JP2006162290A - Magnetic field measuring apparatus, current measuring apparatus provided with it, and electrical field measuring apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic field measuring apparatus capable of measuring magnetic fields, while maintaining a fixed distance between the surface of an object to be measured and a magnetic field probe, regardless of the shape of the surface of the object to be measured and accurately measuring the intensity distributions of magnetic fields of unwanted radiation. <P>SOLUTION: An alignment part 14 converts coordinates, indicated by coordinate information of the object to be measured 21 stored in a CAD data storage part 12, into coordinates of the object to be measured 21 in the coordinate axes of a moving part 13. A measuring position control part 18 moves an electric field probe 11 to a plurality of measuring positions which maintains a fixed distance from the surface of the object to be measured 21, in a predetermined direction to the moving part 13, on the basis of coordinate positions indicated by the coordinate information stored in the CAD data storage part 12. It is then possible to move the magnetic field probe 11, while maintaining an actual and fixed distance between the magnetic field probe 11 and the surface of the object to be measured 21. The intensity of magnetic fields at each measuring position is acquired by an electromagnetic field measuring device 15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a magnetic field measurement device that measures a near magnetic field generated around a measurement object, a current measurement device that measures a current flowing through a wiring of the measurement object, and a near electric field generated around the measurement object. The present invention relates to an electric field measuring apparatus.

As electronic devices become more functional and clock frequency higher, electromagnetic interference (
Electro Magnetic Interference (abbreviation EMI) is a problem. Accurate understanding of the phenomenon is important for countermeasures against electromagnetic interference. In other words, in order to prevent electromagnetic interference, it is important to first measure the magnetic field or electric field around the electronic device that causes the electromagnetic interference and accurately grasp the intensity of the electromagnetic wave generated from the electronic device.

  FIG. 14 is a perspective view showing an electromagnetic interference measuring apparatus 1 according to a first conventional technique for measuring the intensity of an electromagnetic wave generated from an electronic device. In the first conventional electromagnetic interference measuring apparatus 1, a printed wiring board 3 is set on an interference measuring antenna 2 in which winding coils are arranged in an array, and a near-field probe 4 is connected to a three-dimensional XY. The intensity distribution of the magnetic field of unwanted radiation from above the printed wiring board 3 is measured by fixing the output of the near magnetic field probe 4 with the disturbance measuring device 6 while being fixed to the tip of the transport device 5 that can be driven in the −Z direction. It is measured (see, for example, Patent Document 1). In the first conventional technique, it is possible to examine the influence of noise on an electric circuit due to three-dimensional unnecessary radiation generated from a printed wiring board.

  In the first conventional technique described above, the near-field probe 4 can be moved in the three-dimensional X-Y-Z direction, but between the near-field probe 4 and the printed wiring board 3 that is a measurement object. It is not configured to measure the intensity distribution of the unwanted radiation magnetic field while keeping the distance constant. Therefore, the intensity distribution of the unwanted radiation magnetic field cannot be measured accurately.

  FIG. 15 is an enlarged view showing the near magnetic field probe 7 and its vicinity in the electromagnetic interference wave measuring apparatus according to the second conventional technique for measuring the intensity of the electromagnetic wave generated from the electronic device. In view of the above-described problem, in the second conventional technique, a laser displacement meter 9 that measures the distance between the measurement object and the near magnetic field probe 7 is provided in the sensor position moving device 8 in which the near magnetic field probe 7 is provided, The electromagnetic wave interference data is measured by controlling the sensor position moving device 8 so that the distance between the measurement object and the near magnetic field probe 7 is constant (see, for example, Patent Document 2). With such a configuration, the distance between the near magnetic field probe 7 and the measurement object can be kept constant, and even if the surface of the measurement object is not flat, the intensity distribution of the magnetic field of the electromagnetic interference wave is reduced. Can be measured.

JP-A-6-58970 JP 2002-257883 A

  The density of components mounted on the printed circuit board, which is the measurement object, is increasing, and therefore, high-resolution electromagnetic field measurement is required to identify the wiring that causes electromagnetic interference. . In order to realize high-resolution electromagnetic field measurement, it is necessary to bring the magnetic field probe and the measurement object close enough.

  However, in the second conventional technique, the laser displacement meter 9 is provided in the sensor position moving device 8 in which the near magnetic field probe 7 is provided, so that the sensor unit including the magnetic field probe 7 and the laser displacement meter 9 becomes large, and the printed wiring board. There is a problem that the magnetic field probe cannot be sufficiently brought close to the wiring formed on the printed wiring board 3 due to the obstacle mounted on the components.

  Further, since the laser displacement meter 9 is provided in the vicinity of the near magnetic field probe 7, the invasiveness of the laser displacement meter 9 is increased, in other words, the disturbance of the electromagnetic field is increased, so that the intensity of the electromagnetic field cannot be measured correctly. There is a problem.

  Even when measuring the electric field around the printed circuit board, which is the object to be measured, there is the same problem as when measuring the magnetic field.

  The object of the present invention is to measure the magnetic field with a constant distance between the surface of the measurement object and the magnetic field probe, regardless of the shape of the surface of the measurement object, and to accurately calculate the intensity distribution of the unwanted radiation magnetic field. Regardless of the shape of the magnetic field measurement device that can be measured, the current measurement device equipped with it, and the surface of the measurement object, the electric field can be measured with the distance between the surface of the measurement object and the electric field probe constant. Another object of the present invention is to provide an electric field measuring apparatus capable of accurately measuring the intensity distribution of the electric field of unwanted radiation.

The present invention is a magnetic field measuring apparatus for measuring a magnetic field around a measurement object,
A magnetic field probe that generates a signal corresponding to the change in the magnetic field based on the change in the magnetic field;
Storage means for storing coordinate information representing coordinates indicating the position of the measurement object, and shape information representing the shape of the measurement object by this coordinate information;
A moving means having a predetermined coordinate axis and moving the magnetic field probe;
Coordinate conversion means for converting coordinates represented by the coordinate information of the measurement object stored in the storage means into coordinates of the measurement object on the predetermined coordinate axis;
Magnetic field output means for outputting the intensity of the magnetic field based on a signal generated by the magnetic field probe;
Control means for moving the magnetic field probe by the moving means to a plurality of measurement positions where the distance from the surface of the measurement object is constant based on the shape information stored in the storage means;
An information output means for outputting magnetic field information representing the intensity of the magnetic field output by the magnetic field output means at each measurement position.

Further, the present invention is a circuit forming substrate having an electronic circuit formed by including the electronic component and wiring, the measurement object,
The storage means stores coordinate information representing coordinates indicating the positions of the electronic component and the wiring, shape information representing the shape of the electronic component and the wiring, and route information representing a connection path of the electronic component and the wiring,
Instruction means for instructing any of the connection routes represented by the route information;
Based on the shape arrangement information and the path information, including a region extraction unit that extracts a part including the wiring included in the transmission path instructed by the instruction unit, as a measurement region, out of the entire region of the circuit formation substrate,
The control means moves the magnetic field probe by the moving means so that the magnetic field probe faces the measurement area extracted by the area extraction means.

  In the invention, it is preferable that the information output means outputs graphic information representing the shape information of the measurement object and the magnetic field information as a graphic.

