JP2019211297A - System and method for specifying noise immunity vulnerable point on circuit board - Google Patents

Abstract

To provide a system and method for specifying a noise immunity vulnerable point, with which it is possible to easily specify a noise immunity vulnerable point on a circuit board by a simple configuration, as well as monitor the state of the circuit board before a false operation occurs.SOLUTION: An FG 3 generates a GSM signal as noise and applies it to a probe 4. The probe 4 is scanned by a probe scanning device 5, and applies noise to multiple points on a circuit board 2. An electronic component 7 on the circuit board 2 has a speaker 8 connected thereto via a signal line 9. An SPA 11 is connected to the signal line 9, and a PC 6 is connected to the SPA 11. The PC 6 constitutes a comparison device and an analysis device. The comparison device compares the noise level of measured noise with the permissible level of noise permitted for the signal line 9. The analysis device specifies a noise immunity vulnerable point on the circuit board 2 on the basis of a plurality of comparison results obtained by the comparison device with regard to multiple points on the circuit board 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a noise resistant weak spot specifying system and a noise resistant weak spot specifying method for specifying a noise resistant weak spot on a circuit board.

  Conventionally, as this type of system and method for specifying a noise-resistant weak spot on a circuit board, for example, there is a malfunction spot identification method and a malfunction spot identification system disclosed in Patent Document 1.

  In this malfunction location identification method and system, the probe is scanned by the position controller, and radiation noise is applied from the probe to a plurality of preset points on the circuit board, and second conduction noise is injected into the circuit board. . The personal computer acquires the output signal of the gyro sensor on the circuit board as a CAN signal through the microcomputer, and determines whether there is a malfunction. The determination of whether or not there is a malfunction is made based on whether or not the CAN signal exceeds a predetermined threshold value. If the CAN signal exceeds a predetermined threshold value, it is determined that a malfunction has occurred, and the threshold is exceeded. Points that exceed the value are identified as malfunctioning locations.

JP 201421013 A

  However, in the conventional malfunction location identification method and system disclosed in Patent Document 1, it is possible to determine whether a malfunction has actually occurred in the circuit board and identify the malfunction location. The state of the circuit board before it occurs cannot be monitored. Further, in order to determine the presence or absence of malfunction, it is necessary to obtain the CAN signal by giving the output signal of the gyro sensor to the microcomputer. For this reason, in order to specify the malfunctioning portion, the output signal of the gyro sensor is required as a control signal for the microcomputer, and the presence of the gyro sensor and the microcomputer is required.

The present invention has been made to solve such problems,
A noise source that generates noise, a noise applying means that applies noise to a plurality of locations on the circuit board, a measuring device that measures noise transmitted to a predetermined location on the circuit board, and a noise level of noise measured by the measuring device A comparison device that compares the allowable level of noise allowed at a predetermined location, and an analysis device that identifies a vulnerable portion of noise resistance on the circuit board based on a plurality of comparison results obtained by the comparison device for a plurality of locations on the circuit board. Equipped with, and configured a noise resistant weak spot identification system on the circuit board.

  The present invention also includes a first step of applying noise generated by a noise source to a plurality of locations on the circuit board by a noise applying means, a second step of measuring noise transmitted to a predetermined location on the circuit board by a measuring device, The third step of comparing the noise level of the noise measured by the measuring device with the allowable noise level allowed at a predetermined location, and the noise resistance of the circuit substrate based on a plurality of comparison results obtained for a plurality of locations on the circuit substrate And a fourth step of specifying a vulnerable part, and configured a noise-resistant vulnerable part specifying method for a circuit board.

  According to the present invention, it is possible to monitor the state of a circuit board before a malfunction occurs, and it is possible to easily identify a weak point of noise resistance in a circuit board with a simple configuration. A weak spot identifying system and a noise resistant weak spot identifying method can be provided.

