JPH0498163A - Probe drive device - Google Patents

Abstract

PURPOSE:To conduct contact with necessary positioning precision and contact pressure, by providing a parameter control portion, and regulating freely the parameters of its X axis and Y axis servo control portions. CONSTITUTION:A sequence control portion 1 sends out new inspection point position command signals to Z axis, Y axis, X axis servo control portions 2, 3, 4, and at the same time outputs a parameter timing signal P. By means of the signal P, Y axis and X axis parameter signals n, o which are in accordance with stop precision necessary for their inspection points, are outputted to control portions 3, 4 from a parameter control portion 10. As a result, control portions 3, 4 drive an XY table 9 with the optimum servo characteristic which is in accordance with inspection points. Also, the control portion 2, too, is contacted under contact pressure which is in accordance with each inspection point, by means of a Z axis parameter signal (m) which generates contact pressure optimum for its inspection points. As a result, sure contact is assured at all times, and a high precision inspection is conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a probe driving device, and particularly to a probe driving device used in a flying probe device used in continuity and insulation testing of printed wiring boards (hereinafter referred to as PWBs).

[Technological environment]

In recent years, as electronic devices have become more sophisticated, more compact, and more multifunctional, PWBs have become significantly more dense and accurate. Therefore, in order to guarantee the quality of PWBs, it has become a major issue to inspect the conductivity and insulation of fine circuits and through holes in PWBs and to reliably detect defects therein.

Generally, when testing a PWH, a universal testing method is used in which a large number of probe pins are brought into contact with the PWB to be tested at the same time, and continuity and insulation between the probe pins is measured. In this case, a large number of probe pins are arranged on a grid with regular pitches such as 2.54 mm, but the
Due to the increasing density and precision of WBOs, PWBs that cannot be tested using the universal method are emerging.

Therefore, a test jig is required in which probe pins are arranged so that the probe pins can contact the test points of each circuit pattern for each individual PWB.

However, as the types of PWBs continue to increase, the cost of inspection jigs in the universal system and the time required to prepare them are increasing, and a solution to this problem is desired.

[Common technology]

In order to cope with the above-mentioned situation, a wiring inspection inspection method called a flying probe method is attracting attention. In this method, a probe that can move in the X direction, Y direction, and Z axis direction is placed on the PWBO to be tested, and the probe is brought into contact with each circuit pattern of each PWB to test continuity and insulation for each circuit pattern. It is something.

It has excellent features such as there is no need to prepare a jig for each PWB, and it is also possible to blow into areas other than the grid. However, compared to the universal method, this method requires the probe to be moved for each inspection point, so it has an essential drawback in that it takes longer to inspect.

Therefore, in order to take advantage of the characteristics of the flying probe machine and compensate for its shortcomings, it is necessary to have stable, high-speed, and highly accurate positioning, as well as a probe drive that enables reliable contact of the probe at each inspection point.

[Conventional technology]

A conventional probing drive device includes a sequence control section that generates continuous spatial positions of the probe tip, and an X-axis control section that inputs an X-axis position command signal output from the probing sequence control section and outputs an X-axis control signal. The servo control section and the Z section that inputs the X-axis control signal and outputs the Z-axis drive signal.
The Z axis of the probe tip is controlled by the axis drive unit and the Z axis drive signal.
a probing head that determines the position in the direction and inputs a Z-axis feedback signal to the Z-axis servo control section; and an X-axis that inputs the X-axis position command signal output from the probing sequence control section and outputs a Y-axis control signal. a servo control section, an X-axis drive section that inputs the Y-axis control signal and outputs an X-axis drive signal, and inputs an X-axis position command signal output from the probing sequence control section and outputs an X-axis control signal. an X-axis servo control section, an X-axis drive section that inputs the X-axis control signal and outputs an X-axis drive signal, and an X-axis drive section that inputs the X-axis drive signal and the X-axis drive signal and controls the Y-axis and Y-axis of the probe.
It is configured to include an XY child table that performs positioning in the axial direction, outputs Y-axis feed and back signals, and X-axis feedback signals, and inputs them to the X-axis servo control section and the X-axis servo control section, respectively.

