JP2001127579A - Piezoelectric vibration and piezoelectric oscillator using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized crystal oscillator that can accurately detect temperature of a crystal vibrator. SOLUTION: In the piezoelectric vibrator provided with the piezoelectric vibration chip, a ceramic package with a recessed part to contain the piezoelectric vibration chip, and a cover to seal the recessed part, at least one thick film print thermister is provided to the recessed part of the ceramic package or on an outer face of the ceramic package. Since the component mount area of the ceramic wiring board on with components of the piezoelectric oscillator are mounted can effectively be utilized, the piezoelectric oscillator can sufficiently be miniaturized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric vibrator and a piezoelectric oscillator, and more particularly, to a small crystal oscillator having excellent frequency-temperature characteristics and a crystal vibrator used therefor.

[0002]

2. Description of the Related Art It is generally desired to use a temperature-compensated crystal oscillator as a reference transmission source used in a portable telephone because it is desired to have excellent frequency-temperature characteristics. Such a temperature-compensated crystal oscillator includes a direct-temperature-compensated crystal oscillator configured to insert and connect a temperature-compensation circuit having a thermistor into an oscillation loop, and a direct-current (DC) generated by a voltage generation circuit composed of a thermistor and a resistor. The type is roughly classified into two types: an indirect temperature compensation type crystal oscillator configured to supply a voltage as a bias to a variable capacitance diode inserted and connected to an oscillation loop. Since it is necessary to accurately detect the temperature of the crystal unit in a short time, it is generally configured that the thermistor and the crystal unit are arranged close to each other.

FIG. 4 is a perspective view showing the structure of a conventional crystal oscillator. In the crystal oscillator 100 shown in FIG. 1, a thick-film printed thermistor 102 and electronic components 103 such as capacitors, resistors, and transistors are arranged on a surface 101 of a ceramic wiring board, and only the thick-film printed thermistor 102 is covered. A quartz crystal unit 104 of a surface mount type is mounted, and furthermore, these upper parts are configured to be covered by a case (not shown).

That is, the above-described configuration uses a thick-film printing thermistor without selecting the use of a chip-type thermistor, and further mounts the crystal unit 104 on top of this. As a result, the mounting area of the thermistor is substantially eliminated to reduce the mounting area of the components, and as a result, the crystal oscillator can be downsized. In the thus configured crystal oscillator 100, since the thermistor 102 is in contact with the bottom surface of the crystal oscillator 104, the temperature of the crystal oscillator 104 can be directly detected, and the ceramic wiring Substrate 101 and crystal unit 1
Since it is arranged so as to be sandwiched between the quartz oscillator 104 and the temperature sensor, the temperature of the crystal unit 104 can be detected very accurately because it is not affected by the temperature change caused by the flow of the outside air. It has excellent temperature characteristics.

[0005]

However, in the crystal oscillator configured as described above, the ceramic wiring board 1
In addition to the fact that there is no room in the component mounting area of No. 01, there is a limit in reducing the size of the components used and the reduction in the number of components, so that it is impossible to respond to the demand for further miniaturization. There was a problem.

For example, it is conceivable that a resistor constituting the oscillation circuit is formed on a printed wiring board by a thick-film printed resistor, and is disposed below the quartz oscillator together with the thick-film printed thermistor. Since a small one is used as 104, other thick-film printing resistors cannot be arranged next to the thick-film printing thermistor 102 to cover them. As a result, a further substantial reduction in the component mounting area is not possible. Because it was possible, the miniaturization of the crystal oscillator could not be expected.

An object of the present invention is to provide a small crystal oscillator having excellent frequency temperature characteristics by solving the above problems of the piezoelectric oscillation circuit.

[0008]

According to a first aspect of the present invention, there is provided a piezoelectric vibrating reed comprising:
In a piezoelectric vibrator having a ceramic container having a concave portion for accommodating the piezoelectric vibrating piece and a lid for sealing the concave portion, in a concave portion of the ceramic container, or in the ceramic container Is characterized in that at least one thick-film printing thermistor is provided on the outer surface thereof.

In a piezoelectric vibrator provided with a piezoelectric vibrating piece, a ceramic container having a recess for accommodating the piezoelectric vibrating piece, and a lid for sealing the recess, It is characterized in that at least one thick-film printing thermistor is provided on the bottom surface in the recess or the bottom surface on the outside of the ceramic container.