The present invention is also a current measuring device including the magnetic field measuring device,
The measurement object has a substrate including a wiring and a ground layer,
The shape information includes shape arrangement information representing the shape and arrangement position of the wiring and the ground layer,
Distance calculation for calculating a distance in a predetermined direction between the magnetic field probe arranged at the measurement position and the wiring and a distance between the wiring in the predetermined direction and the ground layer based on the shape information stored in the storage unit Means,
A current measurement device comprising: a current calculation unit that calculates a current value of a current flowing through the wiring based on the distance calculated by the distance calculation unit and the intensity of the magnetic field output by the magnetic field output unit. is there.

Further, the present invention is an electric field measuring device for measuring an electric field around a measurement object,
An electric field probe that generates a signal corresponding to the change in the electric field based on the change in the electric field;
Storage means for storing coordinate information representing coordinates indicating the position of the measurement object, and shape information representing the shape of the measurement object by this coordinate information;
A moving means having a predetermined coordinate axis and moving the electric field probe;
Coordinate conversion means for converting coordinates represented by the coordinate information of the measurement object stored in the storage means into coordinates of the measurement object on the predetermined coordinate axis;
Electric field output means for outputting electric field strength based on a signal generated by the electric field probe;
Control means for moving the electric field probe by the moving means to a plurality of measurement positions where the distance from the surface of the measurement object is constant based on the shape information stored in the storage means;
And an information output unit that outputs electric field information representing the intensity of the electric field output by the electric field output unit at each measurement position.

Further, the present invention is a circuit forming substrate having an electronic circuit formed by including the electronic component and wiring, the measurement object,
The storage means stores coordinate information representing coordinates indicating the positions of the electronic component and the wiring, shape information representing the shape of the electronic component and the wiring, and route information representing a connection path of the electronic component and the wiring,
Instruction means for instructing any of the connection routes represented by the route information;
Based on the shape arrangement information and the path information, including a region extraction unit that extracts a part including the wiring included in the transmission path instructed by the instruction unit, as a measurement region, out of the entire region of the circuit formation substrate,
The control means moves the electric field probe by the moving means so that the electric field probe faces the measurement region extracted by the area extraction means.

  In the invention, it is preferable that the information output means is a blank for outputting graphic information representing the shape information of the measurement object and the electric field information in a graphic form.

  According to the present invention, the coordinate conversion means converts the coordinates represented by the coordinate information of the measurement object stored in the storage means into the coordinates of the measurement object on the predetermined coordinate axis of the movement means, thereby measuring the magnetic field probe and the measurement object. Even without actually measuring the distance to the object, based on the coordinates represented by the coordinate information stored in the storage means by the control means, a plurality of measurement positions where the distance from the surface of the measurement object is constant, The distance between the actual magnetic field probe and the measurement object can be made constant at a plurality of measurement positions simply by moving the electric field probe by the moving means.

  Based on the signal generated by the magnetic field probe, the magnetic field output means can output the strength of the magnetic field, and magnetic field information indicating the strength of the magnetic field output by the magnetic field output means is output by the information output means. The user can accurately know the intensity of the magnetic field at each measurement position, that is, the distribution of the magnetic field around the measurement object. By taking countermeasures against electromagnetic interference using the obtained magnetic field information, electromagnetic interference can be effectively reduced.

  Further, by keeping the distance between the magnetic field probe and the measurement object constant, it is possible to accurately measure the distribution of the magnetic field that becomes an electromagnetic interference wave even when the measurement object is not flat. Furthermore, since a device such as a laser displacement meter that is necessary for detecting the distance to the measurement object is not required, the magnetic field probe can be miniaturized, and the magnetic field probe can be brought close to the measurement object to perform high-resolution measurement. It becomes possible. Further, only the magnetic field probe is close to the measurement object, and invasive problems can be minimized.

  Further, according to the present invention, when any one of the connection paths represented by the path information is instructed by the instruction unit, the area extraction unit is included in the transmission path instructed by the instruction unit among all the regions of the circuit formation substrate. The measurement area containing the wiring to be extracted is extracted. The control means moves the magnetic field probe by the moving means so as to face the measurement area extracted by the area extracting means, and causes the magnetic field output means to measure the magnetic field strength at a plurality of measurement positions. The user can selectively measure the area to be measured around the test object by indicating the connection path to be measured by the instruction means, thereby shortening the measurement time for measuring the magnetic field strength. can do.

  According to the invention, the information output means outputs graphic information representing the shape information of the measurement object and the magnetic field information as a graphic. Since the shape information of the measurement object and the magnetic field information are represented as graphics, the user can clearly grasp the magnetic field intensity distribution around the measurement object simply by looking at the graphics. Therefore, it becomes easy to grasp the part that is the source of the electromagnetic interference wave in the measurement object.

  Further, according to the present invention, the shape information includes shape arrangement information representing the shapes and arrangement positions of the wiring and the ground layer. The distance calculation means can calculate distance information representing the distance between the magnetic field probe and the wiring at the measurement position and the distance between the wiring and the ground layer based on the shape information stored in the storage means. The current calculation means obtains the current value of the current flowing through the wiring based on the distance information and the magnetic field strength information.

  Thus, the current flowing through the wiring can be obtained based on the detected magnetic field without directly detecting the current flowing through the wiring. For example, the current flowing through the wiring of the substrate on which the electronic circuit is formed is weak and the electronic components are densely mounted, so that it is difficult to directly detect the current flowing through the wiring. Even in such a case, the current can be obtained.

  According to the present invention, the coordinate conversion means converts the coordinates represented by the coordinate information of the measurement object stored in the storage means into the coordinates of the measurement object on the predetermined coordinate axis of the movement means, thereby measuring the electric field probe and the measurement. Even without actually measuring the distance to the object, based on the coordinates represented by the coordinate information stored in the storage means by the control means, a plurality of measurement positions where the distance from the surface of the measurement object is constant, The distance between the actual electric field probe and the measurement object can be made constant at a plurality of measurement positions simply by moving the electric field probe by the moving means.

  Based on the signal generated by the electric field probe, the electric field output means can output the intensity of the electric field, and the electric field information indicating the intensity of the electric field output by the electric field output means is output by the information output means. The user can accurately know the intensity of the electric field at each measurement position, that is, the distribution of the electric field around the measurement object. By taking countermeasures against electromagnetic interference using the obtained electric field information, electromagnetic interference can be effectively reduced.

  Further, by keeping the distance between the electric field probe and the measurement object constant, it is possible to accurately measure the distribution of the electric field that becomes an electromagnetic interference wave even when the measurement object is not a plane. Furthermore, since a device such as a laser displacement meter necessary for detecting the distance to the object to be measured is not required, the electric field probe can be miniaturized, and the electric field probe can be brought close to the object to be measured for high resolution measurement. It becomes possible. Further, only the electric field probe is close to the measurement object, and invasive problems can be minimized.

  Further, according to the present invention, when any one of the connection paths represented by the path information is instructed by the instruction unit, the area extraction unit is included in the transmission path instructed by the instruction unit among all the regions of the circuit formation substrate. A measurement area including a part including the wiring to be extracted is extracted. The control means moves the electric field probe by the moving means so as to face the measurement region extracted by the area extracting means, and causes the electric field measuring means to measure the electric field strength at a plurality of measurement positions. The user can selectively measure the area to be measured around the test object by indicating the connection path to be measured by the instruction means, thereby reducing the measurement time for measuring the electric field strength. can do.

