JPH09180846A - Socket for integrated circuit test - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excellently hold contact between a columnar soldered integrated circuit and a socket by installing a support plate on a platform of the socket for a test. SOLUTION: This socket has a base part and a platform 14 to support an integrated circuit device 50 on it. Since columnar soldered 52 of the integrated circuit device 50 has a fair length, in order to support it over the total length, a support plate 54 is arranged on the platform 14. The support plate 54 has a wall 60 having a prescribed thickness to properly arrange the integrated circuit device 50 on the support plate 54 and the platform 14 so that a proper contact pin contacts with the desired columnar solder 52.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to apparatus for testing integrated circuits, and more particularly to an improved test socket in which an integrated circuit having a columnar solder lead and a contact pin of the test socket. It is possible to make reliable contact many times between.

[0002]

BACKGROUND OF THE INVENTION Critical integrated circuits are tested at elevated temperatures before they are installed in a product because many integrated circuits fail in a very short test period when they fail. These integrated circuits are often encapsulated in rectangular ceramic or plastic packages having contact pads or conductors, which contact pads or conductors are electrically connected to the integrated circuit. Testing integrated circuits requires temporary electrical contact to contact pads or conductors in the package of the integrated circuit. Test sockets are provided for this purpose, which are soldered to a printed circuit board having circuits suitable for testing special integrated circuits.

[0003]

The earliest forms have been lids hinged to the test socket along one edge, or clipped to the base of the test socket along several edges. A lid for gripping the integrated circuit when the lid is closed and forcing the contact pin of the test socket downward. It has been found that a hinged or clipped lid causes an abnormally directed mechanical component of force to occur during closure. The normal direction is defined by the vector perpendicular to the plane of the test socket. Forces acting in a direction other than the normal direction may cause movement of the integrated circuit with respect to the contact pins of the test socket, damage to the integrated circuit contact pads or conductors, cracks in the ceramic or plastic encapsulating the integrated circuit, or Breakage occurs.

The conventional test socket of US Pat. No. 5,247,250, assigned to the assignee of the present invention and also incorporated herein, forms a generally flat lower surface and an interior opening above the lower surface. By providing a test socket having a base having an upright wall extending from the lower surface for supporting the integrated circuit, an abnormal force created by the cover of the test socket during closing is offset,
The platform has a dangling leg extending from the platform toward the underside of the base, the leg terminating as an end projecting substantially perpendicular to the extension of the leg, the wall of the base being the platform. Further has a recess corresponding to the end of the leg of the leg that engages the end of the leg to prevent the platform from moving away from the underside of the base, but any portion of the platform Is allowed to move toward the lower surface of the base independently of the movement of the portion of the base, the test socket is disposed between the lower surface of the base and the platform and is in electrical contact with an integrated circuit on the platform and the platform. A contact having elasticity to support the platform in a space relationship with the lower surface while allowing elastic movement toward the lower surface of the integrated circuit. The integrated circuit is brought into contact with the elastic contactor by having a cover that holds the contact state with the platform and the elastic contactor and a latching member that releasably holds the cover with respect to the base. Retained.

Although the test socket of US Pat. No. 5,247,250 works well with integrated circuits having spherical solder as a conductor, it does not provide lateral support for long columnar solder. Also, it does not work well with devices having columnar solder type conductors, as the conductors undergo bending and breaking during testing.

[0006]

SUMMARY OF THE INVENTION The present invention provides a support plate that mounts to a conventional socket platform for accommodating long leads of post-solder type integrated circuits in US Pat. No. 5,247,250. Overcomes the limitations of the No. 1 test socket. The support plate is
It has one or more walls surrounding the area in which the device is to be placed so as to positively position the device with respect to the support plate.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same parts are designated by the same reference numerals.

FIG. 1 shows a test socket in accordance with the technique disclosed in US Pat. No. 5,247,250, generally designated by the reference numeral 10, the test socket 10.
Is a base 12 and a platform 1 supporting an integrated circuit.
4, a cover 16 that holds the integrated circuit in contact with the platform 14, and a latch 18, or latch, that attaches the cover 16 to the base 12 and maintains the integrated circuit in contact with the platform 14. The cover 16 is attached to the base portion 12 at a hinge, that is, a hinge portion 44 arranged at one end of the cover 16. Base 1
2 has a generally flat lower surface 20 from which four walls 22 extend upwards to form an open interior space.

The platform 14 has a generally square shape and is a nest for integrated circuits (not shown in FIG. 1).
t), i.e. having two raised alignment ridges forming a housing. Four legs 26 extend from the flat portion of platform 14 and terminate in outwardly projecting ends 28 which engage recesses 30 in wall 22 of base 12. The protrusion or protruding end 28 extends generally perpendicular to the leg 26. The end 28 may be projected inward instead of outward. End 28 of leg 26 of platform 14
The engagement of the recessed portion 30 of the base portion 12 with the recessed portion 30 of the base portion 12 prevents the platform 14 from moving away from the lower surface 20 of the base portion 12.
Since it extends most of the distance towards the underside 20 of the
Some or all of legs 26 and platform 14 may be moved toward lower surface 20 of base 12. Therefore, the platform 14 is free to "float" with respect to the base 12.
In position, that is, any part of the platform 14 is pushed down against the base 12 independently of the other parts of the platform 14. Therefore, the platform 14
Are freely tilted in any direction in response to forces applied unevenly to the integrated circuit. The movement of this platform 14 is more fully described in US Pat. No. 5,247,250.