According to a third aspect of the present invention, there is provided a piezoelectric oscillator including the piezoelectric vibrator according to the first or second aspect.

According to a fourth aspect of the present invention, in addition to the third aspect, there is provided a piezoelectric oscillator including a piezoelectric vibrator, an oscillation circuit, and a printed wiring board for mounting the same.
At least one resistance element constituting the oscillation circuit is a thick-film printed resistance formed on the printed wiring board,
The piezoelectric vibrator is disposed so as to cover the thick-film printing resistor.

According to a fifth aspect of the present invention, in addition to the third or fourth aspect, the piezoelectric oscillator is a temperature-compensated piezoelectric oscillator, and the thick-film printing thermistor is a temperature compensation circuit or a temperature compensation voltage generation circuit. It is characterized by being provided in.

According to a sixth aspect of the present invention, in addition to the third or fourth aspect, the piezoelectric oscillator includes a heater for heating the piezoelectric vibrator and a temperature control circuit. Wherein the temperature control circuit uses the thick-film printing thermistor as a temperature sensor and controls the amount of heat generated by the heater based on temperature information of the temperature sensor.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments. FIG. 1 is a perspective view showing an embodiment of a piezoelectric oscillator according to the present invention. As shown in FIG. 1A, a piezoelectric oscillator is a temperature-compensated crystal oscillator 1, and includes a crystal oscillator 2, a thick-film printed resistor 3, a thick-film printed thermistor 4, which will be described later, and other electronic components 5
And a ceramic wiring board 6 on which these components are mounted.

At this time, the thick film printed resistor 3 is disposed on the ceramic wiring board 6 so as to be covered by the crystal unit 2 mounted on the ceramic wiring board 6. As shown in FIG. 2B, the crystal unit 2 includes a crystal resonator element (not shown), a ceramic container 7 having a recess for accommodating the crystal resonator element, and a ceramic container 7 sealed. This is a surface-mount type crystal resonator provided with a metal or ceramic lid 8 for performing the operation.

In this case, in addition to the surface mount terminals 9, the thick-film printing thermistor 4 and the thick-film printing thermistor 4 are electrically connected to the outer bottom surface of the ceramic container 7. And a terminal 10 extending therefrom. The crystal oscillator 1 mounts the electronic component 5 on the ceramic wiring board 6, mounts the crystal oscillator 2 so as to cover the thick-film printed resistor 3, and further mounts the terminal 10.
And the wiring pattern of the ceramic wiring board 6 are connected in circuit.

Here, the resist film is applied to the surface of the ceramic wiring board 6 except for a wiring pattern necessary for connection with each electronic component, so that the thick-film printing resistor 3 and the thick-film printing thermistor 4 are electrically connected. There is no need to worry about conduction. In such a configuration, since the thick-film printing thermistor 4 is provided on the quartz oscillator 2 side, the adhesion between the quartz oscillator 2 and the thick-film printing thermistor 4 is enhanced, and the temperature of the quartz oscillator 2 is more accurately detected. And a thick-film printed resistor 3 on a ceramic wiring board 4 on which the quartz oscillator 2 is mounted.
By arranging also, it is possible to substantially reduce the component mounting area by the mounting space of the resistor, and as a result, it is possible to further promote downsizing of the crystal oscillator 1.

In the above description, the present invention has been described using the quartz oscillator 2 provided with the thick-film printing thermistor 4 on the bottom surface of the outer peripheral portion of the ceramic container 7, but the present invention is not limited to this. The thick-film printing thermistor 4 may be provided on any part of the ceramic container 7 or the lid 8. FIG. 2 shows another embodiment of the present invention.
FIG. 3 is a top view of a ceramic container constituting the crystal unit.

The quartz resonator 2 shown in FIG. 1 is characterized in that a thick-film printing thermistor 4 is provided on the bottom surface inside the recessed portion of the ceramic container 7, The point is that it is configured to conduct. With such a configuration, the thermistor is arranged closer to the crystal resonator element and is housed in a sealed container that is not affected by the flow of the outside air generated by the temperature change. In the case of the configuration as shown in the figure, it is possible to provide another thick-film printed part on the bottom surface of the outer peripheral portion of the ceramic container 7. Can be achieved more.

