WO2006136139A1

WO2006136139A1 - Device for transmitting electrical signals between a tester and a test adapter

Info

Publication number: WO2006136139A1
Application number: PCT/DE2006/001040
Authority: WO
Inventors: Josef Schäfer
Original assignee: Jhs Technik
Priority date: 2005-06-22
Filing date: 2006-06-13
Publication date: 2006-12-28
Also published as: DE102005030551B3

Abstract

The invention relates to a device which allows to establish a detachable electrical connection between a tester (12) and a test adapter (11), such as, e.g., between a semiconductor tester and a probe card or other electrical test device and their test adapters. The inventive device (10) is provided with contact pins (15) that are mounted so as to be axially mobile. Said pressure-impinged contact pins (15) are connected to surface contacts (14) of the translator circuit board (13) of a test adapter (11) and can be connected to a tester (12) via a translator circuit board (17). The contact pins (15) are mounted so as to be axially mobile in guide bores (28, 29) of two plane-parallel boards. The contact pins (15) are in electrical contact in the metallized guide bores (12) of the translator circuit board (17), thereby establishing electrical contact to the translator circuit board (17). The contact pins (15) are also associated with spring elements (24) which are housed in separate spring bores (23) in a separate spring element board (22).

Description

Title: Device for transmitting electrical signals between a tester and a test adapter

Description:

The invention relates to a mechanical device with which a detachable electrical connection between a tester and a test adapter or plug can be made. See testers for semiconductors, printed circuit boards, wiring harnesses etc ..

Such devices are known and are usually constructed with spring-loaded contact pins. They serve, for example, to transmit one or more electrical signals from one module to another. These devices can also be used for signal transmission in plugs or other electrical interfaces.

Background of the invention:

For the purpose of electrical signal transmission between two modules or cables, devices, connectors or the like are constructed. So that the connection is solvable at any time and can be repeated frequently, spring contact pins are usually used for this purpose. These spring contact pins consist of a pressure spring-loaded contact piston, which together with the Compression spring is mounted axially movable in a housing. With its designed as a contact tip end of the contact piston comes into contact with the contact point on a printed circuit board or a different type of electrical contact. The same applies to its rear end, which is connected to a contact piston or with a solder, - crimp, - or wire wrap connection with an electrical contact point or with a wire. The two contact points are fixed to one another and pressed against each other via a mechanism or via screws, vacuum or pneumatics. If necessary, the electrical connection can be released at any time with little signs of wear at the contact points and connected again. Corresponding devices are known from DE 199 54 041 A1 and US 6650 134 B1.

These types of electrical connections come e.g. For testers to be connected via an electrical interface with a test adapter or with a probe card.

In the course of further development, more and more often faster signals and smaller currents have to be transmitted. For this purpose, conventional spring contact pins with high and fluctuating volume resistances with the interference of interference signals in high-frequency measurements are not always suitable. In addition, o.g. Solutions with spring contact pins very expensive.

Explanation of the invention:

The invention is based on the object to provide a device in which via a releasable electrical connection fast electrical signals can be transmitted safely and controlled and that the costs are reduced by a simple structure.

This object is solved by the subject matter of claim 1. The dependent claims indicate advantageous embodiments. The device is used, for example, in electrical testers. Here the measuring electronics of the tester is connected to the device and serves as a spring-loaded intermediate interface. A test adapter with a suitable electrical interface is placed on the spring-loaded intermediate interface and thereby electrically connected to the tester. The electrical contact to the test part is then made via different contacts. Test adapters for the testing of wafers (probescards), printed circuit boards or cables in this way can be associated with a tester.

In this case, in a device for transmitting electrical signals, the rigid contact pins are axially movably mounted in through bores of a plurality of plane-parallel plates, and the pressure springs associated with the contact pins are accommodated separately in bores of a housing connected to the plate. One of the plates is a converter - circuit board.

The electrical connection between the contact pin and a surface contact on a printed circuit board is made via printed conductors on a converter - printed circuit board (Translatorplatine). In the converter circuit board are holes that are metallized or equipped with an electrically conductive sleeve.

The contact pins are guided in the holes of the converter - PCB and thus provide the electrical contact to the circuit board and thus to

Intermediate interface ago, which in turn is connected to an electrical module or a cable.

Thus, the current no longer flows through the spring-loaded element in the spring contact pin and the number of contact points is thereby reduced. The electric

Resistance is reduced and the cost of expensive spring contact pins and for the

Wiring is saved.

