Electrical connectors – With coupling movement-actuating means or retaining means in... – For dual inline package
Reexamination Certificate
2000-11-03
2001-11-27
Ta, Tho D. (Department: 2833)
Electrical connectors
With coupling movement-actuating means or retaining means in...
For dual inline package
C439S330000
Reexamination Certificate
active
06322384
ABSTRACT:
FIELD OF THE INVENTION
This inventions relates generally to a socket suitable for removably receiving an electrical part such as an integrated circuit (IC) having a plurality of terminals of the LGA or BGA, etc., type and more particularly to a socket for use in a burn-in test of the IC.
BACKGROUND OF THE INVENTION
Various tests are conducted for the purpose of identifying and discarding those IC packages that do not meet the required specifications for newly manufactured semiconductor integrated circuits. The burn-in procedure tests the IC's heat resistance properties by causing them to perform for a certain period of time at high temperature, thereby making it possible to cull out those that do not meet the required specifications. In a burn-in test, the IC is mounted on the socket that has been prepared exclusively for that purpose and the socket is in turn mounted on a printed circuit substrate for placement in a heating oven. Various kinds of sockets have been proposed for use in burn-in tests of IC packages of the LGA (Land Grid Array) or BGA (Ball Grid Array) types which have become popular in recent years. Basically, such sockets have a base member made of an insulating material and have a plurality of contact members that correspond to the terminals arranged on one surface of the IC. The contact members are arranged on the seating surface of the socket to correspond to each terminal of the IC to be brought in touch with the same when the IC has been placed on the seating surface. In a typical kind of socket, a cover is provided for holding the IC on the seating surface, with the IC being held on and removed from the seating surface by moving the cover up and down.
With reference to
FIGS. 13 and 14
, one such prior art socket has one side of a cover
142
rotatably supported on a base
141
. When cover
142
is opened as shown in
FIG. 14
, IC
100
is placed onto seating surface
141
a
and cover
142
is closed by means of an automatic unit, not shown in the drawing. A hook
143
is engaged with a latch on base
141
to maintain cover
142
in a closed position. IC
100
on seating
141
a
is compressed from above by a compression surface
142
a
inside cover
142
, with the terminals of the IC brought into engagement with the tip of respective contact members.
A problem with this type of socket is that when closing cover
142
, compression surface
142
a
approaches the base in a way which is inclined Is relative to IC
100
with a result that a bias load is applied to the IC. This biased load can damage the IC itself and, at the same time, can result in an uneven compressive force of the contact elements
144
against the terminals of the IC. In addition, the construction of the automatic unit for the switching action of cover
142
is complicated.
Another type of prior art socket is equipped with a mechanism for the vertical movement of the cover member relative to the base member and a latch that opens or closes in linkage with the movement of the cover. It is generally the case that the latch opens when the cover member is lowered, thereby making it possible for the IC to be placed on the seating surface of the base and closes when the cover member is elevated, thereby making it possible for the IC on the seating surface to be held from above.
This type of socket is subject to the following limitations:
(1) The latch needs to have its holding portions extend onto the upper surface of the IC when it is closed and recede from the upper surface of the IC hen it is opened. In order to realize this mechanism, usually a latch and a driving mechanism therefor are arranged around the seating surface of the IC. Because of this, there is a tendency to increase the external size of the socket.
(2) This type of socket for use in burn-in tests has a comparatively large number of parts requiring much time for its assembly.
(3) In this type of socket, the contact members have a curved part pressed against the terminals of the IC with a spring force based on the bending of the curved part when they are pressed. Along with an ever-increasing density of the IC terminals, there is a concomitant demand for the socket to have a contact member with high connective reliability.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide a socket whose outside shape is comparatively small relative to the size of the IC that is to be tested. Another object of the invention is the provision of a socket which is easily and quickly assembled. Still another object of the invention is the provision of a socket having increased reliability of contact engagement of contact members with the terminals of the IC.
The invention relates to a socket for use with an IC having a plurality of terminals on at least one surface thereof. A socket made according to the invention has a seating surface for the IC on an adaptor received on a base with the adaptor being provided in such a way as to have a plurality of contact member receiving holes on the seating surface. The tips of a plurality of contact members corresponding to the terminals of the IC are received through the contact member receiving holes of the adaptor, thereby establishing contact with each terminal of the IC that has been placed on the seating surface. The IC on the seating surface is held by means of a rotary latch having a shaft fixed to the base. The latch has an open position for placement of the IC on the seating surface of the adaptor and a closed position for holding the IC on the seating surface from above the IC. The socket has a cover arranged over the base and a linking member that links the cover and the latch. The cover is supported for movement between a first position which is close to the base and a second position which is removed from the base. The linking member opens the latch when the cover is at the first position and closes the latch when the cover is at the second position.
In a preferred embodiment of the invention, the rotary shaft of the latch is positioned below the seating surface of the adaptor. The cover preferably is normally biased away from the base to its second position. In this connection, preferably the straight line distance between the connecting point of the linking member and the latch and the rotary shaft of the latch varies in conformity with the position of the cover. In a specific example, the connecting point is guided by a slot formed in the latch which is elongated generally in the direction of the rotary shaft. Preferably, a guide is provided on the base so that the connecting point will be guided to a position which is close to the rotary shaft of the latch when the latch is opened and to a position which is away from the rotary shaft of the latch when the latch is closed. The base preferably has four sides, with a latch being provided adjacent to two opposed sides. It is desirable for the adaptor to comprise an assembly having a fixed mounting block, a movable adaptor member and spring members. The mounting block is fixed to the base for holding a plurality of contact members. The adaptor member has a seating surface for an IC device and is movably disposed on the mounting block, the adaptor member receiving the plurality of contact members within the seating surface and being supported in such a manner as to be in contact with or separated from the mounting block and the spring members bias the adaptor member in a direction away from the mounting block.
The plurality of contact members each has a tip part that contacts a respective terminal of a semiconductor device placed on the seating surface and a curved part that provides a compressive force to the tip part against the terminal, some of the plurality of contact makers having the curved parts arranged to extend in a first direction and others having the curved parts arranged to extend in a second direction. Preferably, approximately one half of the plurality of contact members have their curved parts arranged to extend in the first direction and approximately the remaining half have the curved part arr
Baumann Russell E.
Ta Tho D.
Telecky , Jr. Frederick J.
Texas Instruments Incorporated
LandOfFree
Electrical socket apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrical socket apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrical socket apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2583063