It is a figure which shows schematic structure of the noise tolerance weak location identification system in the circuit board by the 1st Embodiment of this invention. It is a flowchart showing the noise tolerance weak location identification method in the circuit board by the 1st Embodiment of this invention. It is a graph which shows the frequency spectrum of each signal measured in the predetermined location of a circuit board by the measuring apparatus which comprises the noise tolerance weak location specific system in the circuit board by 1st Embodiment. It is a figure which shows schematic structure of the noise tolerance weak location identification system in the circuit board by the modification of the 1st Embodiment of this invention. It is a figure which shows schematic structure of the noise tolerance weak location identification system in the circuit board by the 2nd Embodiment of this invention. It is a figure which shows schematic structure of the noise tolerance weak location identification system in the circuit board by the 3rd Embodiment of this invention.

  Next, the form for implementing the noise tolerance weak location identification system and noise tolerance weak location identification method in the circuit board by this invention is demonstrated.

  FIG. 1 is a diagram showing a schematic configuration of a noise resistant weak spot identifying system 1 in a circuit board according to the first embodiment of the present invention.

  The noise resistant weak spot identifying system 1 includes a function generator (hereinafter referred to as FG) 3 as a noise source that generates noise in order to identify a noise resistant weak spot in the circuit board 2. The FG 3 generates, as noise, a GSM signal of a communication system according to a predetermined digital communication standard used for a call of a digital mobile phone, in this embodiment, a GSM (Global System for Mobile Communication (registered trademark)) standard. The GSM signal generated by the FG 3 is given to the probe 4.

  The probe 4 gives the input GSM signal to the circuit board 2 by either radiation or conduction. The probe 4 mechanically scans the three-dimensional position with respect to the circuit board 2 by the probe scanning device 5, and applies noise to a plurality of predetermined positions on the entire surface of the circuit board 2. The probe scanning device 5 has sliders in the three axis directions of the x-axis direction, the y-axis direction, and the z-axis direction. The probe scanning device 5 moves the probe 4 in the three-axis direction according to a control signal from a personal computer (hereinafter referred to as PC) 6. To drive. The probe 4 and the probe scanning device 5 constitute noise applying means for applying a GSM signal as noise to a plurality of locations on the circuit board 2. For example, when a GSM signal is given from the probe 4 to the circuit board 2 by radiation, a space is provided between the tip of the probe 4 and the circuit board 2, and the GSM signal is given by conduction from the probe 4 to the circuit board 2. When being done, the tip of the probe 4 is brought into contact with the circuit board 2.

  A plurality of electronic components (not shown) are mounted on the circuit board 2 and connected by a wiring pattern (not shown). A speaker 8 is connected to the illustrated electronic component 7 via a pair of signal lines 9. The speaker 8 outputs sound according to the sound signal propagating through the pair of signal lines 9. A spectrum analyzer (hereinafter referred to as SPA) 11 is connected to the signal line 9 via an amplifier (hereinafter referred to as AMP) 10. The SPA 11 is applied to the circuit board 2 by the probe 4 and constitutes a measuring device that measures noise transmitted to a predetermined portion of the circuit board 2, that is, a signal line 9 that outputs an audio signal in the present embodiment. A PC 6 is connected to the SPA 11, and the SPA 11 outputs the measured noise to the PC 6.

  The PC 6 includes a central processing unit (CPU), a read only memory (ROM), and a random access memory (RAM). The RAM is used as a temporary storage work area in accordance with a computer program stored in the ROM, and predetermined processing is executed by the CPU. . In the present embodiment, the CPU, ROM, and RAM provided in the PC 6 constitute a comparison device and an analysis device. The comparison device compares the noise level of the noise measured by the SPA 11 with the allowable noise level allowed on the signal line 9 by the process executed by the CPU according to the computer program stored in the ROM. The analysis apparatus determines a vulnerable part of noise resistance in the circuit board 2 based on a plurality of comparison results obtained by the comparison apparatus for a plurality of places on the circuit board 2 by processing executed by the CPU according to the computer program stored in the ROM. Identify.

  Specifically, in the case where the comparison results obtained for all of a plurality of locations at which the noise level of noise measured by the SPA 11 is less than or equal to the allowable level are obtained by the comparison device, the analysis device determines that the noise level closest to the allowable level is the noise level. The location where the noise is measured is identified as the weakest vulnerable portion of noise resistance. Further, when a comparison result in which the noise level measured by the SPA 11 exceeds the permissible level is obtained at any of the plurality of locations in the comparison device, the analysis device measures the noise having a level that greatly exceeds the permissible level. The location is identified as the most vulnerable location with noise resistance.