Next, a conventional probe driving device will be described in detail with reference to the drawings.

FIG. 2 is a block diagram showing a conventional example.

When the sequence control section 1 generates the coordinates of the inspection point, it inputs an X-axis position command signal to the X-axis servo control section 3. The X-axis servo control unit 3 outputs a signal between the Y-axis feedback signal k output from the XY child table (specifically, the position, velocity, and acceleration of the XY child table in the Y-axis direction) and the aforementioned X-axis position command signal. Servo calculation processing is performed according to predetermined servo parameters, and a Y-axis control signal e is output.

The X-axis drive unit 6 which receives the Y-axis control signal e amplifies the Y-axis control signal e, outputs an X-axis drive signal, and drives the Y-axis of the XY child table. When the XY table 9 is driven, it outputs a Y-axis feedback signal k corresponding to the drive.

Similarly, the sequence control section 1 includes the X-axis servo control section 4.
The X-axis position command signal C is also output to the The X-axis servo control unit 4 outputs an X-axis feedback signal from the XY child table (specifically, the position of the XY table in the X-axis direction,
Servo calculation processing is performed using predetermined servo parameters between the speed, acceleration) and the above-mentioned X-axis position command signal C, and an X-axis control signal f is output.

The X-axis drive unit 7 which receives the X-axis control signal C amplifies the X-axis control signal f, outputs the X-axis drive signal i, and drives the Y-axis of the XY child table. When the XY child table is driven, it outputs an X-axis feedback signal 1 corresponding to the drive.

On the other hand, regarding the Z-axis as well, the sequence control section 1 inputs a Z-axis position command signal a to the X-axis servo control section 2. The X-axis servo control unit 2 predetermines the Z-axis feedback signal j output from the probe head 8 (specifically, the position, velocity, and acceleration of the probe head 8) and the Z-axis position command signal a. Servo calculation processing is performed using the existing servo parameters, and a Z-axis control signal d is output.

The Z-axis drive section 5 which has input the Z-axis control signal d amplifies the Z-axis control signal d and outputs Zil! The probe head 8 is driven by outputting the lII driving signal g. When the probe head 8 is driven, it outputs a corresponding Z-axis feedback signal j.

In this way, the positioning of the probe head placed on the XY table with respect to the XY coordinates and the raising and lowering of the probe head, that is, contact control are performed.

However, as the PWB pattern becomes finer in recent years, it becomes necessary to position the probe head with higher precision, and the time required to stabilize the position tends to increase. In other words, since the Y-axis and Y-axis servo parameters are always operated using servo parameters that allow stopping with higher measurement accuracy, the same amount of time is required even for inspection points that require rough stopping accuracy.

In addition, in order to reliably blow into a heavily oxidized copper pattern, it is necessary to contact the oxide film with a force strong enough to break the oxide film. On the other hand, weak patterns require contact with weak force to minimize damage caused by contact.

However, in the conventional blowing drive device, contact can only be made with a constant contact pressure due to predetermined servo characteristics, which causes variations in contact resistance and cannot guarantee sufficient inspection accuracy.

[Problem to be solved by the invention]

In the conventional probe drive device mentioned above, the Y-axis and Y-axis servo control units operate with pre-adjusted servo parameters, so inspection points that require coarse positioning accuracy can be inspected with the same accuracy as inspection points that require high positioning accuracy. Since positioning is performed uniformly, positioning time is wasted and inspection time becomes longer. Additionally, since the Z-axis servo control unit operates with pre-adjusted servo parameters, it can only contact the pattern with a certain contact pressure, which can cause damage to weak patterns, and can cause oxide film to form on heavily oxidized patterns such as copper. It has the drawback that it cannot be inspected reliably due to phenomena such as failure to tear.

