder 7. The oscillator 4 is built in a housing formed by the printed circuit board 1 and the cap-shaped metal cover 6. The installation position of the cap-shaped metal cover 6 is such that a positioning protrusion 18 (18a to 18d, 18b and 18c is not shown) provided at the open end is a cover positioning recess 17 (17a to 17a) formed on the main surface of the printed circuit board 1. 17d). The cap-shaped metal cover 6 is connected to the side electrode 10c connected to the mounting terminal grounded (GND) through one cover fixing electrode 2b, the terminal pad 15c, and the wiring pattern 2.

  On the back surface (the surface opposite to the main surface) of the printed circuit board 1, SMD type mounting terminals 11 (11a to 11d, 11c are not shown) to be mounted on a predetermined printed circuit board of an applicable device are provided. The mounting terminal 11 is connected to the side electrode 10.

  The oscillator device shown in FIG. 7 has a shield structure in which a built-in oscillator 4 is surrounded by a cap-shaped metal cover 6 and a ground electrode 8 disposed on the main surface of the printed circuit board 1 immediately below the oscillator. The oscillator 4 and the cap-shaped metal cover 6 are arranged at a distance d1 with respect to the ceiling of the metal cover 6, distances d2 and d4 with respect to the long side wall, and distances d3 and d5 with respect to the short side wall. Yes.

  Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4 can be cited as those that disclose conventional techniques related to the oscillator device according to the present invention. Patent Document 1 discloses a crystal oscillator in which a wiring board (printed board) on which electronic components such as a CAN package type (or lead type) crystal resonator and a chip capacitor are mounted is sealed in a brass case.

  Patent Document 2 shields a crystal oscillator from low-frequency magnetic noise and high-frequency electromagnetic fields by covering a wiring board that is an oscillator with a piezoelectric vibrator and electronic components mounted thereon with an iron-based case and an aluminum case. A piezoelectric device is disclosed. Patent Document 3 is an oscillator in which a printed circuit board on which an SMD type piezoelectric vibrator sealed with a metal lid and an electronic component is mounted is further covered with a metal case, and a tongue provided on the side surfaces of a pair of sides of the metal case. Disclosed is a piezoelectric oscillator structure in which a shape portion is soldered to a piezoelectric vibrator. Patent Document 4 also discloses a crystal oscillator in which legs formed on an outer metal cover are fitted to side electrodes of a printed board when the metal cover is attached to the printed board.

Japanese Patent Laid-Open No. 11-68465 JP 2010-56767 A Japanese Patent Laid-Open No. 2001-53547 Japanese Patent Laid-Open No. 10-154663

  As disclosed in the above-mentioned prior art documents, in addition to the shielding effect by the metal cover of the oscillator itself, a structure for shielding the oscillator double by providing a shield cover for electromagnetic noise on the printed circuit board on which the oscillator is mounted, and In this case, it is possible to shield external radiation electromagnetic waves or low-frequency magnetic noise. However, it is difficult to block noise entering through the power line. Noise that enters through the power supply line (power supply noise) causes fluctuations in the oscillation frequency, and is one of the problems to be solved in realizing a high-definition and stable oscillation source.

An object of the present invention is to provide an oscillator device capable of obtaining a high-definition and stable oscillation source by shielding external radiation noise and low-frequency magnetic noise with respect to an oscillator and also blocking noise entering through a power supply circuit. It is to provide.

To achieve the above object, the present invention is mounted on a main surface of a printed circuit board, an oscillator and an electronic component having a plurality of surface-mounting terminals mounted on the main surface of the printed circuit board, and the printed circuit board. An oscillator device comprising a cap-shaped metal cover provided to cover the oscillator and the electronic component,
The oscillator has a vibrator / or a container main body having a recess for accommodating the vibrator and an electronic component, and a metal cover for covering the opening of the recess and sealing the vibrator / or the vibrator and the electronic component. And a plurality of terminals including at least a power supply terminal, an oscillation output terminal, a ground terminal, and a control terminal on the surface opposite to the metal cover of the container body,
The main surface of the printed circuit board on which the oscillator is mounted is formed with a wiring pattern in which a plurality of terminal pads corresponding to the plurality of terminals of the oscillator are formed, and a cover fixing electrode connected to the ground terminal,
A side wall of the printed board has a castellation in which side electrodes connected to the plurality of terminal pads are formed,
A capacitor is inserted between the side electrode corresponding to the power supply terminal and the ground terminal,
A cap-shaped metal cover provided to cover the oscillator and electronic components mounted on the main surface is soldered to the cover fixing electrode,
On the back surface, which is the opposite surface of the main surface of the printed circuit board, a mounting terminal for connecting to the side electrode and SMD mounting on an applied electronic device is provided,
The oscillator shields external radiation noise by the cap-shaped metal cover in four directions parallel to the substrate surface of the printed circuit board, and by the metal cover and the cap-shaped metal cover of the oscillator itself in the direction perpendicular to the printed circuit board. The external noise entering through the power supply terminal is blocked by the capacitor.

