Electrical connectors – Preformed panel circuit arrangement – e.g. – pcb – icm – dip,... – With provision to conduct electricity from panel circuit to...
Reexamination Certificate
1999-11-05
2001-01-30
Paumen, Gary F. (Department: 2833)
Electrical connectors
Preformed panel circuit arrangement, e.g., pcb, icm, dip,...
With provision to conduct electricity from panel circuit to...
C439S066000
Reexamination Certificate
active
06179624
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a land grid array (LGA) connector for electrically connecting a CPU to a printed circuit board, especially an LGA connector combined with a ball grid array technique for simultaneously connecting to the CPU by urging and connecting to the printed circuit board by solder balls.
2. The Prior Art
Land grid array (LGA) connectors are commonly used with IC packages and do not require soldering procedures during engagement between the LGA connector and a related printed circuit board (PCB). Normally, an LGA assembly includes an IC package having a plurality of flat contact pads formed on a bottom surface thereof, a connector having an insulative housing and defining a plurality of passageways therethrough, and a plurality of conductive contacts received in the passageways of the connector. Fastening means comprises a top plate positioned on a top surface of the IC package, a bottom plate positioned onabottom surface of the PCB, and a plurality of sets of aligned holes defined through the PCB. The fastening means is used to configure the assembly. Each set of aligned holes receives a screw therein which engages with a washer and a nut thereby sandwiching the LGA assembly between the top and bottom plates of the fastening means.
U.S. Pat. No. 5,653,598 discloses an electrical contact for use in a connector
30
between mutually opposed electrical interfaces
40
,
99
such as contact pads respectively formed on an IC package
2
and a printed circuit board
9
, as shown in FIG.
10
. The conventional contact comprises a generally planar contact body
10
having first and second major faces
110
,
120
. The body includes a pair of spaced apart spring arms
140
,
150
connected by a resilient bight portion
160
. The spring arms
140
,
150
each have a free end with an outwardly facing edge forming a contact nose
17
,
18
for engaging with the corresponding interface
40
,
99
. Shorting sections
19
,
20
generally extend toward each other from the free ends and are offset such that, upon deflection of the spring arms
140
,
150
toward each other, the shorting sections
19
,
20
overlap and the first major face
110
engages the second major face
120
. Thus, a shortened electrical path is formedbetween the contact noses
17
,
18
when the package
2
is urged against the connector
30
.
With the conventional LGA connector, the shorting sections
19
,
20
may not properly contact each other due to unwanted lateral deflection thereof when the bight of the contact is deformed. Although the inner wall of the passageway receiving the contact may be used to limit the lateral deflection of the shorting sections
19
,
20
, unwanted scraping of the shorting sections
19
,
20
against the inner wall of the passageway may occur thereby adversely affecting the proper overlap of the two shorting sections
19
,
20
. Proper overlap and engagement of the two shorting sections
19
,
20
is difficult to achieve with this structure. Moreover, an additional contact resistance exists between the shorting sections
19
,
20
thereby adversely affecting the signal transmission.
Additionally, the conventional LGA connector is in advance fixed in a motherboard via screws in a pre-assembly procedure. In a final assembly procedure, the screws have to be released first and then fastened for urging the CPU to the LGA connector. Therefore, in the total assembly procedure, the screws have to be fastened, released, and fastened again. This is cumbersome and not accepted by most mother board manufacturers.
Moreover, the contact noses
17
,
18
each have a relatively small contacting surface abutting against the interface
40
,
99
thereby causing a relatively high contacting resistance and affecting the transmission of signals.
It is requisite to provide a new LGA connector for solving the above problems.
SUMMARY OF THE INVENTION
The primary purpose of the present invention is to provide a new LGA contact which has a positioning section for connection to a printed circuit board via a solder ball in advance and a resilient contacting section for connection to a CPU via urging.
Another purpose of the present invention is to provide a new LGA connector which has new LGA contacts each of which may be partially surface mounted to a printed circuit board via a solder ball and partially connected to a CPU by urging.
Still another purpose of the present invention is to provide a new LGA connector having solder balls mounted thereon and having special structure for preventing wicking problem during a soldering procedure.
Further a purpose of the present invention is to provide a new LGA connector which has a special structure for decreasing contacting resistance associated with an external electrical device which urges the LGA connector.
In accordance with one aspect of the present invention, a contact comprises a plate, a positioning section connected to the plate via a first flexible neck and adapted to be mounted by an external solder ball, a contacting section located above and connected to the positioning section via a second flexible neck. The first flexible neck is deformable to absorb a tension originated from the plate. The second flexible neck is deformable to force the contacting section to abut against an external electrical device such as a CPU package when the external electrical device urges the contacting section to electrically connect to the solder ball via the contact.
In accordance with another aspect of the present invention, a connector comprises an insulative housing in which a plurality of passageways are defined. A plurality of contacts are received in the passageways. Each contact comprises an engagement plate firmly retained in the passageway in a vertical manner, a first positioning section connected to the engagement plate via a first neck and maintained in a horizontal position, a second positioning section connected to the first positioning section via an intermediate section and maintained parallel to the first positioning section, and a contacting section connected to the second positioning section via a second neck. The contacting section is located beyond the passageway and a solder ball may be selectively mounted onto either one of the first positioning section and the second positioning section.
REFERENCES:
patent: 5378160 (1995-01-01), Yumibe et al.
patent: 5653598 (1997-08-01), Grabbe
patent: 5984693 (1999-11-01), McHugh et al.
Lin Nick
McHugh Robert G.
Tan Hanchen
Wang Jwomin
Chung Wei Te
Hon Hai - Precision Ind. Co., Ltd.
Paumen Gary F.
LandOfFree
Land grid array connector does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Land grid array connector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Land grid array connector will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2546943