  The comparison device and the analysis device are configured by software of a computer program in the PC 6 in the present embodiment, but are not limited to this. For example, an electronic circuit that performs the same function may be formed and configured by hardware.

  FIG. 2 is a flowchart showing a noise resistant weak spot identifying method for a circuit board according to the first embodiment of the present invention performed by a computer program in the PC 6.

  In this noise resistant weak spot identifying method, first, in a first step S1, a GSM signal generated in the FG 3 is applied as noise to a plurality of spots on the circuit board 2 by a noise applying means. At this time, the probe 6 is automatically scanned in three axial directions by the probe scanning device 5 under the control of the PC 6, and GSM signals are given from the probe 4 to a plurality of predetermined positions on the entire circuit board 2. The entire substrate 2 is an object to be evaluated for noise resistance. Next, in the second step S2, the noise transmitted to the signal line 9 of the circuit board 2 is measured by the SPA 11. Next, in the third step S3, the noise level of the noise measured by the SPA 11 is compared with the allowable noise level allowed in the signal line 9 by the comparison device. Next, in 4th step S4, the weak place of the noise tolerance in the circuit board 2 is specified based on the several comparison result obtained with a comparison apparatus about the several places of the circuit board 2. FIG.

  In the present embodiment, in the fourth step S4, when the comparison result in which the noise level of the noise measured by the SPA 11 is equal to or lower than the allowable level is obtained by the comparison apparatus for all of a plurality of locations, and the noise level is set to the allowable level. In the case where the comparison result exceeding one of the plurality of places is obtained in the comparison device, the analysis device identifies the vulnerable portion having the weakest noise resistance as described above.

  In the present embodiment, in the fourth step S4, in the case where the comparison results in which the noise level of the noise measured by the SPA 11 is equal to or lower than the allowable level are obtained in all of the plurality of locations by the comparison device, the analysis device sets the allowable level. The location where the noise level closest to is measured is identified as the weakest vulnerable location with noise resistance. In addition, when a comparison result in which the noise level measured by the SPA 11 exceeds the allowable level is obtained in any one of a plurality of locations in the comparison device, the noise having a level that greatly exceeds the allowable level is measured by the analysis device. The location is identified as the weakest vulnerable location with noise tolerance.

  According to the noise resistant weak spot specifying system 1 and the noise resistant weak spot specifying method in the circuit board 2 according to the present embodiment, a GSM signal is applied as noise to a plurality of locations on the circuit board 2, and the signal line of the circuit board 2 is The noise transmitted to 9 is measured by the SPA 11, and a comparison result between the measured noise level and the allowable noise level allowed in the signal line 9 is obtained at a plurality of locations on the circuit board 2. It can be grasped how much each GSM signal applied to the location affects the noise resistance of the signal line 9 of the circuit board 2.

  For this reason, it becomes possible to monitor the state of the circuit board 2 before a malfunction occurs, which could not be performed conventionally. Further, unlike the conventional malfunction location identification method and malfunction location identification system, it is not necessary to confirm the presence or absence of malfunction, and therefore it is not necessary to monitor the CAN signal obtained by giving the output signal of the gyro sensor to the microcomputer. For this reason, the presence of a gyro sensor or a microcomputer is no longer necessary, and it is possible to easily identify a weak point of noise resistance in the circuit board 2 with a simple configuration.

  Further, according to the noise resistant weak spot identifying system 1 and the noise resistant vulnerable spot identifying method in the circuit board according to the present embodiment, the weakest vulnerable spot in the circuit board 2 can be identified. In addition, it is possible to grasp whether or not the noise tolerance of the vulnerable part is within an allowable level. In addition, it is possible to quantitatively grasp how weak the noise tolerance of the vulnerable portion is based on the level difference between the measured noise level and the allowable level.

  In addition, according to the noise resistant weak spot identifying system 1 and the noise resistant vulnerable spot identifying method in the circuit board according to the present embodiment, the GSM signal used for the call of the digital cellular phone outputs the audio signal of the circuit board 2. 9 can be grasped as noise. In addition, by measuring the noise transmitted to the signal line 9 for outputting the audio signal of the circuit board 2 by the SPA 11, it is possible to grasp which frequency band the GSM signal used for the call of the digital cellular phone affects as noise. be able to.