The platform 14 is supported above the lower surface 20 of the base 12 by contacts, or contact pins 32.
The contact pin 32 is made of a resilient and electrically conductive metal such as copper and comprises a bent central portion 34 for providing the contact pin 32 with a spring type action. The contact pins 32 extend through slots or holes 36 in the platform 14 and contact the spherical solder formed in the integrated circuit. The ends of the contact pins 32 on the opposite side of the integrated circuit extend through the lower surface 20 of the base 12 for electrical connection to holes in the circuit board (not shown) to which the test socket 10 is attached. It is formed as a blade 42. The contact pins 32 are retained relative to the platform 14 and the base 12 by enlarged shoulders formed in the base 12 and shoulders that fit within opposing holes formed in the platform 14.

Referring now to FIG. When the integrated circuit device 50 has the columnar solder 52 instead of the spherical solder, the columnar solder 52 has a length, so that the integrated circuit device 50 has a length.
The body of the device is prevented from contacting the platform 14, and the platform 14 cannot house the integrated circuit device 50. Therefore, when pressure is applied to the integrated circuit device 50, the columnar solder 52 is bent or broken.
A support plate 54 is suitable to fit over the platform 14 to support the columnar solder 52 over its entire length.

The support plate 54 is attached to the platform 14 by two screws 56 or an adhesive, or simply rests on the platform 14. The support plate 54 has holes 58 that match the holes 36 in the platform 14 to support the columnar solder 52 over its length to prevent it from breaking while the columnar solder 52 supports the contact pins 32 of the test socket 10. It is thick enough to make electrical contact with. The relationship between the length of the columnar solder 52 and the desired thickness of the support plate 54 is clearly shown in FIG.

The support plate 54 includes suitable contact pins 32.
The support plate 54 and the platform 14 so that they contact the desired columnar solder leads or solder leads 52.
A wall 60 for positively arranging the integrated circuit device 50 with respect to and is provided. The wall 60 is continuous around the outer edge of the integrated circuit device 50, but may be shorter than shown.

Although the invention has been described with respect to only one embodiment, it will be apparent to those skilled in the art that many modifications are possible. For example, the support plate 54 may be attached to the platform 14
The attachment means may be any means, provided that all of the columnar solder 52 of the integrated circuit device 50 is accommodated and the desired length of the columnar solder leads 52 is available to electrically connect the contact pins 32. However, any size or thickness may be used. Further, the support plate 54 can be used with a wide variety of test sockets that need to be suitable for accommodating integrated circuit devices having columnar solder.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing components of a conventional test socket according to US Pat. No. 5,247,250.

FIG. 2 is an exploded perspective view showing a platform portion of a conventional test socket, a support plate of the present invention, and an integrated circuit device.

FIG. 3 is a cross-sectional view of an upper portion of a platform portion of a conventional test socket, a support plate of the present invention, and an integrated circuit device.

[Explanation of Codes] 10 ... Socket for Test 12 ... Base 14 ... Platform 16 ... Cover 18 ... Latch Member 50 ... Integrated Circuit Device 52 ... Columnar Solder 54 ... Support Plate

Front Page Continuation (72) Inventor Richard Dean Twig United States, Minnesota 55144-1000, St Paul, 3M Center (No Address) (72) Inventor Michael Charles Darlington Minnesota 55144-1000, St Paul, 3M Center (Address) None)

Claims (5)

[Claims] 1. An improved test socket for an integrated circuit having a long columnar solder lead, comprising: a base and a first hole for supporting the integrated circuit and accommodating the columnar solder lead. And a contact having elasticity for electrically contacting a solder lead wire of the integrated circuit that extends at least partially into the first hole, and the columnar solder overlaps with the platform. A support plate having a second hole for accommodating the conductor wire, said support plate having a thickness sufficient to support said length of columnar solder wire, thereby preventing damage to said columnar solder wire Test socket modified to do so. 2. The test socket of claim 1, further comprising a cover removably attached to the base, the cover pushing the integrated circuit into contact with the contact. 3. The test socket according to claim 2, further comprising a hinge for attaching the cover to the base. 4. The test socket according to claim 3, further comprising a hooking member for holding a contact state between the cover and the integrated circuit. 5. The platform has legs hanging from the platform toward the base, the legs terminating as protrusions extending substantially perpendicular to the legs, the base interacting with protrusions on the legs. And a wall that allows the leg to move toward the base but not away from the base.
Test socket described in.