  According to the invention, the information output means outputs graphic information representing the shape information of the measurement object and the electric field information as a graphic. Since the shape information of the measurement object and the electric field information are represented as graphics, the user can clearly grasp the intensity distribution of the electric field around the measurement object simply by looking at the graphics. Therefore, it becomes easy to grasp the part that is the source of the electromagnetic interference wave in the measurement object.

  FIG. 1 is a functional block diagram illustrating a configuration of a magnetic field measuring apparatus 10 according to an embodiment of the present invention, and FIG. 2 is a perspective view illustrating a moving unit 13 of the magnetic field measuring apparatus 10. The magnetic field measuring apparatus 10 includes a magnetic field probe 11, a CAD (Computer Aided Design) data storage unit 12 serving as a storage unit, a moving unit 13 serving as a moving unit, an alignment unit 14 serving as a coordinate conversion unit, and a magnetic field output unit. And an electromagnetic field measuring instrument 15, a Z coordinate calculation unit 16, a magnetic field measurement data storage unit 17, a measurement position control unit 18 as a control unit, and a display unit 19 as an information output unit. .

  The magnetic field measuring apparatus 10 is used for measuring a near magnetic field around the measurement object 21. In this embodiment, the measurement of the magnetic field is measurement of the strength of the magnetic field. In the present embodiment, the measurement object 21 is a circuit forming substrate in which an electronic circuit 24 formed including an electronic component 22 and a wiring 23 is provided on a substrate 25.

  The magnetic field probe 11 is formed including a loop-shaped antenna 31. The magnetic field probe 11 generates a signal corresponding to the change in the magnetic field based on the change in the magnetic field. When the magnetic field changes, an induced electromotive force that is induced by the change of the magnetic field is generated in the loop-shaped antenna 31. A signal based on the induced electromotive force, that is, a current flowing through the loop-shaped antenna 31 by the induced electromotive force is applied from the magnetic field probe 11 to the magnetic field measuring device 15.

  The CAD data storage unit 12 stores coordinate information representing coordinates indicating the position of the measurement object 21 and shape information representing the shape of the measurement object based on the coordinate information. The coordinate information and shape information are represented by CAD data for printed circuit board design. CAD data includes information on the shape of the substrate 25 represented by coordinate information, geometrical arrangement information of the electronic components 22 and wirings 23 mounted on the substrate 25, and terminal pins 33 of the electronic components 22 called netlists. Connection state information representing the connection state of the.

  The geometric arrangement information includes electronic component related information regarding the electronic component 22 and wiring related information regarding the wiring 23.

  The electronic component related information includes electronic component shape information indicating the shape of the electronic component 22, electronic component arrangement information indicating coordinates where the electronic component 22 is arranged, and the position and name of the terminal pin 33 that is a connection terminal of the electronic component 22. Contains pin information to represent. The shape information of the electronic component 22 represents the size of the electronic component 22 and the height from the one surface 32 of the substrate 25.

  The wiring related information includes shape information representing the shape of the wiring 23, wiring placement information representing the coordinates where the wiring 23 is placed, and net name information representing the name of the net in which each wiring 23 is included.

  The connection state information is shown in Tables 1 and 2. The connection state information is route information representing the route connection route of the wiring 23, and includes net name information, connection component information representing the electronic component 22 connected to the net represented by the net name information, and the electronic component 22. Connection terminal information representing the connected terminal pin 33 and internal connection state information representing the internal connection state of the electronic component are included. Table 1 shows net name information, connection component information, and connection terminal information. The terminal pin may be simply referred to as a pin.

  For example, the first net (net1) includes a first pin of a first electronic component and a second pin of a second electronic component.

  The signal group represents a transmission path of the same signal. For example, as shown in Table 2, the first pin and the eighth pin included in the first group are electrically inside the first electronic component. Indicates that it is connected.

  The moving unit 13 has a predetermined coordinate axis, and moves the magnetic field probe 11 based on an operation command given from the measurement position control unit 18. The moving unit 13 is realized by an orthogonal three-axis robot. Three predetermined coordinate axes of the moving unit 13 are defined as an X axis, a Y axis, and a Z axis, respectively. The moving unit 13 has a mounting table 34 on which the measurement object 11 is mounted. The mounting surface 35 of the mounting table 34 is formed by a plane perpendicular to the Z axis. The measurement object 11 has the electronic component 22 mounted only on one surface in the thickness direction of the substrate 25, and the other surface in the thickness direction of the substrate 25 is formed in a substantially flat surface. The measurement object 11 is placed on the placement table 34 such that the other surface in the thickness direction of the substrate 25 faces the placement surface 35. Therefore, the thickness direction of the substrate 11 is parallel to the Z axis. The mounting table 34 is provided with a locking portion 36 that detachably locks the measurement object 11 at a predetermined position on the mounting surface 35. The measurement object 11 is placed on the placement surface 35 of the placement table 34 and is locked by the locking portion 36. This prevents the measurement object 11 from moving undesirably during measurement. The substrate 25 has a rectangular plate shape. Here, each side of the peripheral portion of one surface of the substrate 25 is placed so as to extend in parallel with the X-axis direction or the Y-axis direction.

  The alignment unit 14 converts the coordinates represented by the coordinate information of the measurement object 21 stored in the CAD data storage unit 12 into the coordinates of the measurement object 21 on the predetermined coordinate axis. That is, the coordinate system of the coordinates represented by the coordinate information of the measurement object 21 stored in the CAD data storage unit 12 is converted into the coordinate system of the predetermined coordinate axes. As a result, the measurement position control unit 18 determines the coordinates of the magnetic field probe 11 based on the coordinate information of the measurement object 21 stored in the CAD data storage unit 12, so that the measurement object 21 on this data and The relative position with respect to the magnetic field probe 11 can be reflected in the actual relative position between the magnetic field probe 11 and the measurement object 21 in a predetermined coordinate space.

  The alignment unit 14 includes a camera unit 38 and a coordinate conversion unit. The camera unit 38 is provided on one side of the mounting table 34 in the Z-axis direction so as to image the mounting surface 35 of the mounting table 34. The camera unit 38 images the measurement object 21 placed on the placement table 34. Based on the image information obtained by the camera unit 38, the coordinate conversion unit converts the coordinates represented by the coordinate information of the measurement object 21 stored in the CAD data storage unit 12 into coordinates on a predetermined coordinate axis. The coordinates represented by the coordinate information of the measurement object 21 stored in the CAD data storage unit 12 are in a coordinate system that is determined in advance when CAD data is created. The coordinate conversion unit converts the coordinates represented by the coordinate information of the predetermined coordinate system when creating the CAD data into the coordinates of the coordinate system of the predetermined coordinate axis of the moving unit 13. The coordinate conversion unit converts the coordinates by, for example, rotation, enlargement, and reduction.

  The electromagnetic field measuring instrument 15 is realized by a spectrum analyzer used for frequency measurement. The electromagnetic field measuring device 15 is given a signal generated by the magnetic field probe 11 and outputs the strength of the magnetic field based on this signal. The electromagnetic field measuring device 15 outputs the intensity of electromagnetic waves in a predetermined frequency band, that is, the intensity of the magnetic field. Specifically, the electromagnetic field measuring device 15 outputs magnetic field strength information representing the strength of the magnetic field. The magnetic field strength information output by the electromagnetic field measuring device 15 is given to the magnetic field measurement data storage unit 17.