  FIG. 3 shows a graph of the frequency spectrum of the signal on the signal line 9 measured by the SPA 11, and the horizontal axis of each graph shown in FIG. 3 (a) and FIG. 3 (b) is the signal frequency (HZ), The vertical axis represents an electric field (Field Strength) [dBμV] representing signal strength. The signal frequency on the horizontal axis is in the range of 20 [HZ] to 20 k [HZ] where speech is recognized.

  FIG. 5A is a graph showing the frequency spectrum of each signal on the signal line 9 with and without the GSM signal applied to a specific location on the circuit board 2 compared to the allowable noise level on the signal line 9. It is. In the graph, the frequency spectrum 21 of the black signal gives the GSM signal to the circuit board 2 and the frequency spectrum 22 of the gray signal gives the GSM signal to the circuit board 2 when the GSM signal is given to a specific part of the circuit board 2 (with the GSM signal). The frequency spectrum in the absence (no GSM signal), the gray line 23 is the allowable noise level (limit value) in the signal line 9.

  From the graph, when a GSM signal is given to a specific portion of the circuit board 2, the frequency spectrum 22 of the signal having a low signal intensity becomes the frequency spectrum 21 of the signal having a high signal intensity on the signal line 9. Understood. In addition, the intensity of the frequency spectrum 21 of the signal on the signal line 9 exceeds the limit value in a frequency range of about 4.5 k [HZ] or less, and abnormal noise (sound noise) is heard from the speaker 8. In this frequency range, the noise level causing the sound noise can be quantitatively grasped for each frequency from the magnitude of the intensity of the frequency spectrum 21 of the signal exceeding the limit value. Further, the noise tolerance margin in the signal line 9 can be grasped for each frequency from the level difference between the intensity and limit value of the frequency spectrum 21 of the signal in the frequency range exceeding about 4.5 k [HZ].

  FIG. 4B shows a case where a GSM signal is given to a specific part of the circuit board 2 without taking noise countermeasures on the circuit board 2 and a case where the circuit board 2 is given noise countermeasures and then applied to the specific part of the circuit board 2. It is a graph which compares the frequency spectrum of each signal of the signal line 9 in the case of giving a GSM signal with the allowable noise level in the signal line 9. The noise countermeasure was performed on the most vulnerable vulnerable location specified by the noise resistant vulnerable location specifying system 1 and the noise resistant vulnerable location specifying method on the circuit board according to the present embodiment. In the graph, the frequency spectrum 24 of the black signal is a frequency spectrum when the GSM signal is given to the circuit board 2 without taking noise countermeasures (there is a GSM signal), and the “GSM signal present” shown in FIG. It is the same as the frequency spectrum 21 of the signal “”. The frequency spectrum 25 of the gray signal is a frequency spectrum when a GSM signal is given to a specific part of the circuit board 2 after taking a noise countermeasure on the circuit board 2 (with a countermeasure), and the gray line 23 is the signal line 9. Is an allowable noise level (limit value).

  From the graph, a signal “with countermeasures” is obtained by performing noise countermeasures on the most vulnerable vulnerable part identified by the noise resistant vulnerable part identifying system 1 and the noise resistant vulnerable part identifying method on the circuit board according to the present embodiment. It is understood that the intensity of the frequency spectrum 25 of the signal on the signal line 9 is suppressed to a limit value or less in a frequency range of about 4.5 k [HZ] or less. For this reason, the noise countermeasure effect can be confirmed, and further, the countermeasure effect can be measured quantitatively.

  In addition, according to the noise resistant weak spot specifying system 1 and the noise resistant weak spot specifying method in the circuit board according to the present embodiment, the three-dimensional position of the probe 4 is mechanically scanned by the probe scanning device 5, and A GSM signal is applied from the probe 4 to a plurality of predetermined positions on the entire surface. For this reason, the trouble of manually scanning the probe 4 can be saved, and the identification work of the vulnerable part with noise resistance is facilitated.