Further, according to the present invention, the printed circuit board is formed of a multi-layered green sheet, and on the back side of the upper layer sheet constituting the main surface, most of the mounting area of the oscillator and the electronic component and the wiring pattern forming area Comprising a ground electrode connected to the ground terminal, and having a spread corresponding to a region including
The oscillator has a direction parallel to the substrate surface of the printed circuit board by the cap-shaped metal cover, and in a direction perpendicular to the printed circuit board, by the metal cover of the oscillator itself and the cap-shaped metal cover, and further by the ground electrode, The external radiation noise is shielded, and the external noise entering through the power supply terminal is blocked by the capacitor.

In the present invention, the printed circuit board is laminated so that the middle layer sheet and the lower layer sheet are in this order on the side opposite to the main surface of the upper layer sheet,
On the back surface opposite to the main surface of the lower layer sheet, a mounting terminal for connecting to the side electrode and SMD mounting on an applied electronic device is provided,
The ground electrode is provided on either the surface facing the upper layer sheet of the middle layer sheet or the surface facing the lower layer sheet,
A direction parallel to the substrate surface of the printed circuit board is provided by the cap-shaped metal cover, and in a direction perpendicular to the printed circuit board, the metal cover of the oscillator itself and the cap-shaped metal cover are provided. Radiation noise is shielded, and external noise entering through the power supply terminal is blocked by the capacitor.

In the present invention, the printed circuit board has a two-layer multilayer structure in which a lower layer sheet is laminated on the surface opposite to the main surface of the upper layer sheet,
On the back surface, which is the opposite surface of the main surface of the lower layer sheet, is connected to the side electrode and provided with a mounting terminal for SMD mounting on an applied electronic device,
The ground electrode is provided on the surface of the lower sheet facing the upper sheet,
The oscillator is configured by the cap-shaped metal cover in a direction parallel to the substrate surface of the printed circuit board, by the metal cover of the oscillator itself and the cap-shaped metal cover in a direction perpendicular to the printed circuit board, and further by the ground electrode. The external radiation noise is shielded, and the external noise entering through the power supply terminal is blocked by the capacitor.

  The present invention is not limited to the above-described configuration, and various modifications can be made without departing from the technical idea of the present invention.

  According to the present invention, the influence of external radiation noise on the oscillator mounted on the printed circuit board is shielded with high efficiency, and noise that enters through the power supply line is prevented by connecting a capacitor between the power supply terminal and the ground terminal. It is interrupted and a high-definition oscillation output can be obtained. Also, the printed circuit board is composed of a multilayer sheet, and the ground electrode is provided with an interval corresponding to the thickness of at least one sheet constituting the printed circuit board side of the oscillator mounted on the main surface of the printed circuit board. As a result, the stray capacitance is reduced, and the dullness of the oscillation waveform caused by this stray capacitance can be proposed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a part broken away and illustrating an embodiment of an oscillator device according to the present invention. FIG. 2 is a developed perspective view illustrating the configuration of the printed circuit board according to the first embodiment of the present invention configured by the multilayer green sheet in FIG. 1. It is the top view and side view explaining the main surface of the printed circuit board in FIG. It is a top view explaining the mounting surface of the printed circuit board in FIG. 1A is a plan view illustrating a printed circuit board in FIG. 1 for explaining an embodiment 2 of the oscillator device according to the present invention, and FIG. FIG. 6 is a developed perspective view of a printed circuit board for explaining a configuration of a second embodiment of the present invention configured by the multilayer green sheet in FIG. 5. It is a perspective view which fractures | ruptures a part explaining the structural example of the conventional oscillator apparatus, and shows an inside. It is a top view explaining the main surface of the printed circuit board which consists of a ceramic single board or multilayer board which comprises the oscillator apparatus shown in FIG.