Further, the crystal oscillator 2 according to the present invention has been described as a temperature-compensated crystal oscillator. However, the crystal oscillator 2 is maintained at a constant temperature by a heater, and is used in a thermostatic oven crystal oscillator capable of obtaining highly stable frequency characteristics. It does not matter. That is, FIG.
FIG. 6 is a side view showing another embodiment of the piezoelectric oscillator according to the present invention. As shown in FIG. 1, a temperature control circuit for controlling the temperature of the heater by, for example, mounting a chip type heater 12 on the upper surface of the crystal unit 2 and using a thick-film printing thermistor provided on the crystal unit. 13 is used as a temperature sensor.

Although the constant temperature oven type crystal oscillator has been described above, if the temperature of the crystal unit can be stably maintained, it is not necessarily contained in a container made of a metal block or the like as shown in FIG. It does not have to be a structure in which the crystal unit is housed. Since the temperature of the crystal oscillator can be accurately detected by adopting the above configuration, a thermostatic oven crystal oscillator having extremely high frequency stability can be realized.

Furthermore, although the present invention has been described using a quartz oscillator as the piezoelectric oscillator, the present invention is not limited to this, and may be applied to any oscillator using a piezoelectric oscillator.

[0023]

As described above, in the piezoelectric oscillation circuit according to the present invention, since the thick-film printing thermistor is provided in the ceramic container of the piezoelectric vibrator, the component mounting area of the ceramic wiring board on which the oscillator circuit components are mounted is reduced. This makes it possible to use the piezoelectric oscillator effectively, thereby achieving an effect that the size of the piezoelectric oscillator can be sufficiently reduced.

[Brief description of the drawings]

FIG. 1A is a perspective view showing one embodiment of a piezoelectric oscillator according to the present invention. FIG. 2B is a perspective view illustrating an embodiment of a piezoelectric vibrator according to the present invention.

FIG. 2 is a top view showing another embodiment of the piezoelectric vibrator according to the present invention.

FIG. 3 is a side view showing another embodiment of the piezoelectric oscillator according to the present invention.

FIG. 4 is a perspective view showing a configuration of a conventional piezoelectric oscillator. 1,100 crystal oscillator, 2,104 crystal oscillator, 3, thick film printing resistor, 4,102 thick film printing thermistor, 5,10
3 electronic components, 6, 101 ceramic wiring board, 7 ceramic container, 8 lid, 9 surface mounting terminal, 10 terminal, 11 airtight conductor through pillar, 12 heater, 13 temperature control circuit,

Claims (6)

[Claims] 1. A piezoelectric vibrator comprising: a piezoelectric vibrating reed; a ceramic container having a recess for accommodating the piezoelectric vibrating reed; and a lid for sealing the recess. A piezoelectric vibrator comprising at least one thick-film printing thermistor in a recess of a container or on an outer surface of the ceramic container. 2. A piezoelectric vibrator comprising: a piezoelectric vibrating reed; a ceramic container having a recess for accommodating the piezoelectric vibrating reed; and a lid for sealing the recess. A piezoelectric vibrator comprising at least one thick-film printing thermistor on a bottom surface in a concave portion of a container or an outer bottom surface of the ceramic container. 3. A piezoelectric oscillator comprising the piezoelectric vibrator according to claim 1 or 2. 4. A piezoelectric oscillator comprising a piezoelectric vibrator, an oscillation circuit, and a printed wiring board for mounting the same, wherein at least one resistance element constituting the oscillation circuit is provided on the printed wiring board. 4. The piezoelectric oscillator according to claim 3, wherein the piezoelectric vibrator is a formed thick-film printed resistor, and the piezoelectric vibrator is arranged to cover the thick-film printed resistor. 5. The piezoelectric oscillator according to claim 3, wherein the piezoelectric oscillator is a temperature-compensated piezoelectric oscillator, and the thick-film printing thermistor is provided in a temperature compensation circuit or a temperature compensation voltage generation circuit. 5. The piezoelectric oscillator according to 4. 6. A thermostatic oven comprising a heater for heating a piezoelectric vibrator and a temperature control circuit, wherein the temperature control circuit uses the thick-film printing thermistor as a temperature sensor; 4. The method according to claim 3, wherein the amount of heat generated by the heater is controlled based on temperature information of the temperature sensor.
Or the piezoelectric oscillator according to claim 4.