  In the noise resistant weak spot identifying system 1 on the circuit board according to the first embodiment, the probe 4 is automatically scanned in the three axis directions by the probe scanning device 5 under the control of the PC 6, and the probe board 4 GSM signals were given to a plurality of predetermined locations throughout. However, the probe 4 can be moved within a limited range, and the GSM signal may be applied to a plurality of arbitrary locations in a limited area of the circuit board 2.

  The noise resistant weak spot identifying system 1A on the circuit board according to the modified example of the first embodiment is schematically shown in FIG. 4, and the noise applying means supplies the GSM signal, which is noise, to the circuit board 2. 4 and a probe position varying device 41. In the figure, the same or corresponding parts as in FIG. The probe position varying device 41 is composed of a slider that can move the probe 4 within a limited range in the x-axis direction, the y-axis direction, and the z-axis direction. The probe position changing device 41 arbitrarily changes the three-dimensional position of the probe 4 with respect to the circuit board 2 in accordance with an operation signal input from the keyboard of the PC 6, so that the probe position changing device 41 can be placed at any plurality of locations in a limited area of the circuit board 2. Apply GSM signal.

  The noise resistant weak spot identifying system 1A in the circuit board according to the modification of the first embodiment is the same as the noise resistant weak spot identifying system 1 in the circuit board according to the first embodiment except for the above points. Further, in the noise resistant weak spot identifying method using the noise resistant weak spot specifying system 1A on the circuit board according to the modification of the first embodiment, the keyboard of the PC 6 is operated in the first step S1 of the flowchart shown in FIG. Thus, only the point where the GSM signal is applied to a limited area of the circuit board 2 is different from the noise-resistant weak spot identifying method according to the first embodiment described above.

  According to the noise resistant weak spot specifying system 1A and the noise resistant weak spot specifying method in the circuit board according to the modification of the first embodiment, when the noise resistance evaluation target area in the circuit board 2 is limited, By arbitrarily changing the three-dimensional position of the probe 4 with respect to the circuit board 2 in a limited region of the circuit board 2 by the probe position changing device 41, the GSM signal from the probe 4 as noise at any plurality of locations on the circuit board 2 Can be applied. For this reason, the noise resistance weakness is obtained by arbitrarily selecting a signal line 42 on the circuit board 2, for example, a signal line 42 on the circuit board 2 and applying a GSM signal from the probe 4 to the signal line 42. The location can be identified with high accuracy.

  In the first embodiment, noise is applied to a plurality of predetermined locations on the circuit board 2, and in the above-described modification, noise is applied to any plurality of locations in a limited area of the circuit board 2. The noise may be comprehensively applied to at least the limited region of the circuit board 2 or the entire surface of the circuit board 2 by scanning the entire surface of the substrate 2 or the entire surface of the substrate.

  FIG. 5 is a diagram showing a schematic configuration of a noise resistant weak spot identifying system 1B on the circuit board according to the second embodiment of the present invention. In the figure, the same or corresponding parts as in FIG.

  In the noise resistant weak spot identifying system 1 in the circuit board according to the first embodiment, the noise applying means is composed of the probe 4 and the probe scanning device 5, but the noise resistant weak spot identifying system in the circuit board according to the second embodiment. In 1B, the noise applying means includes an array antenna 31 and an antenna selecting means. The PC 6 controls the probe scanning device 5 as in the first embodiment and does not control the position of the probe 4 but controls the opening and closing of the switch 32 constituting the antenna selection means.

  The array antenna 31 is configured such that a plurality of antennas 31a are arranged in the x direction and the y direction so as to face the back surface of the circuit board 2 in a region to be evaluated for noise resistance. In the present embodiment, the entire surface of the circuit board 2 is an object to be evaluated for noise resistance, but when only a part of the circuit area is to be evaluated for noise resistance, only the part of the circuit area is faced. The array antenna 31 is installed. Each of the plurality of antennas 31a is provided with a plurality of switches 32 like the array antenna 31 partially enlarged in FIG. The opening / closing of each switch 32 is controlled by the PC 6, and the antenna 31 a that radiates the GSM signal output from the FG 3 among the plurality of antennas 31 a configuring the array antenna 31 is turned on. Selected. By selecting this switch 32 by the PC 6, GSM signals are applied to a plurality of predetermined positions on the entire surface of the circuit board 2 one by one.