  Hereinafter, embodiments of an oscillator device according to the present invention will be described in detail with reference to FIGS. 1 to 4.

  FIG. 1 is a perspective view showing a part of the oscillator device according to the embodiment of the present invention, with a part thereof broken away. FIG. 2 is an exploded perspective view for explaining the configuration of the first embodiment of the present invention, which is formed of a multilayer green sheet as the printed board in FIG. 3A is a plan view illustrating the printed circuit board in FIG. 1, and FIG. 3B is a side view of FIG. 3A viewed from the direction of arrow A. FIG. FIG. 4 is a plan view for explaining a mounting surface of the printed board in FIG. In FIG. 1, an oscillator 4 mounted on a printed circuit board 1 has a crystal resonator (not shown) in a recess of a container body 4a formed of an insulating sheet suitable for a green sheet, similar to that described in FIG. The recess is covered with a metal cover 4b and sealed. The metal cover 4b is fixed to the container body 4a with a metal ring 4c interposed between the opening of the recess of the container body 4a.

  A terminal for mounting the oscillator 4 on the printed circuit board 1 is provided on the surface of the container body 4a opposite to the metal cover 4b. With the progress of miniaturization, a so-called surface mount type (SMD) is often used as the mounting terminal. Note that an IC chip or the like in which an oscillation circuit that constitutes an oscillator together with a crystal resonator is integrated is mounted in a recess in which the crystal resonator is sealed, or is mounted on another portion of the container body (not shown). ).

  The oscillator 4 is mounted on the main surface of the printed circuit board 1 by SMD. As described with reference to FIG. 8, a required wiring pattern 2 including electrode pads is printed on the main surface of the printed board 1 having a rectangular shape (in this case, a rectangular shape). The pair of side walls (here, the side walls on the long side) of the printed circuit board 1 has castellations 9 (9a, 9b, 9c, 9d), and side electrodes 10 (10a, 10b, 10c, 10d) is formed. As shown in FIG. 3, each of the side electrodes 10a, 10b, 10c, and 10d has a power supply terminal (VDD), an output terminal (OUTPUT), a ground terminal (GND), and a control terminal (Vcont or Stand-By). Each is assigned.

  A plurality of terminal pads 15 (15a, 15b, 15c, 15d) corresponding to the mounting terminals of the oscillator are provided in the oscillator mounting region 3 in the central portion of the main surface of the printed circuit board 1 shown in FIG. The pattern 2 is connected to the side electrode 10 (10a, 10b, 10c, 10d) of the castellation. One of the side electrodes 10a, 10b, 10c, and 10d (in this embodiment, the side electrode 10c) is assigned to the ground terminal (GND). On the main surface of the printed circuit board 1, cover fixing electrodes 2a and 2b are provided on the short side. One cover fixing electrode 2a is free from the wiring pattern, and the other cover fixing electrode 2b is connected to the side electrode 10c which is a ground electrode terminal.

  In this embodiment, the printed circuit board 1 has a three-layer multilayer structure of three green sheets (upper layer sheet 1a, middle layer sheet 1b, and lower layer sheet 1c). The wiring pattern 4 and the like described above are formed on the main surface of the upper layer sheet 1a, and the oscillator 4 is mounted. On the main surface of the intermediate layer sheet 1b (surface facing the upper layer sheet 1a), there is an area corresponding to a region including most of the mounting region of the electronic components such as the oscillator 4 and the capacitor 5 and the region where the wiring pattern 2 is formed. The ground electrode 8 is solid. The ground electrode 8 is connected to the side electrode 10c and grounded. In addition, you may form the ground electrode 8 in the other main surface (surface which opposes the lower layer sheet 1c) of the intermediate | middle layer sheet | seat 1b. The capacitor 5 is inserted between the power supply terminal of the oscillator 4 and the side electrode 10c connected to the ground terminal.

  A multi-layer printed circuit board 1 on which electronic components such as an oscillator 4 and a capacitor 5 are mounted is provided with a cap-shaped metal cover 6. The cap-shaped metal cover 6 is processed into a cap shape having an opening using a metal plate, and a positioning projection 18 (18a, 18b, 18c, 18d, 18d is not shown) is formed on a part of the opening side. It is. On the other hand, cover positioning recesses 17 (17a, 17b, 17c, 17d) are formed at positions corresponding to the positioning protrusions 18a, 18b, 18c, 18d of the upper layer sheet 1a of the printed circuit board 1. Then, the positioning protrusions 18a, 18b, 18c and 18d of the metal cover 6 are aligned with the cover positioning recesses 17a, 17b, 17c and 17d of the printed circuit board 1, and the short sides are soldered to the cover fixing electrodes 2a and 2b with solder 7. It is fixed.