[Means to solve the problem]

The probe driving device of the present invention includes a sequence control section that generates continuous spatial positions of the tip of the probe, and an X-axis servo control section that inputs a Z-axis position command signal output from the sequence control section and outputs a Z-axis control signal. , a Z-axis drive section that inputs a Z-axis control signal and outputs a Z-axis drive signal;
The position of the probe tip in the Z direction is determined by the axis drive signal.
a probing head that inputs a Z-axis feedback signal to a servo control section of the axis; and an X-axis servo control section that inputs a Y-axis position command signal inputted from the probing sequence control section and outputs a Y-axis control signal. , a Y-axis drive section that inputs the Y-axis control signal and outputs a Y-axis drive signal, and an X-axis servo control that inputs the X-axis position command signal output from the probing sequence control section and outputs an X-axis control signal. 10 - An X-axis drive section that inputs the X-axis control signal and outputs the X-axis drive signal; and an X-axis drive section that inputs the X-axis drive signal and the X-axis drive signal and controls the Y-axis and Y-axis direction of the probe. Performs positioning, outputs a Y-axis feedback signal and an X-axis feedback signal, and inputs each to the X-axis servo control unit and the The apparatus includes a parameter control section which inputs a Z-axis parameter signal to the servo control section, a Y-axis parameter signal to the Y-axis control section, and an X-axis parameter signal to the X servo control section.

〔Example〕

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

FIG. 1 is a block diagram showing one embodiment of the present invention.

When the sequence control section 1 generates the coordinates of the inspection point, it inputs a Y-axis position command signal to the X-axis servo control section 3. The X-axis servo control unit 3 outputs a signal between the Y-axis feedback signal k output from the XY child table (specifically, the position, velocity, and acceleration of the XY child table in the Y-axis direction) and the aforementioned Y-axis position command signal. Servo calculation processing is performed according to the Y-axis parameter signal n output from the parameter control section 10, and a Y-axis control signal e is output.

The X-axis drive unit 6 which receives the Y-axis control signal e amplifies the Y-axis control signal e, outputs an X-axis drive signal, and drives the Y-axis of the XY child table. When the XY child table is driven, it outputs a corresponding Y-axis feedback signal k.

Similarly, the sequence control section 1 includes the X-axis servo control section 4.
Also input the X-axis position command signal C to In the X-axis servo control unit 4, the X-axis feedback signal 1 output from the XY child table (specifically, the position of the XY child table in the X-axis direction,
Servo calculation processing is performed using the X-axis parameter signal 0 output from the parameter control section 10 between the X-axis position command signal C (velocity, acceleration) and the above-mentioned X-axis position command signal C, and the X-axis control signal f is output.

The X-axis drive unit 7 which receives the X-axis control signal C amplifies the X-axis control signal f, outputs the X-axis drive signal i, and drives the Y-axis of the XY child table. When the XY child table is driven, it outputs an X-axis feedback signal 1 corresponding to the drive. on the other hand,
Regarding the Z-axis as well, the sequence control section 1 inputs a Z-axis position command signal a to the X-axis servo control section 2.

The two-axis servo control unit 2 sets parameters between the Z-axis feedback signal j (specifically, the position, velocity, and acceleration of the probe head 8) output from the probe head 8 and the aforementioned Z-axis position command signal a. Servo calculation processing is performed using the two-axis parameter signal m output from the control unit 10, and a Z-axis control signal d is output.

The Z-axis drive unit 5, which receives the Z-axis control signal d, amplifies the Z-axis control signal d, outputs the Z-axis drive signal g, and drives the probe head 8.

When the probe head 8 is driven, it outputs a corresponding Z-axis feedback signal j. In this way, the positioning of the probe head placed on the XY child table with respect to the XY coordinates and the raising and lowering of the probe head (in other words, contact control) are carried out, but the sequence control unit 1 sends a position command signal for a new inspection point. The parameter timing signal p is output at the same time as being sent to the X-axis servo control section 2, X-axis servo control section 3, and X-axis servo control section 4.