  Except for the above points, the noise resistant weak spot identifying system 1B in the circuit board according to the second embodiment is the same as the noise resistant weak spot identifying system 1 in the circuit board according to the first embodiment. Further, the noise resistant weak spot specifying method using the noise resistant weak spot specifying system 1B on the circuit board according to the second embodiment is the first step S1 of the flowchart shown in FIG. By being controlled, the antenna 31a that radiates the GSM signal is selected from the plurality of antennas 31a constituting the array antenna 31, and the GSM signal is applied to the circuit board 2 only as described above. This is different from the noise resistant weak spot identification method according to the embodiment.

  According to the noise resistant weak spot specifying system 1B and the noise resistant weak spot specifying method on the circuit board according to the second embodiment, the antenna 31a that radiates the GSM signal from among the plurality of antennas 31a configuring the array antenna 31. Is selected by the switch 32, GSM signals can be radiated from the array antenna 31 to a plurality of locations on the circuit board 2. For this reason, since the GSM signal can be applied to a plurality of locations on the circuit board 2, the time required to measure noise transmitted from the plurality of locations on the circuit board 2 to the signal line 9 on the circuit board 2 is shortened, and the location where noise resistance is vulnerable is identified. Work can be done quickly.

  FIG. 6 is a diagram showing a schematic configuration of a noise resistant weak spot identifying system 1C on a circuit board according to the third embodiment of the present invention. In the figure, the same or corresponding parts as in FIG.

  The noise resistant weak spot identifying system 1C on the circuit board according to the third embodiment is configured by a probe 4 whose noise applying means manually applies a GSM signal as noise to an arbitrary spot on the circuit board 2.

  The noise resistant weak spot identifying system 1C in the circuit board according to the third embodiment is the same as the noise resistant weak spot identifying system 1 in the circuit board according to the first embodiment except for the above points. Further, the noise resistant weak spot specifying method using the noise resistant weak spot specifying system 1C in the circuit board according to the third embodiment is a limited area of the circuit board 2 in the first step S1 of the flowchart shown in FIG. The only difference is that the GSM signal is manually applied from the probe 4 to the noise-resistant weak spot identifying method according to the first embodiment described above.

  According to the noise resistant weak spot specifying system 1C and the noise resistant weak spot specifying method in the circuit board according to the third embodiment, when the noise resistance evaluation target area in the circuit board 2 is limited, the probe 4 By manually moving the three-dimensional position with respect to the circuit board 2 manually, the GSM signal can be applied as noise from the probe 4 to any plurality of locations on the circuit board 2. For this reason, also in the third embodiment, as in the noise resistant weak spot identifying system 1A in the circuit board according to the modification of the first embodiment, the circuit board 2 is susceptible to noise, for example, the circuit board. By arbitrarily selecting the signal line 42 in 2 and applying the GSM signal from the probe 4 to the signal line 42, it is possible to specify the weak point of noise resistance with high accuracy.

  In each of the above embodiments and modifications, the case where the predetermined portion of the circuit board 2 that measures noise by the SPA 11 is the signal line 9 that outputs an audio signal has been described. However, the predetermined location of the circuit board 2 for measuring noise is not limited to this, and for example, a location where the voltage level fluctuation is small such as a power supply line for supplying power to the circuit board 2 or a control line for propagating control signals. But you can. In each of the above embodiments and modifications, the GSM standard has been described as an example of a predetermined digital communication standard used for a digital mobile phone call. However, the present invention is not necessarily limited to this communication method. Other communication methods may be used. Other communication methods include, for example, cellular methods (GSM (registered trademark), WCDMA (registered trademark), LTE, etc.) and short-range wireless communication (Wi-Fi (registered trademark), Bluetooth (registered trademark), etc.). Can be mentioned. Further, the noise is not limited to a signal conforming to a predetermined digital communication standard used for a digital mobile phone call. In each of the above embodiments and modifications, the case where the noise source is configured by FG3 has been described, but the mobile phone itself may be used as the noise source. In each of the above embodiments and modifications, the case where the measurement device that measures noise is the SPA 11 that measures a signal along the frequency axis has been described. However, an oscilloscope that measures the signal along the time axis is described. There may be.