  In this embodiment, the cover positioning recess 17 is formed only on the upper layer sheet 1 a of the printed circuit board 1, and the positioning protrusion 18 is provided with a length that matches the depth of the recess 17. However, the cover positioning recess 17 is formed to have a depth that penetrates the upper layer sheet 1a of the printed circuit board 1 and reaches the middle layer sheet 1b, or a depth that is dug into the middle layer sheet 1b. The positioning protrusion 18 may be provided with a matching length. The side electrodes 10a, 10b, 10c, and 10d of the upper layer sheet 1a, the middle layer sheet 1b, and the lower layer sheet 1c are electrically integrated in the castellations 9a, 9b, 9c, and 9d, respectively. 11b, 11c, 11d.

  In the oscillator device according to the present embodiment configured as described above, the size of the oscillator 4 at that time is smaller than that of the oscillator mounted on the conventional oscillator device described with reference to FIGS. In FIG. 7, the oscillator 4 and the cap-shaped metal cover 6 are at a distance d1 with respect to the ceiling of the metal cover 6, distances d2 and d4 with respect to the long side wall, and distances d3 and d5 with respect to the short side wall. Has been placed.

  A cap-shaped metal cover 6 is provided so as to cover the main surface of the printed circuit board 1 on which the oscillator 4 is mounted. The cap-shaped metal cover 6 has a cap shape, and its open portion is covered with the main surface of the printed circuit board, and the short side open edge is fixed to the cover fixing electrodes 2a and 2b with solder 7. The oscillator 4 is built in a housing formed by the printed circuit board 1 and the cap-shaped metal cover 6. The ground contact position of the cap-shaped metal cover 6 is such that the positioning protrusions 18 (18a to 18d, 18b and 18c are not shown) provided at the open end are covered positioning recesses 17 (17a to 17a) formed on the main surface of the printed circuit board 1. 17d). The cap-shaped metal cover 6 is connected to the side electrode 10c connected to the mounting terminal grounded (GND) through one cover fixing electrode 2b, the terminal pad 15c, and the wiring pattern 2.

  As shown in FIG. 4, SMD type mounting terminals 11 (11 a, 11 b, 11 c, 11 d) to be mounted on a predetermined printed circuit board of an applicable device are provided on the back surface (the surface opposite to the main surface) of the printed circuit board 1. It has been. The mounting terminals 11 (11a, 11b, 11c, 11d) are connected to the side electrodes 10 (10a, 10b, 10c, 10d), respectively.

  The conventional oscillator device shown in FIG. 7 has a shield structure in which a built-in oscillator 4 is surrounded by a cap-shaped metal cover 6 and a ground electrode 8 disposed on the main surface of the printed circuit board 1 immediately below the oscillator. is there. The oscillator 4 and the cap-shaped metal cover are arranged at a distance d1 with respect to the ceiling of the cap-shaped metal cover, distances d2 and d4 with respect to the long side wall, and distances d3 and d5 with respect to the short side wall. Yes. On the other hand, in this embodiment, the printed circuit board 1 and the cap-shaped metal cover 6 of the conventional size are used, and the height is lower than that of the conventional oscillator and the size in plan view is small. The oscillator 4 and the cap-shaped metal cover 6 have a distance D1 (D1> d1) with respect to the ceiling of the metal cover 6, and distances D2 (D2> d2), D4 (D4> d4) with respect to the long side wall, They are arranged at distances D3 (D3> d3) and D5 (D5> d5) with respect to the short side wall. A comparison of specific numerical values is as follows.

  For example, when the plan view size of the printed circuit board 1 specified by a customer or the like is 13.8 mm × 9.2 mm and the height of the cap-shaped metal cover 6 is the same, the plan view size of the conventional oscillator 4 is 7.0 mm. Although it is × 5.0 mm, the size in plan view of the oscillator 4 of this embodiment is 2.5 mm × 2.0 mm. The distance between the metal cover of the oscillator itself and the ceiling of the cap-shaped metal cover 6 is about two to three times that of the conventional one, and the area occupied by the oscillator on the printed circuit board is a fraction. In the present embodiment, the distance from the oscillator 4 to the inner wall or ceiling of the cap-shaped metal cover 6 is longer than that in the prior art. Thereby, external radiation noise is significantly reduced.