The two electrical interfaces are pressed by vacuum, pneumatic or mechanical from both sides against the device and thus produce a mechanical and an electrical contact. One of the two modules can be an electrical tester, which is connected with its measuring electronics to an interface. The device according to the invention can be integrated in the tester as an interface. The device can also be set up on the tester interface to build custom test solutions.

The second assembly to which an electrical contact is made may be an electrical test adapter used to test a wafer, chip package, circuit board, or plug. The test adapters have an electrical interface and are placed with this on the device.

In a particularly advantageous embodiment, the through bores in the converter circuit board are equipped with electrically conductive contact sleeves, in which the rigid contact pins are mounted to slide in an axially movable manner. As a result, the life of the device can be increased and the electrical contact with the converter circuit board is improved.

A secure electrical contact between the contact pin and the metallized bore (or contact sleeve) in the converter - circuit board is achieved in that a ball is arranged between the compression spring and the contact pin. Thus, a transverse force is generated by the force of the spring and the system of the ball on the conical tip on the contact pin, which thus enables a secure contact with the converter - circuit board.

The connection of converter - PCB to electrical devices or assemblies can be made via cable, spring contact pins, connectors, etc.

The converter board is typically mounted in the board assembly where the housing is assembled with the springs and balls, but may be mounted elsewhere if desired.

The converter PCB can be freely designed and thus adapted to the interface geometries. In the case of high-frequency or critical signals, the printed conductors can have an additional grounding position in the Printed circuit board structure are protected. Individual printed conductors can also be improved in their signal quality by shielded guides on the printed circuit board.

In the case of plug constructions, the attachment of cables is simplified, as they can already be pressed into the converter circuit board in advance.

The arrangement of the contact pin coordinates can look different on the spring side than on the opposite side of the interface. That is, the contact pins can be installed at an angle and thus a larger number of contact points on a small area safely contact.

To ensure that the pens can be loaded easily, the exact drilling position is determined by software in each individual plate and the pens can thus easily be passed through the individual plates during assembly.

The device according to the invention has the advantage that due to the physical separation of the contact pin and the compression spring, smaller grid intervals are achieved on the spring side as well as on the interface side. The fact that the spring is housed in a bore, no coat is required as in the conventional spring pin and thus the distances of the spring elements are reduced. This in turn means a much higher density of spring elements and thus a greater number of pins. This allows higher test point densities to be contacted on the test adapter.

Another advantage is that, as a result of the separate placement of contact pin and compression spring, the design of the compression spring can be independent of the design of the contact pin. The life of the device can be significantly increased by more stable contact pins and optimally sized compression springs, since the springs are no longer limited in length and can have a larger diameter.

The compression springs and the balls can be quickly and easily mounted in the separate housing and fall out over a cover plate against be secured. This structure is considerably less expensive compared to conventional spring bed assemblies with spring contact pins.

Another advantage over conventional spring pin assemblies is that the accuracy of the contact pins through the guide in the upper and lower plates is much better.

For electrically demanding signal transmission, e.g. For high-frequency measurements, a non-electrically conductive ball can be inserted between the spring and the rigid pin. This prevents the current flowing through the spring and thus generates interference fields, which may be the case with conventional spring contact pins.

Furthermore, in the case of critical signal transmission in the higher frequency range, the contact pins can be shielded via an insulator and a metallic shield up to the contact point. The shield at the rear end has contact with the converter PCB. On the converter circuit board is attached a pedestal connected to ground. The mass, in turn, is associated with the tester or assembly. The screen is e.g. over a foam mat which is mounted in the upper area, pressed against this ground surface. The screen can also be fixed with the mass on the

Converter circuit board to be connected. In this case, a via can then be mounted on the converter circuit board into which the shield is soldered via a thin contact. The shield can also be pressed with a spring element against the converter circuit board or against the interface.

In the invention, much higher currents can be passed through the device with the contact pins than with spring contact pins at a comparable grid spacing. Furthermore, the pressing force of the contact pin is higher due to the larger spring element and thus it comes at higher currents not so fast to a burning at the contact tip. Since the contact pins can be made much more stable at smaller pitches As spring contact pins, here also a higher reliability can be granted in the labor input. The higher contact pressure also increases the contact reliability at the contact point.

