JPS6331204A - Optical output crystal oscillator - Google Patents

Abstract

PURPOSE:To decrease the change in the oscillating frequency due to load fluctuation by converting an electric output of a crystal oscillator into an optical signal, leading its optical signal externally through an optical conductor thereby preventing the effect of external noise onto signal transmission. CONSTITUTION:An optical output crystal oscillator 10 uses a crystal vibrator 1 for its oscillating element, an electro-optic conversion element 11 converts an electric output of an oscillation circuit 2 into an optical signal and an optical conductor 7 such as an optical fiber is used as a conductor and led out externally. In using the oscillator 10 for engine control, the optical conductor 7 is connected to a photodetection section 14 of a control device for an engine room. Thus, the effect due to external noise on the signal transmission is prevented and the change in the oscillating frequency due to load fluctuation is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to an optical output crystal oscillator that converts the output of a crystal oscillator into optical No. 43 and outputs it to the outside.

(Background of the invention) Crystal oscillators (well, because they can obtain a highly stable output frequency, they have been widely used as a reference source in various electronic devices. There is a demand for a crystal oscillator that is used in various environments such as for I-roll and has good environmental characteristics such as 11ri shock, heat, and noise.

(Conventional technology) FIG. 4 is a diagram showing a general configuration of a crystal oscillator.

That is, a crystal oscillator uses a crystal oscillator 1 as an oscillation element, forms an oscillation circuit 2 together with other circuit elements such as transistors, and encapsulates each of these elements in a housing to generate an electrical output. For example, in the case of engine control, it is difficult to directly mount a crystal oscillator in the engine compartment because it generates high heat in the engine compartment. Place the ffi + near the dash board to avoid the influence of heat, and conduct electricity from the output terminal 3 of the crystal oscillator to 91 shown in Figure 5.
was sent to the power receiving section 5 of the engine control equipment through an extension 17.

(Disadvantages of the prior art) However, in a crystal oscillator having such a configuration, there is a risk that, for example, electrical shoe noise caused by engine drive may be superimposed on the conductive path 17 and adversely affect the output signal, resulting in 4W operation for engine control. there were. (7) For example, if you try to install a crystal oscillator directly in the engine room, heat resistance and
The problem was that a four-quake structure was required, making the equipment expensive and complicated. Furthermore, crystal oscillators have the disadvantage that their output frequency changes due to load fluctuations, since the electrical output is sent directly to the load.

(Object of the Invention) An object of the present invention is to provide an optical output crystal oscillator that prevents ti caused by external noise, vibration, and shock during signal transmission, and reduces changes in oscillation frequency due to load fluctuations.

(Solution and operation) The present invention converts the electrical output of a crystal oscillator into an optical signal,
The solution is to lead out the optical signal to the outside through a light guide, which has the effect of electrically separating the crystal oscillator and the power receiving side. The invention will be described in detail below.

(Example) FIG. 1 is a simplified diagram of an optical output crystal oscillator for explaining the present invention in detail. Note that the same parts as those in the above-mentioned figures are given the same numbers and explained.

That is, the optical output crystal oscillator 10 indicated by the dotted line frame in the figure is
Using a crystal oscillator 1 as an oscillation element, the electrical output of an oscillation circuit 2 is converted into an optical signal by an electro-optic conversion element 11, and a light guide 12 such as an optical fiber is led out to the outside as an output terminal to form a t-co configuration. . Note that FIG. 2 is a diagram showing an example in which the electro-optical conversion element 11 is a light emitting diode 13.
Others such as laser diodes are used.

In the case of using it for engine control, for example, as shown in FIG. 3, the optical output crystal oscillator 10 is arranged near the dash board of the driver's seat (not shown), and the light guide 12 is extended. It is connected to the light receiving section 14 of the control equipment in the engine room.

The light receiving section 14 includes a light-to-electrical conversion element 15 such as a photodiode, and converts an optical signal into an electrical signal and supplies the electrical signal to the power receiving section 5 .

Therefore, in the optical output crystal oscillator 10 having such a configuration,
First, it uses a system that mounts a crystal oscillator directly in the engine room, so it can reduce the effects of heat and shock without having to build a structure like Okawa. Since the output terminal is used as the optical conductor 12 and the signal is transmitted by light, it is possible to prevent the control equipment from malfunctioning without being superimposed on external electrical shoe sounds. Further, since the crystal oscillator and the power receiving side are electrically separated and independent through the connection 17 to the light guide, it is possible to reduce frequency changes of the crystal oscillator due to load fluctuations.

(Other Matters) In this embodiment, the optical output crystal oscillator is used for automobile engine control, but the optical output of the present invention can also be used, for example, when the crystal oscillator is used in an environment where electromagnetic waves are easily generated. Crystal oscillators are useful and are not limited to the example application.

(Effect of the invention) The present invention converts the electrical output of a crystal oscillator into an optical signal,
Since the solution is to lead this optical signal to the outside through a light guide, the present invention aims to provide an optical output crystal oscillator that prevents the influence of external shoe noise during signal transmission and reduces changes in oscillation frequency due to load fluctuations. purpose.

[Brief explanation of drawings]

FIG. 1 is a simplified diagram of an optical output crystal oscillator that explains the present invention in detail, and FIG.
7t: A diagram showing an example of a light output crystal oscillator. FIG. 3 is a diagram showing a usage system of the light output crystal oscillator. FIG. 4 is a simplified diagram of a conventional crystal oscillator, and FIG. 5 is a diagram showing a system using the crystal oscillator. Figure 4 5g Shipro 22 countries -- 1 Middle

Claims (1)

[Claims] 1. An optical output crystal oscillator, characterized in that an electrical output of the crystal oscillator is converted into an optical signal, and the optical signal is guided to the outside through a light guide.