JPH0458604A - Crystal oscillation circuit - Google Patents

Abstract

PURPOSE:To send oscillating signals with various frequencies and to minimize the amount area by containing crystal oscillation elements having different natural vibrating frequency characteristics, a required signal processing means and an output buffer means into one and the same package. CONSTITUTION:A signal processing circuit 12 outputs various frequency signals in response to natural vibrating frequency characteristics of each of crystal oscillation elements 10a-10d and drives a frequency divider circuit 12a and a resonance frequency extraction circuit 12b or the like to output various frequency signals such as frequencydivided signal and a resonance frequency signal. An output buffer circuit 13 converts various frequency signals from the signal processing circuit 12 into plural pulse signals P1-Pn used as, e.g. reference clock pulses for various ICs and they are outputted. The various ICs receive a pulse signal with a preset frequency among the pulse signals P1-Pn as a reference clock pulse required for the operation. A crystal oscillation circuit is integrated in one and same package 11 together with the crystal oscillation elements 10a-10d. Thus, in the case of the crystal oscillation circuit mounted on a printed circuit board, a required minimum occupied area is attained for the crystal oscillation circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a crystal oscillation circuit that utilizes a crystal oscillation element and is integrated into an integrated circuit.

(Prior Art) Conventionally, electronic devices such as microcomputers, etc.
An oscillation circuit that oscillates a reference signal such as a clock pulse of a predetermined frequency is essential.

Although various types of oscillation circuits have been developed, a crystal oscillation circuit using a crystal oscillation element (crystal resonator) is well known because it is stable in terms of frequency and structure.

A crystal oscillation circuit is a circuit that applies voltage to a crystal oscillation element having a predetermined natural oscillation frequency to oscillate a signal at a predetermined frequency. Such crystal oscillation circuits are packaged as individual components and mounted on printed circuit boards together with integrated circuits (ICs) that constitute various electronic circuits of electronic devices.

In recent years, with the development of IC technology, large-scale integrated electronic circuits have been developed. For this reason, a large number of NICs are increasingly being mounted on the same printed circuit board. Along with this, base signals of various frequencies are required depending on the operation of the IC, and a plurality of crystal oscillation circuits are required.

(Problems to be Solved by the Invention) A large number of various ICs are mounted on the same printed circuit board, and electronic devices are becoming relatively smaller. In this case, reference signals of various frequencies are required depending on the operation of various ICs. Therefore, it is required to mount a plurality of crystal oscillation circuits corresponding to various frequencies on the same printed circuit board. However, when a number of crystal oscillation circuits corresponding to the required frequency are mounted on the same printed circuit board, the area occupied by the crystal oscillation circuits increases, which ultimately becomes a factor that hinders miniaturization of the device.

An object of the present invention is to provide a crystal oscillation circuit that can oscillate signals of various frequencies according to the operation of an electronic circuit, and can minimize the mounting area to the necessary minimum, resulting in miniaturization of the device. There is a particular thing.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention provides a plurality of crystal oscillation elements having different natural oscillation frequency characteristics, signals such as frequency division processing and resonant frequency extraction processing, etc. in the same package. This is a crystal oscillation circuit that houses signal processing means for processing and output buffer means for outputting a plurality of types of frequency signals to an external circuit.

With such a configuration, it is possible to oscillate signals of various frequencies depending on the operation of the electronic circuit.

Furthermore, by packaging, the mounting area can be minimized when mounted on a printed circuit board.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a crystal oscillation circuit according to the same embodiment. This circuit includes a plurality of crystal oscillation elements (A
-D) lOa -10d , a signal processing circuit 12 and an output buffer circuit 13 are housed therein.

Each of the crystal oscillation elements 10a to 10d has different natural oscillation frequency characteristics, and is driven when a predetermined voltage is supplied.

The signal processing circuit 12 includes a frequency dividing circuit 1 as shown in FIG.
2a, a resonance frequency extraction circuit 12b, etc., and outputs various signals having different frequencies in accordance with driving of each crystal oscillation element 10a to 10d. The output buffer circuit 13 includes a pulse generation circuit 13a, which converts various frequency signals outputted from the signal processing circuit 12 into pulse signals, and outputs the pulse signals to an external circuit.

When such a crystal oscillation circuit is mounted on a printed circuit board, various frequency signals are output from the signal processing circuit 12 by supplying voltage to and driving each crystal oscillation element 10a to lOd. The signal processing circuit 12 outputs various frequency signals according to the natural oscillation frequency characteristics of each crystal oscillation element 10a to 10d, and also drives the frequency dividing circuit 12a and the resonance frequency extraction circuit 12b, etc. to output the frequency-divided signals and Outputs various frequency signals such as resonance frequency signals. The output buffer circuit 13 converts various frequency signals from the signal processing circuit 12 into a plurality of pulse signals P1 to P7 used as reference clock pulses for various ICs, and outputs the converted signals.

Each pulse signal P, -P, from the output buffer circuit 13 is input to various ICs mounted on a printed circuit board. The various ICs receive a pulse signal of a preset frequency from among the pulse signals P1 to P as a reference clock pulse necessary for operation.

In this manner, the crystal oscillator circuit of the same embodiment can supply reference tallock pulses of various frequencies necessary for operation to various ICs mounted on the same printed circuit board. Therefore, on the same printed circuit board,
Each QI operates with reference clock pulses of various frequencies.
By implementing C, it becomes possible to construct complex and large-scale electronic circuits.

In this case, the crystal oscillation circuit includes each crystal oscillation element 10a-1.
0d are integrated in the same package 11. Therefore, when mounted on a printed circuit board, the area occupied by the crystal oscillation circuit can be minimized. In other words, conventionally, depending on various frequencies,
It is necessary to prepare a plurality of crystal oscillation circuits, which are individual components configured for each natural vibration frequency. In contrast, in this embodiment, it is possible to prepare a single circuit using the same package.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to provide a crystal oscillation circuit that can oscillate signals of various frequencies according to the operation of an electronic circuit and can minimize the mounting area. can. By mounting such a crystal oscillator circuit on a printed circuit board, compared to the conventional method (7), when various ICs requiring various frequency signals are mounted on the same printed circuit board, the number of ICs can be reduced. It can be increased.

Therefore, it is possible to configure a relatively large-scale electronic circuit on the same printed circuit board, and as a result, it becomes easy to downsize a device made of electronic circuits.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a crystal oscillation circuit according to an embodiment of the present invention, and FIG. 2 is a block diagram illustrating main parts of the crystal oscillation circuit according to the embodiment. 10a-10d...Crystal oscillation element, 11...Package, 12...Signal processing circuit, 13...7 output buffer circuits. Applicant's agent Patent attorney Takehiko Suzue Figure 2 Figure 1

Claims (1)

[Claims] A plurality of crystal oscillation elements each having different natural oscillation frequency characteristics, and performing signal processing such as frequency division processing and resonant frequency extraction processing according to the driving of each crystal oscillation element, a signal processing means for outputting various frequency signals; an output buffer means for outputting the plurality of frequency signals outputted from the signal processing means to an external circuit; each of the crystal oscillation elements, the signal processing means, and the output. A crystal oscillation circuit comprising packaging means for accommodating each of the buffer means in the same package.