  The ground electrode 8 provided on the printed circuit board 1 provides a shielding structure for the oscillator 4 mounted on the main surface on the back surface (the surface opposite to the cap-shaped metal cover). The ground electrode 8 is not provided on the main surface of the printed circuit board 1 as described with reference to FIG. 8 (that is, in the vicinity of the back surface of the oscillator 4), but at least the thickness of the upper layer sheet 1a constituting the printed circuit board 1. Only the minute is isolated from the oscillator 4. Accordingly, the stray capacitance formed between the ground electrode 8 and the oscillator 4 and the wiring pattern 2 becomes small, and the oscillation waveform dullness due to the stray capacitance can be suppressed.

  According to the present embodiment, it is possible to shield external radiation noise and reduce external noise entering through the power supply terminal by the capacitor to obtain a high-definition oscillation output. In addition, by providing a ground electrode through at least one layer of the printed circuit board, the stray capacitance between the oscillator, electronic components, and wiring pattern mounted on the main surface is reduced, and distortion such as dullness is generated in the oscillation waveform. It can be avoided.

  5A is a plan view of the printed circuit board in FIG. 1 for explaining an embodiment 2 of the oscillator device according to the present invention, and FIG. 5B is a side view of FIG. FIG. 6 is an exploded perspective view of a printed circuit board for explaining the configuration of the second embodiment of the present invention configured by the multilayer green sheet in FIG. In this example, as shown in FIG. 5B, the printed circuit board 1 was composed of two green sheet upper layer sheets 1a and lower layer sheets 1c.

  An oscillator 4 and a capacitor 5 are mounted on the main surface of the upper layer sheet 1a, and a wiring pattern 2 and the like are formed. Since the configuration of this main surface is the same as that of the first embodiment, redundant description will not be given.

  The present embodiment is the same as the first embodiment except that the printed circuit board 1 is a multilayer printed circuit board composed of two sheets of an upper layer sheet 1a and a lower layer sheet 1c. In the second embodiment, as shown in FIG. 6, the same wiring pattern 2 and cover fixing electrodes 2a and 2b as those of the first embodiment are formed on the main surface of the upper sheet 1a, and the oscillator 4 and the capacitor 5 are mounted. . The capacitor 5 is inserted into the side electrode 10c that becomes the power supply terminal and the ground terminal of the oscillator 4.

  The main surface of the lower layer sheet 1c of the printed circuit board 1 (the surface facing the upper layer sheet 1a) is a region including most of the mounting region of the electronic components such as the oscillator 4 and the capacitor 5 and the region where the wiring pattern 2 is formed. The ground electrode 8 having a corresponding spread is solid. The ground electrode 8 is connected to the side electrode 10c and grounded. In addition, you may form the ground electrode 8 in the other main surface (surface which opposes the lower layer sheet 1c) of the upper layer sheet 1a. On the back surface (the surface opposite to the main surface) of the lower layer sheet 1c, SMD type mounting terminals 11 (11a to 11d, 11c) to be mounted on a predetermined printed circuit board of an applicable device are provided.

  The side surface electrodes 10a, 10b, 10c, and 10d of the upper layer sheet 1a and the lower layer sheet 1c are electrically integrated in the castellations 9a, 9b, 9c, and 9d, and are respectively mounted on the mounting terminals 11a, 11b, 11c, 11d.

  The ground electrode 8 provided on the lower layer sheet 1c gives a shielding structure to the back surface (the surface opposite to the cap-shaped metal cover 6) of the oscillator 4 mounted on the main surface of the upper layer sheet 1a. The ground electrode 8 is not provided on the main surface of the printed circuit board 1 as described with reference to FIG. 8 (that is, in the vicinity of the back surface of the oscillator 4), but at least the thickness of the upper layer sheet 1a constituting the printed circuit board 1. Only the minute is isolated from the oscillator 4. Therefore, the stray capacitance formed between the ground electrode 8 and the oscillator 4 and the wiring pattern 2 is reduced. Dullness of the oscillation waveform due to stray capacitance can be suppressed.

  According to the present embodiment, it is possible to shield external radiation noise and reduce external noise entering through the power supply terminal by the capacitor to obtain a high-definition oscillation output. In addition, by providing the ground electrode through at least one layer of the printed circuit board, the stray capacitance between the oscillator and electronic components mounted on the main surface or the wiring pattern is reduced, and distortion such as dullness is generated in the oscillation waveform. It can be avoided.