  The Z-axis coordinate calculation unit 16 reads CAD data from the CAD data storage unit 12 based on the operation command given from the measurement position control unit 18, and based on the read CAD data, the measurement position on the XY plane determined in advance. 2, the Z-axis coordinates are calculated such that the distance between the magnetic field probe 11 and one surface of the measurement object 21 is a predetermined distance T1.

The magnetic field measurement data storage unit 17, based on a command given from the measurement position control unit 18, measurement position information indicating the coordinates of each measurement position where the strength of the magnetic field is measured by the electromagnetic field measuring device 14, and the measurement position information at each measurement position. Magnetic field measurement data including magnetic field strength information representing the strength of the magnetic field is stored.
Table 3 shows the magnetic field measurement data stored in the measurement data storage unit 17.

  The display unit 19 outputs magnetic field measurement information representing magnetic field measurement data representing the strength of the magnetic field at each measurement position given from the magnetic field measurement data storage unit 17. The display unit 19 is realized by a liquid crystal display device, for example. The display unit 19 displays measurement position information that represents the coordinates of each measurement position and magnetic field strength information that represents the strength of the magnetic field at each measurement position. As a result, the user can know the intensity of the magnetic field around the measurement object 21.

  The measurement position control unit 18 is realized by a microcomputer, for example, and controls the moving unit 13 to move the magnetic field probe 11 to a predetermined measurement position. The measurement position control unit 18 sets a predetermined measurement range 40 based on CAD data. The predetermined measurement range 40 represents a range where the measurement object 11 exists on the X axis and the Y axis. The measurement position control unit 18 sets the XY trace path 41 within the predetermined measurement range. The XY trace path 41 is a path along which the magnetic field probe 11 moves as viewed from the one surface 32 side of the substrate 25. The measurement position control unit 18 sets the X coordinate and the Y coordinate of the plurality of measurement positions so that the predetermined measurement pitch is obtained in the XY trace path 41. That is, the interval Tx in the X-axis direction and the interval Ty in the Y-axis direction between adjacent measurement positions are selected equally. The predetermined measurement pitch depends on the resolution of the magnetic field probe 11, and when the resolution of the magnetic field probe 11 is low, the measurement pitch is selected to be larger than that with high resolution.

  FIG. 3 is a plan view showing a predetermined measurement range 40 and an XY trace path 41 set by the measurement position control unit 18, and FIG. 4 is a cross-sectional view taken along section line IV-IV in FIG. 3 and 4, each measurement position is indicated by a white circle (◯).

  When the measurement position control unit 18 sets the X-axis coordinates and the Y-axis coordinates of the plurality of measurement positions on the XY trace path 41, the coordinate information indicating the X-axis coordinates and the Y-axis coordinates of the measurement positions is obtained. This is given to the Z coordinate calculation unit 15 to cause the Z coordinate calculation unit 15 to calculate the X axis coordinate of the measurement position and the Z axis coordinate of the position corresponding to the Y axis coordinate. The Z coordinate calculation unit 15 refers to the CAD data based on the coordinate information given from the measurement position control unit 18 and confirms the presence or absence of the electronic component 22 at the measurement position. When the electronic component 22 exists at the measurement position, the Z-axis coordinate calculation unit 15 obtains the height of the electronic component 22 registered as a CAD data component library at the measurement position, and calculates the magnetic field probe 11 and the measurement target. The Z-axis coordinates are calculated such that the distance between the object 21 and the object 21 is a constant distance T1 in the Z-axis direction. When the electronic component 22 does not exist at the measurement position, the Z-axis coordinate calculation unit 15 obtains the distance from the one surface 32 of the substrate 25, and the magnetic field probe 11 and the measurement object 21 are constant in the Z-axis direction. The coordinates of the Z axis are calculated so as to be the distance T1.

  The Z coordinate calculation unit 15 gives coordinate information representing the Z-axis coordinates calculated at each measurement position to the measurement position control unit 18. The measurement position control unit 18 moves the magnetic field probe 11 along the XYZ trace path 42 shown in FIG. 4 based on the coordinate information representing the Z-axis coordinates of each measurement position given from the Z-axis coordinate calculation unit 15. Move to 13.

  The magnetic field probe 11 includes a loop-shaped antenna 31 and a housing 43 that houses the antenna 31. The loop-shaped antenna 31 has a substantially C-shaped loop portion and wiring portions respectively connected to both ends of the loop portion. Each wiring part is connected to the electromagnetic field measuring instrument 15.

  The container 43 is formed of a material that transmits electromagnetic waves, that is, formed of a material having a high magnetic permeability, and surrounds and protects the loop-shaped antenna 31. The coordinate position of the magnetic field probe 11 in a predetermined coordinate space is the center of the tip 44 of the magnetic field probe 11, in other words, the coordinate of the center of the tip of the container 43.

The coordinates of the X-axis of the magnetic field probe 11 and X _0, the coordinates of the Y-axis and Y _0, when the X-axis direction dimension of the magnetic field probe 11 and Wy dimensions Wx and Y-axis direction, XY plane of the magnetic field probe 11 external _shape, P ₁ in the _{(X 0 -Wx / 2, Y} 0 -Wy / 2), P 2 (X 0 + Wx / 2, Y 0 -Wy / 2), P 3 (X 0 + Wx / 2, Y 0 + Wy / 2) and 4 points of P ₄ (X ₀ −Wx / 2, Y ₀ + Wy / 2).

For example, when the magnetic field probe 11 is translated in the X-axis direction in the direction in which the coordinates are increased, whether or not the straight line connecting the coordinates P ₂ and P ₃ is in contact with the electronic component 22, that is, the coordinates P ₂ and coordinates included in a line connecting the P ₃ is, to determine whether or not entered a region occupied by the electronic components 22, and the magnetic field probe 11 and the electronic component 22 contacts, or between the magnetic field probe 11 and the electronic component 22 When the gap between the two is smaller than a predetermined clearance, the Z coordinate calculation unit 16 calculates the coordinate on the Z axis at the measurement position in consideration of the height of the electronic component 22.

  Thus, the measurement position control means 19 can move the magnetic field probe 11 to the plurality of measurement positions at which the distance from the surface of the measurement object 21 in the Z-axis direction is constant. The alignment unit 14 and the Z coordinate calculation unit 15 described above are realized by a microcomputer, for example.

  FIG. 5 is a cut end view of the electric field probe 11 as seen from the cut surface line V-V in FIG. 4. The measurement position control unit 18 controls the moving unit 13 so that the electric field probe 11 traces the XY trace path 41 on the XY plane twice. The measurement position control unit 18 controls the moving unit 13 so that the extending direction of the axis L1 of the loop portion of the loop-shaped antenna 31 of the magnetic field probe 11 differs by 90 degrees between the first measurement and the second measurement. To do. For example, in the first measurement, like the loop antenna 31a of the magnetic field probe 11a, the extending direction of the axis L1 is arranged in parallel to the X axis, and in the second measurement, the loop shape of the magnetic field probe 11b. Like the antenna 31b, the extending direction of the axis L1 is arranged parallel to the Y axis.

  The magnetic field measurement data storage unit 17 stores each electric field measurement data obtained in the first measurement and the second measurement, and an electric field measurement representing an average of the magnetic field strengths obtained in the first measurement and the second measurement. Data is stored. Electric field measurement information representing these three electric field measurement data is displayed on the display unit 19.

