JPH1038980A - Apparatus and method for probing circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform probing without a defect in electrical connection even if a flexible circuit board (FPC) deforms. SOLUTION: A lead position and height position data are obtained from an output signal of a capacitive displacement sensor 8 with waveforms having periodicity wherein the lead 11 shows a summit and a base shows a bottom of a valley with the capacitive sensor 8 across the lead of an FPC 1. Base on the obtained position data, the lead 11 to be probed is positioned immediately below a probe 4, while based on height data of the lead 11, a support 6 is brought close to a rear face of the FPC 1. Finally the probe 4 is brought into contact with the lead 11, wherein an amount of pushing the probe 4 is controlled based on the height data of the probe 11 so that pushing of the probe 4 is at a predetermined value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board probing apparatus and method, and more particularly to a flexible circuit board probing apparatus applicable to the analysis of a defective flexible circuit board.

[0002]

2. Description of the Related Art The prior art is disclosed in, for example,
There is a circuit board probing apparatus described in JP-A-8-052576.

FIG. 4 is a configuration diagram showing a conventional circuit board probing apparatus. The circuit board probing apparatus shown in FIG. 4 includes a base 2 on which a flexible circuit board (hereinafter, referred to as FPC) 1 to be probed is mounted, and a moving stage 3 under the base 2 for moving the base 2 together with the FPC 1 in a horizontal plane. A probe 4 disposed above the base 2 and electrically connected to the lead 11 provided on the upper surface of the FPC 1, a probe stage 5 for moving the probe 4 up and down, and a moving direction of the moving stage 3 above the base 2 A camera 19 that is arranged at a predetermined distance from the probe 4 so as not to overlap with the probe 4 and captures the lead 11 and outputs an image signal d. The camera 19 is connected to the camera 19 and receives the image signal d. Image processing unit 20 for detecting a position in a horizontal plane and outputting lead position data e
And a control unit 10 connected to the moving stage 3, the probe stage 5, and the image processing unit 20 and controlling the moving stage 3 to position the lead 11 directly below the probe 4 based on the lead position data e. Have. FPC1
Is a rectangle, and many leads 11 are arranged in a row along one side (or a plurality of sides) of the FPC 1. A lead 1 for connecting to a terminal of an integrated circuit device or the like mounted on the FPC 1 is provided.
Reference numerals 1 are also arranged in line corresponding to these terminals.

Next, the operation will be described. First, the movable stage 3 positions the leads 11 arranged in a predetermined row below the camera 19, and performs imaging. Next, the image signal d is processed by the image processing unit 20, and the position of the lead 11 is detected. More specifically, the image signal d is binarized to extract only the region of the lead 11, and the extracted region on a predetermined line (a straight line passing on each lead 11 in the direction of the column in which the leads 11 are arranged) on the image From the center coordinates of the moving stage 3 and the position coordinates of the moving stage 3
The position of each lead 11 is calculated. Next, based on the read position data e obtained by the above operation, the moving stage 3
Is performed, and the lead 11 is positioned just below the probe 4. Finally, the probing is completed by pushing the probe 4 toward the FPC 1 by a predetermined amount on the probe stage 5.

[0005]

When a failure occurs in an FPC affixed to a device substrate in a liquid crystal display device or the like, the FPC may be peeled off from the device substrate and analyzed. In this manner, the FPC is peeled off from the device substrate. In this case, wavy deformation occurs in the FPC.

In the above-described conventional circuit board probing apparatus, if the FPC has a wavy deformation as in the case where the FPC is peeled off for analysis, the camera 19 cannot be focused and the image cannot be taken. The probe load increases in a portion where the deformation is large, so that the FPC and the probe are damaged. Further, when the probe is pressed, the FPC is deformed and a contact failure occurs due to a displacement between the probe and the lead.

[0007]

According to the present invention, there is provided a circuit board probing apparatus on which a circuit board is placed, and a base which is open below a probing area of the circuit board and a lead of the circuit board are provided. A probe arranged on the surface side for making electrical connection with the circuit board leads, a probe stage for raising and lowering the probe, and a surface side opposite to the surface on which the circuit board leads are provided, A support disposed at a position facing the probe, a support stage for raising and lowering the support, a transfer stage for moving the base relative to the probe and the support in a horizontal plane, and a lead of the circuit board Lead position detecting means for detecting the position and height of the circuit board, and the circuit board according to the position and height of the leads on the circuit board detected by the lead position detecting means. Controlling the moving stage so as to position the lead directly below the probe, controlling the support stage so that the tip of the support is close to the circuit board, and controlling the probe so that the load of the probe is appropriate. And a control unit for controlling the stage, wherein the lead position detecting means is provided with a capacitive displacement sensor provided so as to face the surface of the circuit board on which the leads are provided, or By a combination of a light source that irradiates a light beam on a surface provided with a lead and a light position detecting element that is on an optical axis inclined with respect to the light beam and receives reflected light of the light beam from the circuit board. A triangulation distance measuring sensor can be used, and an FPC may be used as a circuit board.