This parameter timing signal p is output according to the next inspection point, and is sent to the X-axis servo control unit 3 and the X-axis servo control unit 4 as a Y-axis parameter signal n corresponding to the stopping accuracy required at that inspection point. ,, instructs the parameter control unit 10 to output the X-axis parameter signal 0.
It is something.

Therefore, the X-axis servo control section 3 and the X-axis servo control section 4 can drive the XY child table with optimal servo characteristics according to the inspection point, and no time is wasted for stopping.

・Furthermore, the two-axis servo control unit 2 also uses the parameter timing signal p output from the sequence control unit 1 to send the Z-axis parameter signal m to the parameter control unit 10 to generate the optimum contact pressure for that inspection point. Enter from 10.

Therefore, depending on each inspection point, for example, in order to reliably blow into a heavily oxidized copper pattern, the contact pressure must be applied with enough force to break the oxide film, and with weak patterns, the contact pressure must be applied to minimize the damage caused by the contact. Therefore, it is possible to make contact with a weak force, and compared to the conventional case where contact can only be made with a constant contact pressure, contact can be made with stable contact resistance, and sufficient inspection accuracy can be guaranteed.

〔Effect of the invention〕

The probe drive device of the present invention is provided with a parameter control section, so that the servo parameters of the Y-axis and Y-axis servo control section can be freely adjusted. Since minute inspection points that require positioning accuracy can be positioned with high precision, positioning time is not wasted, and as a result, inspection time can be shortened. Also,
By providing a servo parameter control unit for the Z-axis servo control unit, the servo parameters of the Z-axis servo control unit can be adjusted freely, so low contact pressure is required for weak patterns, and strong contact is applied to patterns that are heavily oxidized, such as copper. It is possible to make contact with pressure, which has the effect of always guaranteeing reliable contact and enabling highly accurate inspection.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional example. ■...Sequence control unit, 2...X-axis servo control unit, 3...Y-axis servo control unit, 4...X-axis servo control unit, 5...Z-axis drive unit, 6...・Y-axis drive unit, 7...
・Two-axis drive unit, 8... Probing head, 9...
XY table, 10...Parameter control unit, a...Z-axis position command signal, b...X-axis position command signal, C...X-axis position command signal, d...X-axis control signal,
e...Y-axis control signal, f...X-axis control signal, g...
・Z-axis drive signal, h...Y-axis drive signal, i...Z-axis drive signal, j...Z-axis feedback signal, k...
Y-axis feedback signal, ■...X-axis feedback signal, m...Z-axis parameter signal, O...X-axis parameter signal, p...parameter timing signal.

Claims (1)

[Claims] a sequence control unit that generates continuous spatial positions of the probe tip; a Z-axis servo control unit that inputs a Z-axis position command signal output from the sequence control unit and outputs a Z-axis control signal; and a Z-axis servo control unit that outputs a Z-axis control signal. a Z-axis drive unit that inputs and outputs a Z-axis drive signal; a probing head that determines the position of the probe tip in the Z direction based on the Z-axis drive signal and inputs a Z-axis feedback signal to the Z-axis servo control unit; a Y-axis servo control section that inputs the Y-axis position command signal output from the probing sequence control section and outputs a Y-axis control signal; and a Y-axis drive section that inputs the Y-axis control signal and outputs a Y-axis drive signal. , an X-axis servo control unit that inputs the X-axis position command signal output from the probing sequence control unit and outputs an X-axis control signal; and an X-axis drive that inputs the X-axis control signal and outputs an X-axis drive signal. and a Y-axis servo control section which inputs the Y-axis drive signal and the X-axis drive signal to position the probe in the X-axis and Y-axis directions, and outputs a Y-axis feedback signal and an X-axis feedback signal, respectively. Inputs the XY table to the X-axis servo control unit and the timing signal output from the probing sequence control unit, and inputs the Z-axis parameter signal to the Z-axis servo control unit and the Y-axis parameter signal to the Y-axis control unit for X servo control. A probe driving device comprising: a parameter control section into which an X-axis parameter signal is input.