Active solid-state devices (e.g. – transistors – solid-state diode – Housing or package – With provision for cooling the housing or its contents
Reexamination Certificate
2001-02-23
2003-04-01
Potter, Roy (Department: 2822)
Active solid-state devices (e.g., transistors, solid-state diode
Housing or package
With provision for cooling the housing or its contents
C257S718000, C257S778000
Reexamination Certificate
active
06541855
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to printed board units, and more particularly to a printed board unit which includes a large scale integration (LSI) package of a land grid array (LGA) type mounted on a printed board with an LGA socket interposed therebetween, and forms a server that is an information processing and communication facility.
A printed board unit forming a server is plugged into a motherboard in consideration of repairs in the event of a failure, and an LSI package is replaceably mounted on a printed board.
In the server, repairs are made with a printed board unit being removed from the server. During the repairs, the server operates with a reduced processing capacity compared with its normal state since the printed board unit is removed from the server. Therefore, it is desirable that the repairs should be made so quickly that a period for which the server operates with the reduced capacity compared with its normal state becomes as short as possible.
Further, like the above-described repairs, the additional installation of an LSI package on the printed board is also performed with a printed board unit being removed from the server. Therefore, it is also desirable that the additional installation of the LSI package should be quickly performed.
Moreover, it is desirable that the repairs should be made and the additional installation should be performed with the lowest possible costs.
2. Description of the Related Art
FIGS. 1 and 2
each show a conventional printed board unit
10
. The printed board unit
10
includes an LGA-type LSI package
20
mounted on a printed board
11
with an LGA socket
30
interposed therebetween. A stiffener
40
is provided on the lower surface of the printed board
11
with an insulating sheet
45
interposed therebetween, and a heat transfer plate
41
that doubles as a cooling fin is provided on the upper surface of the LSI package
20
. The printed board unit
10
further includes nuts
42
, which are tightened so that the heat transfer plate
41
presses the LSI package
20
onto the printed board
11
through a heat transfer sheet
46
by coiled springs
43
. Each of lands
21
of the LSI package
20
is electrically connected to a corresponding one of lands
12
formed on the printed board
11
via a corresponding one of contacts
31
of the LGA socket
30
.
The printed board unit
10
is mounted on a motherboard by being plugged thereinto and is incorporated into a server.
Here, a description will be given of repairs in the event of a failure of the LSI package
20
.
The repairs are made in the following procedure. In step
1
, the printed board unit
10
is removed outside from the server. In step
2
, at the site, the nuts
42
are loosened and removed, and the heat transfer plate
41
is pulled off the bolts
40
a
of the stiffener
40
so that the LSI package
20
, the LGA socket
30
, and the heat transfer plate
41
are apart from one another. In step
3
, the faulty LSI package
20
is replaced with a new LSI package. In step
4
, the LSI socket
30
is positioned on the printed board
11
. In step
5
, the new LSI package is positioned on the LSI socket
30
. In step
6
, the heat transfer plate
41
is combined with the stiffener
40
and the coiled springs
43
are fitted to the bolts
40
a
before the nuts
42
are tightened. In step
7
, the printed board unit
10
is inserted into the server.
Repairs are also made in the above-described procedure in the event of a failure of the LGA socket
30
.
Positioning the new LSI package on the LGA socket
30
requires accuracy, and is troublesome and relatively time-consuming. Therefore, the repairs of failures of the LSI package
20
and the LGA socket
30
are relatively time-consuming.
The additional installation of an LSI package also requires positioning the LSI package on an LGA socket, and therefore, is relatively time-consuming.
At some sites, dust attaches to the lands
21
of the LSI package
20
and the contacts
31
of the LGA socket
30
while the LSI package
20
and the LGA socket
30
are apart from each other so that the reliability of electrical connection between the LSI package
20
and the LGA socket
30
may be impaired.
In the event of a failure of an LSI package or an LGA socket, a new printed board unit may be fitted into the server after a printed board unit including the faulty LSI package or LGA socket is removed from the server, which method dispenses with the removal of the faulty LSI package or LGA socket.
The above-described method dispenses with the replacement of the faulty LSI package or LGA socket, thus realizing quick replacement of a faulty component. However, in order to realize this method, it is necessary to prepare a new printed board unit for replacement for each printed board unit, thus increasing the costs of spare components.
Similarly, in the case of the additional installation of an LSI package, it is necessary to prepare a new printed board unit for the additional installation, thus increasing the costs of spare components.
SUMMARY OF THE INVENTION
It is a general object of the present invention to provide a printed board unit in which the above-described disadvantages are eliminated.
A more specific object of the present invention is to provide a printed board unit which includes a semiconductor device unit as a replacement unit so as to be repaired and reproduced easily in a short time in the event of a failure only by replacing the semiconductor device unit.
The above objects of the present invention are achieved by a printed board unit including a printed board including lands thereon, a semiconductor device unit, and an attachment mechanism for attaching the semiconductor device unit to the printed board, wherein the semiconductor device unit includes: a heat transfer member; a semiconductor device including first and second surfaces parallel to each other, the first surface having lands thereon; and a socket including contacts protruding from first and second surfaces of the socket, the first and second surfaces being parallel to each other, wherein the semiconductor device and the socket are attached to the heat transfer member so that the second surface of the semiconductor device opposes the heat transfer member, and the lands of the semiconductor device are electrically connected to the lands of the printed board unit via the contacts of the socket.
According to the above-described printed board unit, the semiconductor device unit is a replacement unit. In the event of a failure of the semiconductor device, repairs are completed only by removing the semiconductor device unit including the faulty semiconductor device from the printed board unit and replacing the semiconductor device unit by a prepared new semiconductor device unit. Therefore, the positioning of the semiconductor device on the socket is unnecessary. Thus, the printed board unit is repaired in a shorter time than a conventional printed board unit, which requires a semiconductor device and a socket to be apart from each other for repair.
REFERENCES:
patent: 5883788 (1999-03-01), Ondricek et al.
patent: 6325552 (2001-12-01), Brillhart
patent: 7-312242 (1995-11-01), None
patent: 10-135379 (1998-05-01), None
Potter Roy
Staas & Halsey , LLP
LandOfFree
Printed board unit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Printed board unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Printed board unit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3038955