According to the circuit board probing method of the present invention, a circuit board is placed on a base, the position and height of a lead on the circuit board are measured, and the lead on the circuit board is opposite to the lead according to the position and height. Place the support close to the side part,
A probe positioned directly above the lead according to the position and the height is pressed against the lead so as to have an appropriate contact load.

[0009]

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

The circuit board probing apparatus shown in FIG.
FPC 1 has an opening 21 in the probing area
Base 2 on which FPC 1 is mounted and a part of FPC 1 is bonded and fixed
A moving stage 3 below the base 2 for moving the base 2 together with the FPC 1 in a horizontal plane, and a probe 4 disposed above the base 2 and electrically connecting to a lead 11 provided on the upper surface of the FPC 1 A probe stage 5 for raising and lowering the probe 4, a support 6 disposed below the base 2 at a position facing the probe 4, a support stage 7 for raising and lowering the support 6, and an upper side of the base 2. The capacitance type displacement sensor 8 serving as a lead position detecting means for detecting the position and height of the lead 11 of the FPC 1 and being arranged at a predetermined distance so as not to overlap with the probe 4 in the moving direction of the moving stage 3. Amplifier 9 for amplifying output a of capacitance displacement sensor 8 and outputting read detection signal b
The moving stage 3 is connected to the probe stage 5, the supporting stage 7 and the amplifier 9, and controls the moving stage 3 to position the lead 11 directly below the probe 4, based on the lead detection signal b, The moving amount of the probe stage 5 is controlled so that
And a control unit 10 that controls the amount of movement of the stage 7 so that the height position of the stage 7 approaches the back surface of the FPC 1.
The capacitance type displacement sensor 8 is a sensor that generates a larger output as the metal surface approaches the tip.

Next, the operation will be described. FIG.
Capacitive displacement sensor 8 for lead 11 on PC 1
FIG. 2B is a schematic diagram showing the relationship between the position shown in FIG. 2A and the detection signal b.

The case where the leads 11 are arranged in line along the edge of the FPC 1 as shown in FIG. 2A will be described. After positioning the mold displacement sensor 8, the base 2 is moved so that the capacitance displacement sensor 8 crosses the lead 11 from the side of the FPC 1 to the opposite side. At this time, the lead 11 on the FPC 1
2 is an insulator, the lead detection signal b obtained from the amplifier 9 is the same as that shown in FIG.
As shown in (b), the capacitance type displacement sensor 8 is connected to the lead 1.
The waveform has a periodicity such that the peak is at the top of the mountain when it is on 1 and the bottom of the valley when it is on the substrate 12. Therefore, the position corresponding to the peak of the peak of this waveform is the position of the lead 11. Also, FPC1 has a wave-like deformation,
The output value at the top of each peak of the waveform changes according to the distance between the lead 11 and the capacitance sensor 8. Therefore, the height of the lead 11 at the corresponding position can be obtained from the output value at the peak of this mountain. That is, data of the position and height of each lead 11 is obtained from the detection signal b.

Next, the control unit 10 controls the movement of the moving stage 3, the probe stage 5, and the support stage 7, and performs probing on a predetermined lead 11.
That is, the lead 11 to be probed by the moving stage 3 is positioned directly below the probe 4 based on the position data of the lead 11 obtained by the above operation. Next, based on the height data of the lead 11 obtained by the above operation, the tip of the support 6 is brought close to the back surface of the FPC 1 by the support stage 7. Finally, the probe 4
Is brought into contact with the lead 11. At this time, the moving amount of the probe 4 is controlled based on the height data of the lead 11 so that the pushing of the probe 4 becomes a predetermined amount, that is, the probing load becomes a constant amount. I do.

The capacitance type displacement sensor 8 has a measurement area in a direction perpendicular to the displacement detection direction which is equal to or less than の of the pitch of the leads 11.

Even when the leads 11 are not arranged side by side along the edges of the FPC 1, the position and height of the leads 11 can be obtained by moving the base 2 so that the capacitive displacement sensor 8 crosses over the leads 11. Can be requested. The method of moving the base 2 so that the capacitance type displacement sensor 8 crosses over the lead 11 may be such that the operator looks at the FPC 1 and commands the control unit 10, or the FPC 1 can be accurately placed on the base 2. And the control unit 10 may automatically drive the moving stage 3 based on the design data of the position of the lead 11 on the FPC 1.

The present invention is also possible when the base 2 is fixed and the capacitance type displacement sensor 8, the probe stage 5, and the support stage 7 are moved in the horizontal direction.

FIG. 3 is a block diagram showing a second embodiment of the present invention.

The flexible circuit board probing apparatus shown in FIG. 3 has the same configuration and operation as the flexible circuit board probing apparatus shown in FIG. 1 except that the configuration and operation of the lead detecting means are different. So, below:
Only the configuration of the lead detecting means of the flexible circuit board probing apparatus of FIG. 3 and the operation of detecting the position and height of the lead 11 will be described.