A simple clamping of the rigid pins against falling out can be achieved in that between the guide plates, a foam mat is used, in which the inserted pins are clamped.

drawing

The invention will be explained in more detail with reference to the figures of the drawing with reference to several embodiments. Show it:

Fig.1. a first embodiment of the device 10 according to the invention as an interface for transmitting electrical signals in a schematic not to scale representation in section;

Fig.2. a top view of a tester interface 41 with a multiple arrangement of the device 10 of Figure 1 without the test adapter 11;

Figure 3. a further embodiment of a device of Figure 1 in a schematic not to scale representation in section;

Figure 4. a side view of the device of Figure 3; and

Figure 5. a plan view of a converter - circuit board 17 of the apparatus of Figure 1 with examples of traces course 47; Description of the embodiments

FIG. 1 schematically shows a device 10 as an interface for transmitting electrical signals between a tester 12 and a test adapter 11. The device 10 can also serve as an electrical interface between two modules that are not used for an electrical test.

The test adapter 11 is electrically and mechanically connected to a converter circuit board 13. On the converter - circuit board 13 surface contacts 14 are arranged on the bottom in a defined arrangement. The surface contact 14 is contacted via a contact pin 15, in which the test adapter 11 is pressed either mechanically, by vacuum or pneumatically on the rigid contact pins 15 and on the plate assembly 21. The test adapter 11 is centered on the plate assembly 21, not shown centering.

The contact pin 15 is guided in a guide plate 16 in a guide bore 29 and a converter - circuit board 17 in a metallized guide bore 28. Between the two plates spacer plates 18, 19, 20 are mounted. The holes in the spacer plates 18, 19, 20 are drilled in diameter larger than the guide holes 28, 29 in the guide plate 16 and the converter - circuit board 17. The plates 16, 18, 19, 20, 17 are mounted in parallel over each other and are about Not shown centering pins fixed to each other.

In the illustrated and described embodiment of the invention, the plates 16, 18, 19, 20, 17 are attached to each other. If necessary, fewer plates can be used and spacers are mounted between the individual plates.

A plate assembly 21 is placed on a spring element plate 22 and fixed to each other via centering pins, not shown. The contact pin 15 is mounted in alignment with a spring bore 23. The spring bore 23 is with a Spring element 24 and a ball 25 equipped. With a cover plate 26, the spring bores 23 are covered and thus the spring element 24 can no longer escape.

By placing the test adapter 11 and the pressing of the surface contacts 14 against the contact pins 15, in turn press the contact pins 15 on its rear end against the balls 25 and the spring elements 24th

The contact end 27 of the contact pin 15 is selected in shape to match the diameter of the ball 25 so that a slight transverse force acts on the contact pin 15 and thus secure electrical contact is made to the metallized guide bore 28 in the converter circuit board 17.

Via the converter circuit board 17, the electrical current is conducted from the metallized guide bore 28 via conductor tracks 5, 47 to a surface contact 30 or to a connector 31. The arrangement of the surface contacts 30 is selected according to the continuing interface.

If a detachable interface is desired on the tester side 12, surface contacts 30 are mounted on the converter circuit board 17. These are contacted via spring contact pins 32 by the contact piston 34 of the spring contact pin 32 presses against the surface contact 30. The spring contact pins 32 are connected via a wire 33 with the measuring electronics, not shown, in the tester 12.

When a firm connection is to be established between the tester interface 48 and the device 10, 17 connectors 31 are applied to the converter circuit board. It is then made via a connector 35 and cable the connection to the measuring electronics. In this case, vias are provided on the converter circuit board 17 instead of surface contacts 30. As a further embodiment, a contact sleeve 36 can be inserted in the guide bore 28 in the converter circuit board 17, so that the electrical contact with the contact pin 15 is improved. This also increases the service life of the device 10.

The contact pins 15 can also be installed obliquely in the plate assembly 21, so that even closely spaced surface contacts 14 can still be contacted on the printed circuit board 13 (not shown). On the spring side of the contact pin 15, the distances can then be selected so that the spring elements 24 can be dimensioned correspondingly large so that even the required spring force can be generated. This embodiment is not shown.

Between the guide plate 16 and the spacer plate 18, a foam mat 37 can be inserted. The contact pins 15 are inserted from above through the guide plate 16 and then through the spacer plate 18. The contact pins 15 pierce the foam mat 37 and are thus held in the same clamping.

In the spring element plate 22 spring bores 23 are mounted, which have a cone 38 at its upper end and are not completely drilled through to the diameter of the spring bore 23. The reduced bore diameter can also be achieved with a stepped drill bit. As a result, the balls 25 are secured in the spring bore 23 at the top of the cone 38 against falling out.

For this purpose, a thin end plate, not shown, with smaller holes between the spring element plate 22 and the converter - circuit board 17 can be attached. Through this plate falling out of the balls can also be secured. This end plate is then e.g. connected by screws with the spring element plate 22. This solution is not shown.

