JP2009176866A - Electronic circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce noise given off from a circuit pattern connected to electronic elements without lowering a withstand voltage between the input/output terminals of the electronic elements such as a photocoupler, a phototransistor and an insulation amplifier and without inviting the increase of substrate weight and cost increase. <P>SOLUTION: The electronic circuit board includes a substrate 1, a first electronic element 2 mounted on the surface of the substrate 1, and a second electronic element 3 mounted on the back surface of the substrate 1. The first and second electronic elements 2 and 3 face each other through the substrate 1, the input end 2a of the first electronic element 2 and the output end 3b of the second electronic element 3 face each other through the substrate 1, and the output end 2b of the first electronic element 2 and the input end 3a of the second electronic element 3 face each other through the substrate 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic circuit board configured by mounting electronic elements on a printed circuit board, and to an electronic circuit board in which noise from an opto device is reduced.

  Conventionally, an electronic circuit board configured by mounting electronic elements on a printed board has been used. Among these electronic elements, devices that perform signal transmission / reception using light, such as photocouplers, phototransistors, and insulation amplifiers, consume more current than general ICs, and are emitted especially when used at high frequencies. The noise level is high.

  As an electronic circuit board capable of reducing such noise, Patent Document 1 describes an electronic circuit board in which a low impedance pattern for noise absorption is arranged on a printed board. This electronic circuit board is a printed wiring board in which a printed wiring area is formed for each function of a circuit, and each circuit is electrically insulated and connected by a signal transmission element that transmits only a signal. By forming a low impedance pattern connected to the signal ground, each pattern absorbs external noise that enters the logic circuit section via the input / output circuit section, and prevents malfunction due to external noise in the logic circuit section. It is a thing.

Japanese Patent Laid-Open No. 10-145031

  By the way, in an electronic circuit board that aims to reduce noise by arranging low impedance patterns as described above, for example, a low impedance pattern is arranged between input / output terminals of a photocoupler. May decrease.

  In addition, the addition of a low impedance pattern causes an increase in substrate weight and cost.

  Therefore, the present invention has been made in view of the above circumstances, and there is no risk of reducing the withstand voltage between input and output terminals of electronic elements such as photocouplers, phototransistors, and insulation amplifiers. An object of the present invention is to provide an electronic circuit board in which noise emitted from circuit patterns connected to these electronic elements is reduced without causing an increase or cost increase.

  In order to solve the above-described problems and achieve the object, an electronic circuit board according to the present invention has any one of the following configurations.

[Configuration 1]
A substrate, a first electronic element mounted on the front surface of the substrate, and a second electronic element mounted on the back surface of the substrate, the first and second electronic elements facing each other through the substrate The input end of the first electronic element and the output end of the second electronic element are opposed to each other through the substrate, and the output end of the first electronic element The input end of the second electronic element is a position facing each other with the substrate interposed therebetween.

[Configuration 2]
A substrate, an electronic device mounted on the surface of the substrate, a first circuit pattern formed on the surface of the substrate, and a second circuit pattern formed on the back surface of the substrate, the input terminal of the electronic device And the first circuit pattern connected to one of the output terminals and the second circuit pattern connected to the other of the input terminal and the output terminal via a conduction hole face each other through the substrate. It is characterized by being a position to perform.

  In the electronic circuit board according to the present invention having the configuration 1, the input end of the first electronic element and the output end of the second electronic element are positioned to face each other with the substrate interposed therebetween. Since the output end of the electronic element and the input end of the second electronic element are opposed to each other through the substrate, the radiation noise from the circuit pattern connected to these terminals cancels each other out. Radiation noise can be reduced without adding an absorption pattern.

  In the electronic circuit board according to the present invention having the configuration 2, the first circuit pattern connected to one of the input end and the output end of the electronic element and the conduction hole in the other of the input end and the output end. The second circuit patterns connected to each other are positioned so as to face each other through the substrate, so that radiation noises from these circuit patterns cancel each other, so that no noise absorption pattern is added. , Radiation noise can be reduced.

  That is, the present invention eliminates the risk of lowering the withstand voltage between the input and output terminals of electronic elements such as photocouplers, phototransistors, and insulation amplifiers, and does not increase the substrate weight or increase the cost. It is possible to provide an electronic circuit board in which noise emitted from a circuit pattern connected to an element is reduced.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a perspective view showing a configuration of a first embodiment of an electronic circuit board according to the present invention.