1, 1A, 1B, 1C ... Noise resistant weak spot identification system 2 ... Circuit board 3 ... Function generator (FG: noise source)
4 ... probe 5 ... probe scanning device 6 ... personal computer (PC: comparison device / analysis device)
7 ... electronic component 8 ... speaker 9 ... signal line (predetermined location)
10 ... Amplifier (AMP)
11 ... Spectrum analyzer (SPA: measuring device)
31 ... Antenna array 31a ... Antenna 32 ... Switch (antenna selection means)
41 ... Probe position varying device

Claims (10)

  A noise source that generates noise, a noise applying unit that applies the noise to a plurality of locations on the circuit board, a measurement device that measures the noise transmitted to a predetermined location on the circuit board, and the measurement device that measures the noise A comparison device that compares the noise level of the noise with an allowable noise level that is allowed at the predetermined location, and the noise tolerance of the circuit substrate based on a plurality of comparison results obtained by the comparison device at a plurality of locations on the circuit substrate. A noise resistant weak spot identifying system on a circuit board comprising an analysis device for identifying a vulnerable spot.   When the comparison result in which the noise level is less than or equal to the allowable level is obtained for all of a plurality of locations, the analysis device may be configured such that a signal at a level closest to the allowable level is measured, and the noise level is the allowable level. When the comparison result exceeding the level is obtained for any one of a plurality of locations, the location where the signal with the level that greatly exceeds the allowable level is measured is identified as the weakest vulnerable location with noise resistance. The noise-resistant weak spot specific system of Claim 1.   The noise generated in the noise source is a signal according to a predetermined digital communication standard used for a call of a digital mobile phone, the predetermined portion of the circuit board is a signal line for outputting an audio signal, and the measuring device is The noise resistant weak spot identifying system according to claim 1 or 2, wherein the system is a spectrum analyzer.   The noise applying means mechanically scans a probe that gives the noise to the circuit board, and a three-dimensional position of the probe with respect to the circuit board, and applies the noise to a plurality of predetermined positions on the entire surface of the circuit board. The noise resistant weak spot identifying system according to any one of claims 1 to 3, wherein the system is configured with an applied probe scanning device.   The noise applying means includes an array antenna that emits the noise facing the circuit board in a region to be evaluated for noise resistance, and an antenna that emits the noise from among a plurality of antennas constituting the array antenna The noise-resistant weak spot identifying system according to any one of claims 1 to 3, characterized by comprising an antenna selection means for selecting   The noise applying means includes: a probe that applies the noise to the circuit board; and a three-dimensional position of the probe with respect to the circuit board that is arbitrarily changed, and the noise is applied to a plurality of locations in a limited region of the circuit board. 4. The noise-resistant weak spot identifying system according to claim 1, comprising a probe position varying device to be applied. 5.   4. The noise-resistant weak point identification according to claim 1, wherein the noise applying unit includes a probe that manually applies the noise to an arbitrary part of the circuit board. 5. system.   A first step of applying noise generated by a noise source to a plurality of locations on the circuit board by a noise applying means; a second step of measuring the noise transmitted to a predetermined location of the circuit board by a measuring device; and the measuring device. A third step of comparing a noise level of the measured noise with an allowable level of noise allowed at the predetermined location, and noise resistance in the circuit board based on a plurality of comparison results obtained at a plurality of locations on the circuit board A method for identifying a noise-resistant weak spot on a circuit board, comprising:   In the fourth step, when the comparison result in which the noise level is equal to or lower than the allowable level is obtained for all of a plurality of locations, the noise level at the level closest to the allowable level is measured, and the noise level is When the comparison result that exceeds the allowable level is obtained for any of a plurality of locations, the location where the noise at the level that greatly exceeds the allowable level is measured is identified as the weakest vulnerable portion of noise resistance. The method for identifying a noise-resistant weak point according to claim 8, characterized in that: In the first step, a signal according to a predetermined digital communication standard used for a call of a digital mobile phone is applied to the plurality of locations on the circuit board as the noise,
10. The noise resistant weak spot identifying method according to claim 8 or 9, wherein, in the second step, the noise transmitted to a signal line for outputting an audio signal of the circuit board is measured by a spectrum analyzer.

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