For high-frequency and sensitive electrical signals, the contact pins 15 are surrounded by an insulator 39 and a metallic shield 40. The screen 40 is on the converter - circuit board 17 on a ground surface 49, or is connected via a nose on the converter - circuit board 17 to ground. On the upper side, the foam mat 37 presses against the screen 40 and thus presses it against the converter circuit board 17. The contact pin 15 can move easily in the insulator 39 in the longitudinal direction.

The test adapter 11 can be used for the test of wafers (probe card), printed circuit boards, plugs or other electrical assemblies. Depending on the application, a corresponding structure is produced.

For the construction of a new test adapter 11, a new converter - circuit board 13 is required. The surface contacts 14 are connected via printed conductors with contacts, not shown, which in turn are brought into contact with the part to be tested (test object). The arrangement of the surface contacts 14 results from the construction of the device 10.

Due to the placement of the spring elements 24 in a separate space (spring bore 23) in the axial extension of the contact pin 15 a lot of space is saved in the lateral spacing of the contact pins 15, so that the pitch of the contact pins 15 with each other and thus reduces the density of the contact pins 15 are considerably increased can.

FIG. 2 exemplarily shows a top view of a tester interface 41 (the test adapter 11 is not shown here). Here several devices 10 are arranged in a tester interface 41. The shape and size of the device 10 and the arrangement of the contact pins 15 is arbitrary. It can e.g. also arcuate segments are joined together to form a round tester interface 41.

The arrangement of the tester interface 41 may consist of individual segments of the device 10. However, it is also possible to construct a tester interface 41 in such a way that all the segments of the device 10 shown here consist of several large plates which are similar to the structure of the device 10 from FIG. FIG. 3 shows a further embodiment of the device 10 as a detachable plug 42. The plug 42 is fastened by screws in a screw hole 43 on a device, not shown. A converter circuit board 44 is positioned and contacted to match the contact pins 15, with the converter circuit board 44 typically attached to a housing. It may be a test adapter, tester interface or other electrical assembly.

FIG. 4 shows a side view of device 42. About a press-in contact 46 with pre-assembled wire 45 in the converter - circuit board 17, an electrical contact to a measuring device or an electrical assembly is made. In this embodiment eliminates the costly soldering of the wire 45 to a spring contact pin as is common in conventional plugs with detachable contacts.

FIG. 5 shows a plan view of the converter circuit board 17, on which the metallized guide bores 28 are connected to the surface contacts 30 via conductor tracks 47. Via the surface contacts 30, the connection to the tester interface 48 is established.

Furthermore, the guide holes 28 are enclosed with ground surfaces 49. On this ground surface 49 of the screen 40 is placed, which protects the contact pin 15 against electrical interference.

Bezugszeϊchenliste

Claims

claims

1. Device (10) for transmitting electrical signals between a tester (12) and a test adapter (11), with a plurality of plates mounted one above the other (16, 18, 19, 20, 17), the bores or guide bores (28, 29) in which contact pins (15) are movably guided in their longitudinal direction, wherein one of the plates (16, 18, 19, 20, 17) is a converter circuit board (17), whose guide bores (28) have electrically conductive walls, the one establish electrical connection to the contact pins (15) and the electrically conductive walls via printed conductors (47) with surface contacts (30) on the converter circuit board (17) are connected, so that the contact pins (15) with the test adapter (11) and the Surface contacts (30) with the tester (12) are connectable.

2. Device according to claim 1, wherein the contact with the tester (12) surface contacts (30) are arranged in a grid.

3. Apparatus according to claim 1 or 2, wherein on the converter - printed circuit board (17) in place of surface contacts

(30) vias are attached and via a connector

(31) a connection with the tester (12) can be produced on the unpacker circuit board (17).

4. Device according to one of the preceding claims, wherein the device (10) has a spring element plate (22) with spring elements (24), wherein the spring elements (24) act on the contact pins (15) resiliently.

5. Apparatus according to claim 4, wherein in the spring element plate (22) spring bores (23) are mounted, which are equipped with spring elements (24) and on one of the converter circuit board (17) facing side with balls (25).

6. The apparatus of claim 1, wherein the guide bore (28) of the converter circuit board (17) with electrically conductive contact sleeves (36) are fitted, in which the contact pins (15) are guided in their longitudinal direction movable.

7. The device of claim 1, wherein the converter circuit board (17) has a ground surface (49) on which a metallic shield (40) of a shielded contact pin (15) rests or connected via a nose with the converter circuit board (17) is and is thus electrically connected to ground.