  As shown in FIG. 1, an electronic circuit board according to the present invention includes a board 1, a first electronic element 2 mounted on the front surface of the board, and a second electronic element 3 mounted on the back surface of the board. It is configured with. The first and second electronic elements 2 and 3 are, for example, photocouplers, phototransistors, insulation amplifiers, and the like. These first and second electronic elements 2 and 3 are preferably the same or approximate standard electronic elements.

  The first and second electronic elements 2 and 3 are arranged at positions facing each other with the substrate 1 interposed therebetween. In addition, the input end 2 a of the first electronic element 2 and the output end 3 b of the second electronic element 3 are positioned to face each other with the substrate 1 interposed therebetween. The output end 2 b of the first electronic element 2 and the input end 3 a of the second electronic element 3 are positioned to face each other with the substrate 1 interposed therebetween.

  In this electronic circuit board, the current direction of the drive signal supplied to the first electronic element 2 mounted on the surface of the substrate 1 and the second electronic element 3 mounted on the back surface of the substrate 1 are supplied. The directions of the drive signal currents are opposite to each other across the substrate 1. Therefore, the magnetic fields (electromagnetic noise) radiated from the circuit patterns connected to the input / output terminals 2a, 2b, 3a and 3b of the electronic elements 2 and 3 cancel each other, and the radiation noise is reduced.

  The first and second electronic elements 2 and 3 are not limited to opto-devices such as photocouplers and phototransistors, but may be ordinary integrated circuits (ICs), and may be magnetic elements such as transformers and inductors. It may be a device that uses. Further, one of the first and second electronic elements 2 and 3 is not used as an electronic element, but cancels the magnetic field (electromagnetic noise) radiated from the drive signal supplied to the other electronic element. For the purpose only, only a resistor and a circuit pattern corresponding to the electronic element may be provided.

[Second Embodiment]
FIG. 2 is a perspective view showing the configuration of the second embodiment of the electronic circuit board according to the present invention.

  As shown in FIG. 2, the electronic circuit board according to the present invention includes a board 1, an electronic element 2 mounted on the surface of the board 1, a first circuit pattern 4 formed on the surface of the board 1, You may comprise and comprise the 2nd circuit pattern 6 formed in the back surface of the board | substrate 1. FIG.

  In the electronic circuit board, the first circuit pattern 4 is connected to one of the input end 2a and the output end 2b of the electronic element 2, in FIG. 2, the input end 2a. The second circuit pattern 6 is connected to the other of the input end 2 a and the output end 2 b, in FIG. 2, to the output end 2 b through a conduction hole (via) 5. And these 1st and 2nd circuit patterns 4 and 6 are the positions which mutually oppose through the board | substrate 1. FIG.

  In this electronic circuit board, the direction of the drive signal current flowing through the first circuit pattern 4 on the front surface of the substrate 1 and the direction of the drive signal current flowing through the second circuit pattern 6 on the back surface of the substrate 1 are: The substrates 1 are opposite to each other across the substrate 1. Therefore, the magnetic fields (electromagnetic noise) radiated from the circuit patterns 4 and 6 connected to the input / output terminals 2a and 2b of the electronic element 2 cancel each other, and the radiated noise is reduced.

1 is a perspective view showing a configuration of a first embodiment of an electronic circuit board according to the present invention. It is a perspective view which shows the structure of 2nd Embodiment of the electronic circuit board which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 1st electronic element 2a Input terminal 2b Output terminal 3 2nd electronic element 3a Input terminal 3b Output terminal 4 1st circuit pattern 5 Conduction hole 6 2nd circuit pattern

Claims (2)

A substrate,
A first electronic element mounted on the surface of the substrate;
A second electronic element mounted on the back surface of the substrate,
The first and second electronic elements are arranged at positions facing each other through the substrate,
The input end of the first electronic element and the output end of the second electronic element are positioned to face each other through the substrate,
An electronic circuit board, wherein an output end of the first electronic element and an input end of the second electronic element are opposed to each other with the substrate interposed therebetween. A substrate,
An electronic device mounted on the surface of the substrate;
A first circuit pattern formed on the surface of the substrate;
A second circuit pattern formed on the back surface of the substrate,
The first circuit pattern connected to one of the input end and the output end of the electronic element, and the second circuit pattern connected to the other of the input end and the output end via a conduction hole Is a position facing each other with the substrate interposed therebetween.

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