JP2003332845A - Crystal oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crystal oscillator capable of obtaining a stable oscillation frequency by configuring the crystal oscillator so as to externally radiate generated heat of an active device of a crystal oscillation circuit through a lid body thermally connected to the active device and reducing the influence an a piece of quartz crystal to be heated by the heat generated by the operation of the active device. <P>SOLUTION: This crystal oscillator comprises a container 1, a crystal resonator 2 housed in the container 1, the active device 4 constituting the crystal oscillator with the crystal resonator 2, and the lid body 6 for the container thermally connected to the active device 4. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crystal oscillator for radiating heat generated by an active element to the outside.

[0002]

2. Description of the Related Art It is known that the oscillation frequency of a crystal oscillator using a crystal oscillator is stable. The main cause of the fluctuation of the oscillation frequency is the change of the resonance frequency due to the temperature change of the crystal piece. For example, in the case of a crystal oscillator using an AT-cut crystal unit that is most frequently used, several tens of ppm with respect to a temperature change of -30 to 80 ° C
A frequency change of several hundred ppm is generated.

On the other hand, in crystal oscillators, transistors and ICs are used.
, Etc., are used, and external power must be supplied to operate these active elements, which causes heat generation. In particular, the active element used in the recently sought-after high-frequency oscillator circuit generates a large amount of heat, and since the active element and the crystal element are arranged close to each other in order to reduce the size, the heat applied to the crystal element is reduced. It is difficult to avoid this because it has a large impact.

Therefore, the crystal element has a problem that the resonance frequency fluctuates under the influence of heat generation of the active element, and the oscillation frequency fluctuates due to this fluctuation.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and reduces the influence of heat generated by an active element of a crystal oscillator circuit on a crystal piece, thereby obtaining a stable oscillation frequency. It is an object of the present invention to provide a crystal oscillator that can be manufactured.

[0006]

According to a first aspect of the present invention, a container, a crystal resonator housed in the container, an active element that constitutes a crystal oscillator together with the crystal resonator, and a thermal element for the active element. A crystal oscillator, comprising: the container lid coupled to
In the crystal oscillator according to 1 above, the lid of the container is made of metal and is fixed to the active element with an adhesive.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIG.
It will be described in detail with reference to the side sectional view shown in FIG. Container 1
For example, it is made of ceramic and has an opening on the upper surface. The crystal piece 2 is housed in the inner bottom of the container 1. Crystal piece 2
Has been processed into a predetermined resonance frequency in advance to form an excitation electrode on the plate surface.

Then, a holding electrode is formed on the inner bottom surface of the container 1, and the lead-out end of the electrode of the crystal piece 2 is fixed thereto with a conductive adhesive 3 to hold and electrically connect. In this state, for example, the electrodes of the crystal blank 2 are connected to an external measuring circuit or oscillation circuit to measure the resonance frequency.

Then, mass is added to or removed from the upper electrode of the crystal blank 2 to adjust the resonance frequency to a target frequency. Further, for example, face down bonding (FD) on the upper surface of the crystal piece 2.
According to B), the active element 4 is mounted to form a crystal oscillation circuit. In this case, a mounting electrode for mounting the active element 4 is formed in advance on the upper surface of the portion of the crystal element 2 where piezoelectric vibration is not performed, and a circuit element such as a capacitor is also mounted if necessary.

Further, an electrode for mounting on a printed circuit board or the like is formed on the outer bottom surface of the container 1, and an operating power is supplied from the outside through this electrode and an oscillation output is output to the outside. . Then, the adhesive 5 is applied to the upper surface of the active element 4, and the opening of the container 1 is covered by the lid 6 made of a thin metal plate.
For example, it is sealed by soldering. In this case, the active element 4 and the lid 6 are thermally coupled via the adhesive 5.

With such a configuration, it is possible to supply the operating power from the outside to operate the crystal oscillation circuit and output the oscillation output to the outside. The heat generated by the active element 4 due to the oscillation operation is transmitted to the lid 6 via the adhesive 5 and is radiated to the outside. Therefore, the crystal piece 2 due to the heat generated by the active element 2
Can be reduced, and in particular, the fluctuation of the oscillation frequency due to the change of the temperature of the crystal blank 2 can be reduced.

The present invention is not limited to the above embodiment. For example, in the above description, the active element 4
Although the FDB is mounted on the crystal piece 2 in the above, a circuit pattern may be formed on the inner bottom surface of the container 1 and the active element 4 may be mounted on the circuit pattern. Further, although the active element 4 and the lid body 6 are thermally coupled with the adhesive 5 has been described, it is sufficient that a good heat transfer action can be realized between the active element 4 and the lid body 6.

Therefore, a metal piece or the like having good thermal conductivity may be interposed between the active element 4 and the lid 6, or the upper surface of the active element 4 may directly contact the lid 6. You may Furthermore, in the above-described embodiment, the container 1 is described as having a structure in which it is hermetically sealed by the lid body 6. However, when the quartz piece 2 that is sealed in advance in an airtight manner is used, an opening communicating with the outside is provided. You may make it use the container 1 which has. In this case, the retention of heat in the container 1 can be reduced, which is desirable in order to reduce the influence of heat generation of the active element 4.

[0014]

As described in detail above, according to the present invention,
It is possible to provide a crystal oscillator that can reduce the influence of heat generated by an active element on a crystal element, and that is suitable for downsizing and high-frequency operation and that can achieve good frequency stability.

[Brief description of drawings]

FIG. 1 is a side sectional view of an embodiment of the present invention.

[Explanation of symbols]

1 ·· Container 2 ... Crystal pieces 3 ··· Conductive adhesive 4 ·· Active elements 6 ... Lid

Claims (2)

[Claims] 1. A container, a crystal resonator housed in the container, an active element that constitutes a crystal oscillator together with the crystal resonator, and a lid of the container thermally coupled to the active element. A crystal oscillator characterized by that. 2. A crystal oscillator according to claim 1, wherein the lid of the container is made of metal and is fixed to the active element with an adhesive.