  The present invention is not limited to the oscillator device using the above-described crystal oscillator, but can be similarly applied to other piezoelectric oscillators, MEMS oscillators, other crystal devices, and similar electronic components.

  DESCRIPTION OF SYMBOLS 1 ... Printed circuit board, 1a ... Upper layer sheet, 1b ... Middle layer sheet, 1c ... Lower layer sheet, 2 ... Wiring pattern, 2a, 2b ... Cover fixed electrode, 3 ... Oscillator Mounting position, 4 ... oscillator, 5 ... capacitor, 6 ... cap metal cover, 7 ... solder, 8 ... installation electrode, 9 ... castellation, 10 ... side electrode , 11 ... mounting terminals, 15 ... terminal pads, 17 ... cover positioning recesses, 18 ... positioning protrusions.

Claims (4)

A printed circuit board, an oscillator and an electronic component having a plurality of surface-mounted terminals mounted on the main surface of the printed circuit board, and the oscillator and the electronic component mounted on the main surface of the printed circuit board are provided. An oscillator device comprising a cap-shaped metal cover,
The oscillator has a vibrator / or a container main body having a recess for accommodating the vibrator and an electronic component, and a metal cover for covering the opening of the recess and sealing the vibrator / or the vibrator and the electronic component. And a plurality of terminals including at least a power supply terminal, an oscillation output terminal, a ground terminal, and a control terminal on the surface opposite to the metal cover of the container body,
The main surface of the printed circuit board on which the oscillator is mounted is formed with a wiring pattern in which a plurality of terminal pads corresponding to the plurality of terminals of the oscillator are formed, and a cover fixing electrode connected to the ground terminal,
A side wall of the printed board has a castellation in which side electrodes connected to the plurality of terminal pads are formed,
A capacitor is inserted between the side electrode corresponding to the power supply terminal and the power supply terminal of the oscillator,
A cap-shaped metal cover provided to cover the oscillator and electronic components mounted on the main surface is soldered to the cover fixing electrode,
An oscillator device, characterized in that a mounting terminal is provided on a back surface opposite to the main surface of the printed circuit board, which is connected to the side electrode and is mounted on an applied electronic device by SMD. In claim 1,
The printed circuit board is formed of a multi-layered green sheet, and includes an area on which the oscillator and electronic components are mounted and a wiring pattern forming area on a side located on the back surface of the upper layer sheet constituting the main surface. And having a ground electrode connected to the ground terminal,
The oscillator has a direction parallel to the substrate surface of the printed circuit board by the cap-shaped metal cover, and in a direction perpendicular to the printed circuit board, by the metal cover of the oscillator itself and the cap-shaped metal cover, and further by the ground electrode, An oscillator device characterized by shielding external radiation noise and blocking external noise entering through the power supply terminal by the capacitor. In claim 2,
The printed circuit board is formed by laminating an intermediate layer sheet and a lower layer sheet in this order on the surface side opposite to the main surface of the upper layer sheet,
On the back surface opposite to the main surface of the lower layer sheet, a mounting terminal for connecting to the side electrode and mounting the SMD on the applied electronic device is formed,
The ground electrode pattern is formed on either the surface of the middle layer sheet facing the upper layer sheet or the surface facing the lower layer sheet,
The oscillator has a direction parallel to the substrate surface of the printed circuit board by the cap-shaped metal cover, and in a direction perpendicular to the printed circuit board, by the metal cover of the oscillator itself and the cap-shaped metal cover, and further by the ground electrode, An oscillator device characterized by shielding external radiation noise and blocking external noise entering through the power supply terminal by the capacitor. In claim 2,
The printed circuit board is formed by laminating a lower layer sheet on the surface side opposite to the main surface of the upper layer sheet,
On the back surface opposite to the main surface of the lower layer sheet, a mounting terminal for connecting to the side electrode and mounting the SMD on the applied electronic device is provided,
A pattern of the ground electrode is formed on the surface of the lower sheet facing the upper sheet,
The oscillator has a direction parallel to the substrate surface of the printed circuit board by the cap-shaped metal cover, and in a direction perpendicular to the printed circuit board, by the metal cover of the oscillator itself and the cap-shaped metal cover, and further by the ground electrode, An oscillator device characterized by shielding external radiation noise and blocking external noise entering through the power supply terminal by the capacitor.

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