JPH03171808A - High-stability crystal oscillator - Google Patents

Abstract

PURPOSE:To reduce the power consumption and to miniaturize the external form by using a double rotation crystal oscillator and using a thermostat at <=30 deg.C and using a compensating circuit at >30 deg.C to perform the temperature compensation. CONSTITUTION:A crystal oscillator 1 using a crystal vibrating plate whose Y plate is rotated at bout 35 deg. with the X axis as the center and is rotated about 15 deg. with the Z' axis as the center is put in a thermostatic chamber 2 at about 30 deg.C, and a high temperature compensating circuit 3 for temperature compensation for >30 deg.C is connected. The crystal oscillator 1 is heated in the thermostat 2 to perform temperature compensation for <=30 deg.C, and the temperature compensating circuit 3 is used to perform temperature compensation for >30 deg.C. Thus, a high-stability crystal oscillator is obtained which has a low power consumption, a small external form, and a stable frequency.

Description

[Detailed description of the invention]

<Object of the present invention> [Industrial Field of Application J] The present invention relates to a highly stable crystal oscillator using a double rotation crystal resonator. [Conventional technology 1] As a highly stable crystal oscillator, an AT-cut crystal resonator has conventionally been used, and the turning point is 580 Iy-
I/TX★Taman▼Sefu Yamaguchi Masuhina Lf #-m+. ▼C The crystal resonator was placed in a thermostatic chamber, the temperature of the thermostatic chamber was adjusted to the turning point of the crystal resonator, and an oscillation circuit was connected to generate oscillation. Also, an oscillator using only a compensation circuit without high temperature heating, such as T
For CXO, the frequency stability was limited to 5XIO-'.

[Problem to be Solved by the Invention 1] However, a highly stable oscillator using a thermostatic oven consumes a large amount of power, and since it is used at high temperatures, a heat insulating material is used, resulting in a large external size. Furthermore, the oscillator based on the swamp compensation circuit had a limited stability. 1.Object of the present invention 1.An object of the present invention is to provide a highly stable crystal oscillator with low power consumption, small external size, and stable frequency. <Structure of the present invention> [1,000 steps to solve the problem In the present invention, a so-called double rotation crystal oscillator is used, and the frequency temperature is particularly low at 30° C. or lower.
Hiba r, Le] 1◆, I-EllmM-A {JgTlfl
-BIJ-,V Up to 30°C, it is warmed in a constant temperature bath, and M@ is performed by heating the low temperature side, and above about 30°C, compensation is performed using a temperature compensation circuit. [Operation and Example 1] FIG. 3 is an explanatory view showing a cut surface of a crystal resonator used in the present invention. A crystal resonator is used in which the Y plate is rotated about 35 degrees around the X axis and further rotated about 15 degrees around the 2' axis. In the figure, the first rotation is shown by one arrow, and the second rotation is shown by two arrows. As shown in FIG. 2, the characteristics of the crystal resonator due to this no-knot angle are such that the frequency decreases at low temperatures from around 30°C. On the other hand, the high temperature side has a frequency temperature characteristic in which the frequency increases relatively slowly. In the present invention, this crystal oscillator is used and is kept at a constant temperature of about 30° C. or lower. On the high temperature side of about 30℃ or higher, a direct type 1-degree compensation circuit that uses a thermistor and connects a compensation circuit combined with a capacitor to the crystal resonator, or a thermistor and a resistor that generates a DC compensation voltage and connects it in series with the crystal resonator. The temperature M is adjusted using an indirect *i circuit that applies the voltage to a variable capacitance diode connected to the . A crystal oscillator using a conventional AT cut has a temperature of 50 to 80°C.
Until now, the crystal resonator and oscillation circuit had been heated, which consumed a large amount of power, but with the present invention, approximately 30
Because it only heats up to ℃, power consumption is low.
Furthermore, since the high temperature side is also compensated by the temperature compensation circuit, the frequency is stabilized. Of course, the same effect can be achieved even if a so-called digital temperature compensation circuit using an IC memory or the like is used to compensate for high temperature cases. Effects of the Invention> The present invention makes it possible to realize a highly stable crystal oscillator that consumes less power and has a smaller external size than conventional highly stable oscillators, and also has a compensation circuit only on the high temperature side. It was easier than anything else.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the oscillator of the present invention, Fig. 2 is an explanatory diagram showing the frequency-temperature characteristics of the crystal resonator used in the present invention, and Fig. 3 is an explanatory diagram showing the crystal axis of the crystal resonator used in the present invention. be. License applicant Kinseki Co., Ltd. 2nd

Claims (1)

[Claims] (1) In a highly stable crystal oscillator in which the crystal resonator is placed in a constant temperature bath, the Y plate is rotated approximately 35 degrees around the X axis, and then the Z
A crystal oscillator using a crystal diaphragm rotated about 15 degrees around its axis is placed in a constant temperature bath at about 30 degrees Celsius, and is connected to a high temperature temperature compensation circuit that compensates for the temperature above about 30 degrees Celsius. Highly stable crystal oscillator.