  As described above, in the magnetic field measurement apparatus 10, the CAD data is used to determine the distance between the magnetic field probe 11 and the measurement object 21 in advance without actually measuring the distance between the magnetic field probe 11 and the measurement object 21. The distance in the direction can be kept constant, whereby the magnetic field distribution of the electromagnetic interference wave can be accurately measured even when the surface of the measuring object 21 is not flat.

  Further, the magnetic field information displayed on the display unit 19 allows the user to accurately know the magnetic field intensity at each measurement position, that is, the magnetic field intensity distribution around the measurement object. By taking countermeasures against electromagnetic interference using the obtained magnetic field information, electromagnetic interference can be effectively reduced.

  Further, by keeping the distance between the magnetic field probe 11 and the measurement object 21 constant in a predetermined direction, the distribution of the magnetic field that becomes an electromagnetic interference wave can be accurately measured even when the measurement object 21 is not flat. Further, since it is not necessary to use a laser displacement meter as used in the second prior art for detecting the distance to the measurement object 21, the magnetic field probe 11 can be reduced in size, and the magnetic field probe 11 can be reduced. It is possible to perform measurement with high resolution in the vicinity of the measurement object 21. Further, only the magnetic field probe 11 is close to the measurement object 21, and the invasive problem can be minimized, and the measurement accuracy can be improved.

  FIG. 6 is a functional block diagram showing a configuration of a magnetic field measuring apparatus 50 according to another embodiment of the present invention. The magnetic field measurement device 50 has the same configuration as the magnetic field measurement device 10 shown in FIG. 1 described above, and includes a magnetic field probe 11, a CAD data storage unit 12 as storage means, a movement unit 13 as movement means, and coordinates. An alignment unit 14 as a conversion unit, an electromagnetic field measuring device 15 as a magnetic field output unit, a Z coordinate calculation unit 16, a magnetic field measurement data storage unit 17, a measurement position control unit 18 as a control unit, and an information output The display unit 19, which is a means, a measurement target net name storage unit 51, a measurement region calculation unit 52, a measurement region storage unit 53, and an instruction unit 54 are included. The magnetic field measurement apparatus 50 according to the present embodiment includes a measurement target net name storage unit 51, a measurement area calculation unit 52 that is a measurement area extraction unit, a measurement area storage unit 53, an instruction in the configuration of the magnetic field measurement apparatus 1 described above. Since it is the structure which added the instruction | indication part 54 which is a means, the same referential mark is attached | subjected to a corresponding part and the overlapping description may be abbreviate | omitted.

  The measurement target net name storage unit 51 stores measurement target net name information representing a net name to be measured. The measurement target net name storage unit 51 stores net name information representing a net that is a main cause of noise generation such as a clock line and is predicted to cause unnecessary electromagnetic radiation from the logic design, that is, the circuit design stage.

  The instruction unit 54 includes an operation key for inputting instruction information indicating any one of the connection paths represented by the path information, that is, any one of the net names representing the nets. The user can store the net name information representing the net name to be measured in the measurement target net name storage unit 51 by operating the operation key of the instruction unit 54.

  The measurement target net name storage unit 51 stores net name information representing the net name to be measured input by the instruction unit 54.

  The measurement area calculation unit 52 routes all wirings of the measurement target net from the net based on the measurement target net name stored in the measurement target net name storage unit 51 and the CAD data stored in the CAD data storage unit 12. Search, find the minimum and maximum values of the X-axis coordinates and Y-axis coordinates of the wiring, respectively, and the maximum and minimum values of the X-axis coordinates of the wiring and the minimum and maximum values of the Y-axis coordinates Then, the measurement area 51 is obtained from a predetermined offset value.

  The electronic component 22 includes, for example, a resistor, a capacitor, and a noise countermeasure component. Based on the connection state information shown in Tables 1 and 2 described above, the measurement region calculation unit 52 sets a net connected inside the electronic component 22 as one measurement target net. For example, referring to Table 1, the first net including the first pin of the first electronic component and the second net including the eighth pin of the first electronic component include the first pin and the eighth pin as shown in Table 2. Since the pins are connected internally, these first and second nets are taken as nets to be measured. The electronic component 22 such as a collective resistor (block resistor) has three or more terminal pins 33. As shown in Table 2, by adding group information indicating an internal connection state, three or more terminal pins 33 are provided. A plurality of nets including each terminal pin 33 of the electronic component 22 having the terminal pins 33 can be used as one measurement target net, and a single measurement target net can be used for a net separated by the electronic component 22. It can be.

  For example, assuming that the first net is stored in the measurement target net name storage unit 51 as the net name of the measurement target, the measurement region calculation unit 52 uses the connection state information shown in Tables 1 and 2 as described above. It is determined that the first net and the second net are connected by the first electronic component, and the measurement area 51 is obtained based on the wiring 23 included in the first net and the second net.

  The measurement area calculation unit 52 extracts a measurement target net based on the CAD data stored in the CAD data storage unit 12 and the measurement target net name stored in the measurement target net name storage unit 51. A measurement region 51 including the wiring 23 included in the net is extracted. The measurement area 51 is a part of the entire area of the substrate 25.

  FIG. 7 is a diagram for explaining how to obtain the measurement region 51. For example, it is assumed that the net name to be measured is the first net (net1), and the first electronic component IC1, the second electronic component IC2, and the third electronic component IC3 are connected to the first net. First, the measurement region calculation unit 52 searches for the wiring included in the first net, the first coordinate Pmin (Xmin, Ymin) representing the minimum value of the X-axis coordinate and the Y-axis coordinate, the X-axis coordinate, and A second coordinate Pmax (Xmax, Ymax) representing the maximum value of the Y-axis coordinates is obtained. And the measurement area | region 51 which provided the offset area | region in the outer peripheral part of the rectangular area 55 enclosed by the said 1st coordinate Pmin and the 2nd coordinate Pmax is calculated | required. The measurement area 51 includes a third coordinate Pdmin (Xmin-D, Ymin-D) obtained by subtracting the offset value D from each coordinate of the first coordinate Pmin, and a first coordinate value obtained by adding the offset value D to each coordinate of the second coordinate Pmax. This is a rectangular area surrounded by the four coordinates Pdmax.

  The measurement area 51 is selected to be rectangular. The wiring 23 may be bent between the terminal pins 33 of the electronic component 22 to be connected. However, by making the measurement area 51 rectangular, such a bent wiring can be measured. 51 can be included.

  The offset value D is determined in advance. The offset value D is determined based on the measurement frequency. The offset value D is determined by conducting an experiment, but is selected to be approximately 5 mm.

  The measurement region calculation unit 52 gives measurement region information representing the calculated measurement region 51 to the measurement region storage unit 53.

  The measurement area storage unit 53 stores measurement area information given from the measurement area calculation unit 52. The measurement target net name storage unit 51 and the measurement area information storage unit 53 are realized including a flash memory, for example.

  Based on the measurement area information stored in the measurement area storage unit 53, the measurement position control unit 18 sets the XY trace path 41 in the measurement area 51 represented by the measurement area information. The measurement position control unit 18 moves the magnetic field probe 11 by the moving unit 13 so that the magnetic field probe 11 faces the measurement region 51, and the X-axis coordinate and the Y-axis coordinate are within the measurement region 51. The electromagnetic field measuring instrument 15 is caused to measure the magnetic field only at the position.