The lead detecting means used in the flexible circuit board probing apparatus shown in FIG.
A laser diode (hereinafter referred to as L
D) 14, a projection lens 15 on the irradiation optical axis of the laser beam 13 for condensing the laser beam 13 on the FPC 1 to about the width of the lead 11, and a position from the optical axis of the laser beam 13. An optical position detecting element (hereinafter referred to as PSD) 16 which detects a displacement of a spot image of the laser beam 13 formed on the FPC 1 on the optical axis inclined by a fixed amount, a light receiving lens 17 which is an image forming lens thereof, and an output of the PSD 16 and a PSD amplifier 18 that receives c and outputs a read detection signal b.

The laser light 13 emitted from the LD 14 toward the FPC 1 is condensed on the FPC 1 by the light projecting lens 15, and the reflected light is imaged on the light receiving surface of the PSD 16 by the student lens 17. When the base 2 is moved so that the laser light 13 crosses the lead 11 on the FPC 1, the position of the lead 11 on the line where the laser light 13 crosses the lead 11 is scattered and reflected by the lead 11 and the base material 12. Since the rates are different, it can be detected from the amount of laser light 13 incident on the PSD 16. Further, since the PSD 16 can detect the position of the incident light point on the light receiving surface, the height of the FPC 1 can be calculated from the image forming position of the laser beam 13 on the PSD 16 by the principle of triangulation.

It should be noted that the probe 4 may be disposed below the base 2 and the support 6 may be disposed above, so that the FPC 1 is mounted on the base 2 such that the surface on which the leads 11 are provided faces downward. Good. When the leads 11 are provided on both sides of the FPC 1, the probe 4 may be arranged above and below the base 2, and the support 6 may be arranged above and below the base 2. Good.

The present invention can be applied not only to a flexible circuit board but also to a printed board made of glass epoxy, and the present invention is particularly effective when such a printed board has a large warpage.

[0024]

According to the circuit board probing apparatus and method of the present invention, the positioning of the lead and the amount of pushing of the probe are controlled based on the data of the position and height of the lead detected by the lead position detecting means. Therefore, even if the FPC is deformed, the probe load can be kept constant, so that the FPC does not damage the probe, and there is no displacement of the probe, so that the electrical connection can be reliably performed. This has the effect.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a relationship between a position of a capacitance displacement sensor 8 crossing over a lead 11 on the FPC 1 shown in FIG. 1 and a lead detection signal b.

FIG. 3 is a configuration diagram showing a second embodiment of the present invention.

FIG. 4 is a configuration diagram showing a conventional circuit board probing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 FPC 2 Base 3 Moving stage 4 Probe 5 Probe stage 6 Support 7 Support stage 8 Capacitive displacement sensor 9 Amplifier 10 Control part 11 Lead 13 Laser beam 14 LD 15 Light projection lens 16 PSD 17 Light receiving lens 18 PSD amplifier 19 Camera 20 Image processing unit a Capacitance sensor output b Lead detection signal c PSD output d Image signal e Lead position data

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H05K 3/00 H05K 3/00 T

Claims (5)

[Claims] A circuit board is mounted, and a base which is open below a probing area of the circuit board is disposed on a surface of the circuit board on which a lead is provided, and is electrically connected to a lead of the circuit board. A probe for making a proper connection, a probe stage for raising and lowering the probe, and a support disposed at a position opposite to the surface of the circuit board opposite to the surface on which the leads are provided, and A support stage for raising and lowering the support, a moving stage for relatively moving the base in a horizontal plane with respect to the probe and the support, and a lead position detecting means for detecting a position and a height of a lead of the circuit board, According to the position and height of the lead of the circuit board detected by the lead position detecting means, the lead of the circuit board is positioned just below the probe. A controller that controls a moving stage, controls the supporting stage so that the tip of the supporting member is close to the circuit board, and controls the probe stage so that the load of the probe is appropriate. Circuit board probing device. 2. The circuit board probing according to claim 1, wherein the lead position detecting means comprises a capacitance type displacement sensor provided so as to face a surface of the circuit board on which the leads are provided. apparatus. 3. A circuit according to claim 1, wherein said lead position detecting means comprises: a light source for irradiating a light beam on a surface of the circuit board on which the lead is provided; and a light source on the optical axis inclined with respect to the light beam. 2. The circuit board probing apparatus according to claim 1, further comprising a triangulation distance measuring sensor in combination with a light position detecting element for receiving the reflected light. 4. The circuit board probing apparatus according to claim 1, wherein the circuit board is a flexible circuit board. 5. A circuit board is mounted on a base, and a position and a height of a lead on the circuit board are measured, and a support is brought close to a portion of the circuit board opposite to the lead according to the position and the height. And probing the probe positioned directly above the lead according to the position and height so that the probe has an appropriate contact load.