  As described above, based on the net name instructed by the instruction unit 54, the measurement region calculation unit 52 includes the wiring included in the net instructed by the instruction unit 54 in the entire region of the measurement object 21. Region 51 is extracted. The measurement position control unit 18 moves the magnetic field probe 11 by the moving unit 13 in the measurement region 51 extracted by the measurement region calculation unit 52, and causes the electromagnetic field measuring device to measure the strength of the magnetic field at a plurality of measurement positions. The user can selectively measure the area to be measured in the periphery of the test object 21 by instructing the net to be measured by the instruction unit 54, and the measurement time for measuring the strength of the magnetic field. Can be shortened. In the magnetic field measuring apparatus 50, since the user can measure the minimum necessary area by designating the net name, the time for measuring the magnetic field can be shortened. Also, for example, based on the magnetic field measurement data obtained by designating a net that includes noise suppression components, the noise suppression components can be verified smoothly and the noise suppression components can be selected efficiently. become able to.

  Also, simply by specifying the net name, the net represented by this net name and the net connected via the electronic component are combined into one measurement target net, so that the wiring 23 through which a common signal is transmitted is provided. The area to be included can be measured together.

  FIG. 8 is a functional block diagram showing a configuration of a magnetic field measuring apparatus 60 according to still another embodiment of the present invention. The magnetic field measurement device 60 has the same configuration as the magnetic field measurement device 10 shown in FIG. 1 described above, and includes a magnetic field probe 11, a CAD data storage unit 12 as storage means, a movement unit 13 as movement means, and coordinates. An alignment unit 14 as a conversion unit, an electromagnetic field measuring device 15 as a magnetic field output unit, a Z coordinate calculation unit 16, a magnetic field measurement data storage unit 17, a measurement position control unit 18 as a control unit, and an information output The display unit 19 as a means, a line shape calculation unit 61, a line shape storage unit 62, a current calculation unit 63, and a current measurement data storage unit 64 are included. The magnetic field measurement apparatus 50 according to the present embodiment adds a line shape calculation unit 61, a line shape storage unit 62, a current calculation unit 63, and a current measurement data storage unit 64 to the configuration of the magnetic field measurement device 1 described above. Therefore, the corresponding parts may be denoted by the same reference numerals and redundant description may be omitted.

  In addition to the wiring 23, a ground layer 65 is provided on the substrate 25 of the measurement object 11. In addition to the shape information described above, the CAD data storage unit 12 stores ground layer information representing the shape and arrangement of the ground layer 65. The substrate 25 is formed by forming a wiring 23 and a ground layer 65 on a base 66 made of an insulating material.

FIG. 9 is a diagram for explaining the relationship between the current flowing in the microstrip line formed by the wiring 23 and the ground layer 65 and the magnetic field. The wiring 23 formed on the one surface 25 of the substrate 25 of the measurement object 11 constitutes a microstrip line together with the ground layer 65. The shortest distance from the loop center axis L1 of the loop-shaped antenna 31 of the magnetic field probe 11 at the measurement position to the center in the Z-axis direction of the wiring 23 to be measured for current is r, and the substrate 25 in the Z-axis direction is r. When the thickness of the base 66 from the wiring 23 to the ground layer 65 is h and the strength of the magnetic field at the measurement position is H, the mirror image current I with the ground layer 65 as a symmetry plane is expressed by the approximate expression (1). . In Equation 1, the circumference is π. The mirror image current I is a current flowing through the wiring 23.
I = π · r / h (r + 2h) H (1)

  The line shape calculation unit 11 is a distance calculation unit, and refers to the distance r from the magnetic field probe 11 to the wiring 23 formed on the surface layer of the substrate 25 and the CAD data stored in the CAD data storage unit 12. The distance r from the central axis L1 of the loop portion of the loop-shaped antenna 31 of the magnetic field probe 11 at the measurement position to the center of the wiring 23 whose current is to be measured in the Z-axis direction and the wiring 23 of the substrate 25 in the Z-axis direction. To the thickness h of the base 66 from the ground layer 65 to the ground layer 65. The shortest distance r from the central axis L1 of the loop portion of the loop-shaped antenna 31 of the magnetic field probe 11 at the measurement position to the center in the Z-axis direction of the wiring 23 whose current is to be measured is simply referred to as a distance r, and The thickness h of the base 66 from the wiring 23 of the substrate 25 to the ground layer 65 in the direction is simply referred to as the thickness h.

  The route shape calculation unit 61 provides the route shape storage unit 62 with distance information representing the distance r and thickness information representing the thickness h.

  The route shape storage unit 62 stores distance information and thickness information given from the route shape calculation unit 61. The route shape storage unit 62 includes, for example, a flash memory.

  The current calculation unit 63 is current calculation means, and is based on the magnetic field measurement data 17 stored in the electric field measurement data storage unit 17 and the distance information and thickness information stored in the route shape storage unit 62. The current value of the current flowing through is calculated. The current calculation unit 63 calculates the current flowing through the wiring 23 based on the above-described Expression 1. The current calculation unit 63 gives current measurement data representing the calculated current value to the current measurement data storage unit 64.

  The current measurement data storage unit 64 stores the current measurement data calculated by the current calculation unit 63.

  The display unit 19 displays the current value flowing through the wiring 23 represented by the current measurement data stored in the current measurement data storage unit 64.

  As described above, the magnetic field measurement device 60 can extract the shape of the microstrip line by using the magnetic field measurement data and the CAD data, and calculates the current flowing through the wiring 23 provided on the surface layer of the substrate 25. It becomes possible. The magnetic field measuring apparatus 60 can obtain the current flowing through the wiring 23 based on the detected magnetic field without directly detecting the current flowing through the wiring 23. Although the current flowing through the wiring 23 of the substrate 25 on which the electronic circuit 24 is formed is weak and it is difficult to directly detect the current flowing through the wiring 23, according to the present invention, even in such a case, The current value of the current flowing through the wiring 23 can be obtained.

  FIG. 10 is a functional block diagram showing a configuration of a magnetic field measuring apparatus 70 according to still another embodiment of the present invention. The magnetic field measurement device 70 has the same configuration as the magnetic field measurement device 10 shown in FIG. 1 described above, and includes a magnetic field probe 11, a CAD data storage unit 12 as storage means, a movement unit 13 as movement means, and coordinates. An alignment unit 14 as a conversion unit, an electromagnetic field measuring device 15 as a magnetic field output unit, a Z coordinate calculation unit 16, a magnetic field measurement data storage unit 17, a measurement position control unit 18 as a control unit, and an information output The display unit 19, the line shape calculation unit 61, the line shape storage unit 62, the current calculation unit 63, the current measurement data storage unit 64, the display data conversion unit 71, and the overlay display data storage unit, which are means. 72 and a CAD system 73. The magnetic field measurement device 70 of the present embodiment is configured by adding a display data conversion unit 71, a superimposed display data storage unit 72, and a CAD system 73 to the configuration of the magnetic field measurement device 60 described above. Corresponding portions are denoted by the same reference numerals, and redundant description may be omitted.

  The magnetic field measurement device 70 displays the shape information of the measurement object 21 and the magnetic field information indicating the intensity of the magnetic field around the measurement object 21 in a graphic form and displays them on the display unit 19.

  The display data conversion unit 71 has a data format in which the magnetic field measurement data stored in the magnetic field measurement data storage unit 17 and the current measurement data stored in the current measurement data storage unit 64 can be read and superimposed on CAD data. Convert to overlay display data. The overlay display data obtained by the display data conversion unit 71 is given to the overlay display measurement data storage unit 72.

  The overlay display measurement data storage unit 72 stores the overlay display data provided from the display data conversion unit 71. The superimposed display measurement data storage unit 72 is realized including a flash memory, for example.

  The CAD system 73 reads the CAD data and the overlay display data, and the display unit 19 adds the magnetic field information represented by the magnetic field measurement data or the current information represented by the current measurement data to the shape information represented by the CAD data of the measurement object 21. Graphic information representing the superimposed graphic is displayed. The shape information of the measurement object 21 and the information indicating the magnetic field strength and current value at each measurement position are represented as figures.

  FIG. 11 is a diagram showing a display screen 74 in which shape information based on CAD data and magnetic field information represented by magnetic field measurement data are superimposed on the display unit 19 and displayed. The shape information is represented by a plan view of the measuring object 11 viewed from one side in the Z-axis direction. On the display screen 74, a graphic representing the measurement object 21 is displayed. The graphic representing the measurement object 21 includes a graphic representing the electronic component 22 and the wiring 23.

  In addition, the display screen 74 displays isomagnetic field lines that connect measurement positions that have a predetermined range of magnetic field strength among the measurement positions.

  Table 4 shows the types of lines connecting the predetermined magnetic field strength H range and the measurement positions at which the magnetic field strength included in the predetermined magnetic field strength H range. A line connecting measurement positions, which are predetermined magnetic field strengths, is referred to as an isomagnetic field line.

  For example, the measurement position where the magnetic field strength H is 96 dBμA / m or more and less than 102 dBμA / m is connected by a thin two-dot chain line. As shown in FIG. 11, the display unit 19 displays a magnetic field line representing a magnetic field together with a graphic representing the shape of the measurement object 21.

  As described above, in the magnetic field measuring device 70, the shape information based on the CAD data and the information indicating the strength of the magnetic field are displayed as graphic information on the display unit 19, so that the user can display the graphic information displayed on the display unit 19. It is possible to clearly grasp the magnetic field intensity distribution around the measurement object 21 simply by looking at the figure represented by. Therefore, in the measurement object 21, it becomes easy to grasp the part that is the source of electromagnetic interference.

  In addition, the magnetic field measuring device 70 is configured to display the shape information of the measurement object 21 and the current in the same manner as displaying the shape information of the measurement object 21 and the magnetic field information on the display unit 19 as a graphic as shown in FIG. The current information based on the measurement data can be displayed on the display unit 19 as a graphic. Therefore, the user can clearly grasp the value of the current flowing through the wiring 23 of the measuring object 21 only by looking at the graphic displayed on the display unit 19.

  FIG. 12 is a functional block diagram showing a configuration of the electric field measurement apparatus 80 according to the embodiment of the present invention. The electric field measuring apparatus 80 includes an electric field probe 81, a CAD data storage unit 12 as a storage unit, a moving unit 13 as a moving unit, an alignment unit 14 as a coordinate conversion unit, and an electromagnetic field measurement as an electric field output unit. The device 15 includes a Z coordinate calculation unit 16, an electric field measurement data storage unit 82, a measurement position control unit 18 serving as a control unit, and a display unit 19 serving as an information output unit. The electric field measuring device 80 is used for measuring a near magnetic field around the measurement object 21.

  The magnetic field measurement device 80 has a configuration in which the magnetic field probe 11 in the magnetic field measurement device 10 of the embodiment shown in FIG. 1 is replaced with an electric field probe 81, and the magnetic field measurement data storage unit 17 is replaced with an electric field measurement data storage unit 82. Since other configurations are the same as those of the magnetic field measuring apparatus 10, the same reference numerals are given to the same parts, and the description thereof may be omitted.

  The electric field probe 81 includes three minute pole antennas whose axes are orthogonal to each other. The electric field probe 81 has a configuration in which the loop antenna 31 in the magnetic field probe 11 is replaced with a minute pole antenna. In the electric field probe 81, a voltage is generated in the three minute dipole antennas based on the electric field. The electromagnetic field measuring device 15 detects the voltage generated in the minute dipole antenna with a diode, and detects the DC voltage detected by the diode with a resistor, thereby outputting the electric field strength in a predetermined frequency band.

  The electric field measurement data storage unit 82 stores electric field measurement data representing the intensity of the electric field output by the electric field measuring device 15 based on the measurement position and the signal generated by the electric field probe 81 at the measurement position. The display unit 19 displays information representing each measurement position and electric field information representing the intensity of the electric field at the measurement position based on the electric field measurement data stored in the electric field measurement data storage unit 82.

  In the electric field measuring device 80, even if the distance between the electric field probe 81 and the measurement object 21 is not actually measured, the distance between the electric field probe 81 and the measurement object 21 in a predetermined direction can be determined by using CAD data. Thus, even when the surface of the measuring object 21 is not flat, the magnetic field distribution of the electromagnetic interference wave can be accurately measured.

  Further, the electric field information displayed on the display unit 19 allows the user to accurately know the intensity of the electric field at each measurement position, that is, the distribution of the electric field around the measurement object. By taking countermeasures against electromagnetic interference using the obtained electric field information, the electric field interference can be effectively reduced.

  In addition, by keeping the distance between the electric field probe 81 and the measurement object 21 constant in a predetermined direction, the distribution of the electric field that becomes an electromagnetic interference wave can be accurately measured even when the measurement object 21 is not flat. Further, since it is not necessary to use a laser displacement meter as used in the second prior art for detecting the distance to the measurement object 21, the electric field probe 81 can be reduced in size. It is possible to perform measurement with high resolution in the vicinity of the measurement object 21. In addition, the electric field measuring device 80 can measure a near electric field, and can easily detect an electromagnetic interference generated by resonance between the wiring 23 and the ground layer 65.

  In the electric field measuring apparatus according to another embodiment of the present invention, the magnetic field probe 11 in the magnetic field measuring apparatus 50 according to the above-described embodiment shown in FIG. 6 is replaced with the electric field probe 81, and the magnetic field measurement data storage unit 17 is measured with the electric field. The data storage unit 82 may be replaced. Also in this case, the same effect as that of the magnetic field measuring apparatus 50 can be obtained in measuring the electric field.

  FIG. 13 is a block diagram showing an electric field measuring apparatus 90 according to still another embodiment of the present invention. In addition to the configuration of the electric field measurement device 80 shown in FIG. 12 described above, the electric field measurement device 90 of the present embodiment includes a display data conversion unit 91, an overlay display measurement data storage unit 92, and an electric field CAD system 93. The same reference numerals are given to the same components as those of the electric field measuring apparatus 80 of the above-described embodiment, and the description thereof is omitted.

  The display data conversion unit 91 reads the electric field measurement data stored in the electric field measurement data storage unit 82, and converts it into overlay display data that is a data format that can be displayed superimposed on CAD data. The overlay display data obtained by the electric field display data conversion unit 91 is provided to the electric field overlay display measurement data storage unit 92.

  The electric field overlay display measurement data storage unit 92 stores overlay display data provided from the display data conversion unit 91. The superimposed display measurement data storage unit 93 is realized including a flash memory, for example.

  The CAD system 93 reads the CAD data and the overlay display data, and causes the display unit 19 to display the electric field information represented by the electric field measurement data superimposed on the shape information based on the CAD data of the measurement target 21.

  As described above, the electric field measurement device 90 displays the shape information of the measurement object 21 and the information indicating the intensity of the electric field as a graphic, so that the user only needs to look at the graphic, The intensity distribution of the electric field can be clearly grasped. Therefore, in the measurement object 21, it becomes easy to grasp the part that is the source of electromagnetic interference.

  In still another embodiment of the present invention, an apparatus may be configured by combining the magnetic field measurement apparatus and the electric field measurement apparatus of the above-described embodiments. For example, an electromagnetic wave that can measure a magnetic field and an electric field at a measurement position A field measuring device may be configured. Further, the moving unit 13 described above is not limited to an orthogonal three-axis robot, but may be an arm type robot or any structure that can move the magnetic field probe 11 in a three-dimensional space.

  In still another embodiment of the present invention, in the magnetic field measurement apparatus 70 according to the above-described embodiment, the display unit 19 superimposes shape information based on CAD data and information represented by the magnetic field measurement data to 3 It may be displayed as a dimensional figure.

  In still another embodiment of the present invention, in the magnetic field measurement apparatus 90 according to the above-described embodiment, the display unit 19 superimposes shape information based on CAD data and information represented by electric field measurement data, You may display as a three-dimensional figure.

It is a functional block diagram which shows the structure of the magnetic field measuring apparatus 10 of implementation of this invention. 3 is a perspective view showing a moving unit 13 of the magnetic field measuring apparatus 10. FIG. 4 is a plan view showing a predetermined measurement range 40 and a trace path 41 set by the measurement position control unit 18. FIG. FIG. 4 is a cross-sectional view taken along section line IV-IV in FIG. 3. FIG. 5 is a cut end view of the electric field probe 11 as seen from the cut line VV of FIG. 4. It is a functional block diagram which shows the structure of the magnetic field measuring apparatus 50 of other embodiment of this invention. It is a figure for demonstrating how to obtain | require the measurement area | region 51. FIG. It is a functional block diagram which shows the structure of the magnetic field measuring apparatus 60 of further another embodiment of this invention. It is a figure explaining the relationship between the electric current which flows into the microstrip line formed of the wiring 23 and the ground layer 65, and a magnetic field. It is a functional block diagram which shows the structure of the magnetic field measuring apparatus 70 of further another embodiment of this invention. It is a figure which shows the display screen 74 which displayed on the display part 19 the shape information based on CAD data, and the magnetic field information which magnetic field measurement data represent in a superimposed manner. It is a functional block diagram which shows the structure of the electric field measuring apparatus 80 of one Embodiment of this invention. It is a block diagram which shows the electric field measuring apparatus 90 of the form of further another embodiment of this invention. It is a perspective view which shows the electromagnetic interference measuring apparatus 1 of the 1st prior art which measures the intensity | strength of the electromagnetic waves which generate | occur | produce from an electronic device. It is a figure which expands and shows the near magnetic field probe 7 in the electromagnetic interference wave measuring apparatus of the 2nd prior art which measures the intensity | strength of the electromagnetic waves which generate | occur | produce from an electronic device, and its vicinity.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 50, 60, 70 Magnetic field measuring device 11 Magnetic field probe 12 CAD data memory | storage part 13 Moving part 14 Positioning part 15 Electromagnetic field measuring device 16 Z coordinate calculation part 17 Magnetic field measurement data memory | storage part 18 Measurement position control part 19 Display part 80 , 90 Electric field measuring device 81 Electric field probe 82 Electric field measurement data storage unit

Claims (7)

A magnetic field measuring apparatus for measuring a magnetic field around a measurement object,
A magnetic field probe that generates a signal corresponding to the change in the magnetic field based on the change in the magnetic field;
Storage means for storing coordinate information representing coordinates indicating the position of the measurement object, and shape information representing the shape of the measurement object by this coordinate information;
A moving means having a predetermined coordinate axis and moving the magnetic field probe;
Coordinate conversion means for converting coordinates represented by the coordinate information of the measurement object stored in the storage means into coordinates of the measurement object on the predetermined coordinate axis;
Magnetic field output means for outputting the intensity of the magnetic field based on a signal generated by the magnetic field probe;
Control means for moving the magnetic field probe by the moving means to a plurality of measurement positions where the distance from the surface of the measurement object is constant based on the shape information stored in the storage means;
An information output means for outputting magnetic field information representing the intensity of the magnetic field output by the magnetic field output means at each measurement position. The measurement object is a circuit forming substrate having an electronic circuit formed including electronic components and wiring,
The storage means stores coordinate information representing coordinates indicating the positions of the electronic component and the wiring, shape information representing the shape of the electronic component and the wiring, and route information representing a connection path of the electronic component and the wiring,
Instruction means for instructing any of the connection routes represented by the route information;
Based on the shape arrangement information and the path information, including a region extraction unit that extracts a part including the wiring included in the transmission path instructed by the instruction unit, as a measurement region, out of the entire region of the circuit formation substrate,
2. The magnetic field measuring apparatus according to claim 1, wherein the control means moves the magnetic field probe by the moving means so that the magnetic field probe faces the measurement area extracted by the area extracting means.   3. The magnetic field measuring apparatus according to claim 1, wherein the information output unit outputs graphic information representing the shape information of the measurement object and the magnetic field information as a graphic. A current measuring device including the magnetic field measuring device according to claim 1,
The measurement object has a substrate including a wiring and a ground layer,
The shape information includes shape arrangement information representing the shape and arrangement position of the wiring and the ground layer,
Distance calculation for calculating a distance in a predetermined direction between the magnetic field probe arranged at the measurement position and the wiring and a distance between the wiring in the predetermined direction and the ground layer based on the shape information stored in the storage unit Means,
A current measuring apparatus comprising: a current calculating unit that calculates a current value of a current flowing through the wiring based on a distance calculated by the distance calculating unit and a magnetic field intensity output by the magnetic field output unit. An electric field measuring device for measuring an electric field around a measurement object,
An electric field probe that generates a signal corresponding to the change in the electric field based on the change in the electric field;
Storage means for storing coordinate information representing coordinates indicating the position of the measurement object, and shape information representing the shape of the measurement object by this coordinate information;
A moving means having a predetermined coordinate axis and moving the electric field probe;
Coordinate conversion means for converting coordinates represented by the coordinate information of the measurement object stored in the storage means into coordinates of the measurement object on the predetermined coordinate axis;
Electric field output means for outputting electric field strength based on a signal generated by the electric field probe;
Control means for moving the electric field probe by the moving means to a plurality of measurement positions where the distance from the surface of the measurement object is constant based on the shape information stored in the storage means;
An electric field measurement apparatus comprising: information output means for outputting electric field information representing the intensity of the electric field output by the electric field output means at each measurement position. The measurement object is a circuit forming substrate having an electronic circuit formed including electronic components and wiring,
The storage means stores coordinate information representing coordinates indicating the positions of the electronic component and the wiring, shape information representing the shape of the electronic component and the wiring, and route information representing a connection path of the electronic component and the wiring,
Instruction means for instructing any of the connection routes represented by the route information;
Based on the shape arrangement information and the path information, including a region extraction unit that extracts a part including the wiring included in the transmission path instructed by the instruction unit, as a measurement region, out of the entire region of the circuit formation substrate,
6. The electric field measuring apparatus according to claim 5, wherein the control means moves the electric field probe by the moving means so that the electric field probe faces the measurement region extracted by the area extracting means.   7. The electric field measuring apparatus according to claim 5, wherein the information output means is a blank for outputting graphic information representing the shape information of the measurement object and the electric field information as a graphic.

Images