U.S. patent application number 13/412881 was filed with the patent office on 2012-06-28 for integrated semiconductor outline package.
This patent application is currently assigned to Infineon Technologies AG. Invention is credited to Stanley Job Doraisamy, Wae Chet Yong.
Application Number | 20120162924 13/412881 |
Document ID | / |
Family ID | 37873103 |
Filed Date | 2012-06-28 |
United States Patent
Application |
20120162924 |
Kind Code |
A1 |
Job Doraisamy; Stanley ; et
al. |
June 28, 2012 |
Integrated Semiconductor Outline Package
Abstract
A transistor outline package is provided for a semiconductor
integrated device suitable for use in a control module of an
automobile for connection between a printed circuit board and a bus
bar of such a module. The package includes a package housing,
having a first end suitable for mounting to a PCB and which has a
width. The package is also formed with a leadframe which includes a
heat sink and ground plane blade suitable for connection to a bus
bar, a plurality of connector leads suitable for connection to a
PCB and at least one source tab lead suitable for connection to a
module connector of such a control module. The plurality of
connection leads and the source tab lead extend from the first end
of the package housing side by side in the direction along and
within the width of the first end of the package housing.
Inventors: |
Job Doraisamy; Stanley;
(Kuala Lumpur, MY) ; Yong; Wae Chet; (Malacca,
MY) |
Assignee: |
Infineon Technologies AG
Munich
DE
|
Family ID: |
37873103 |
Appl. No.: |
13/412881 |
Filed: |
March 6, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12513906 |
May 7, 2009 |
8169069 |
|
|
PCT/SG06/00379 |
Dec 5, 2006 |
|
|
|
13412881 |
|
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Current U.S.
Class: |
361/719 ;
361/783 |
Current CPC
Class: |
H01L 23/49555 20130101;
H01L 23/49562 20130101; H05K 1/0263 20130101; H05K 2201/10659
20130101; H01L 23/49541 20130101; H01L 2924/0002 20130101; H05K
1/18 20130101; H05K 2201/10166 20130101; H01L 2924/0002 20130101;
H01L 2924/00 20130101; H05K 1/181 20130101 |
Class at
Publication: |
361/719 ;
361/783 |
International
Class: |
H05K 7/20 20060101
H05K007/20; H05K 7/06 20060101 H05K007/06 |
Claims
1. A control module of an automobile comprising: a printed circuit
board (PCB); a bus bar; a plurality of module connectors for
connecting the control module to electronic components of the
automobile; and a semiconductor package disposed between the bus
bar and the PCB, the semiconductor package comprising: a
semiconductor integrated device encapsulated in a package housing
having a first end with a width, and a plurality of leads, each
lead having a first portion adjacent to and extending out of the
package housing, wherein the first portions fit within the width of
the package housing, wherein at least one of the plurality of leads
is a source tab lead and at least one of the plurality of leads is
a connection lead coupled to the PCB, wherein the connection leads
are configured to be attached as a surface mount connection to a
PCB, wherein the source tab lead passes through the PCB as a
through hole connection to a module connector of the plurality of
module connectors.
2. The control module of claim 1, wherein the module connector has
a width substantially greater than a width of any of the first
portions.
3. The control module of claim 1, wherein a heat sink blade extends
from a second end of the package housing, the heat sink blade
disposed between the bus bar and the package housing, the second
end of the package housing being opposite to the first end of the
package housing along a vertical direction.
4. The control module of claim 3, wherein the heat sink blade
comprises a first portion parallel to the package housing and a
second portion parallel to the bus bar, the first portion and the
second portion being orthogonal to each other, wherein the
connection lead bends to one side in a horizontal direction, and
wherein the source tab lead bends in the opposite horizontal
direction.
5. The control module of claim 1, wherein the source tab lead
transitions into a module connector of the plurality of module
connectors.
6. A control module of an automobile comprising: a printed circuit
board (PCB); a bus bar; a semiconductor integrated device
encapsulated in a package housing having a first end with a width,
the package housing disposed between the bus bar and the PCB; a
heat sink blade disposed between the bus bar and the package
housing; a plurality of leads, each lead having a first portion
adjacent to and extending out of the package housing, wherein the
first portions fit within the width of the package housing, wherein
at least one of the plurality of leads is a source tab lead and at
least one of the plurality of leads is a connection lead coupled to
the PCB, wherein the connection leads are configured to be attached
as a surface mount connection to a PCB; and a plurality of module
connectors for connecting the control module to electronic
components of the automobile, wherein the source tab lead passes
through the PCB as a through hole connection to a module connector
of the plurality of module connectors.
7. The control module of claim 6, wherein the source tab lead
transitions into a module connector of the plurality of module
connectors.
8. The control module of claim 6, wherein the heat sink blade
extends from a second end of the package housing.
9. The control module of claim 6, wherein the heat sink blade
comprises a first portion parallel to the package housing and a
second portion parallel to the bus bar, the first portion and the
second portion being orthogonal to each other.
10. The control module of claim 6, wherein the plurality of leads
comprise a first set of connection leads and a second set of
connection leads, wherein the first set of connection leads bend to
one side in a horizontal direction, and wherein the second set of
connection leads bend in the opposite horizontal direction.
11. The control module of claim 6, wherein the connection lead
bends to one side in a horizontal direction, and wherein the source
tab lead bends in the opposite horizontal direction.
12. A control module of an automobile comprising: a printed circuit
board (PCB); a bus bar; a semiconductor integrated device
encapsulated in a package housing having a first end with a width,
the package housing disposed between the bus bar and the PCB; a
heat sink blade disposed between the bus bar and the package
housing, the heat sink blade extending from a second end of the
package housing; and a first connection lead and a first source tab
lead extending away from the first end of the package housing along
a vertical direction, the first connection lead having a first
portion adjacent to the first end of the package housing, wherein
the first connection lead is a surface mount connection to the PCB,
wherein the first source tab lead has a neck portion adjacent to
the first end of the package housing, and wherein a portion of the
source tab lead is a connection to a module connector through a
through hole in the PCB.
13. The control module of claim 12, wherein the neck portion of the
first source tab lead has a width less than the width of the first
end providing space for the first portion of the connection lead,
and wherein the neck portion overlaps within the width of the first
end of the package housing.
14. The control module of claim 12, wherein the neck portion of the
first source tab lead transitions into a module connector, wherein
the module connector has a width greater than the width of the neck
portion of the first source tab.
15. The control module of claim 14, wherein a second portion has a
width substantially greater than the width of the neck portion.
16. The control module of claim 12, further comprising a second
source tab lead, the first and the second source tab leads located
on opposite sides of the first connection lead.
17. The control module of claim 12, wherein the first portion of
the first connection lead and the neck portion of the first source
tab lead extend side by side, wherein a second connection lead
extends away from the first end of the package housing along the
vertical direction, and wherein the first connection lead bends to
one side in a horizontal direction the second connection lead bends
in the opposite horizontal direction.
18. The control module of claim 12, wherein the first portion and
the neck portion extend side by side and the first connection lead
bends to one side in a horizontal direction and the source tab lead
bends in an opposite horizontal direction.
19. The control module of claim 12, wherein the heat sink blade
extends along a surface of a bus bar.
20. The control module of claim 12, wherein the package housing has
a substantially uniform width from the first end to the second end.
Description
[0001] This application is a divisional of patent application Ser.
No. 12/513,906, filed on May 7, 2009, which is a national stage of
international application number PCT/SG06/00379, filed on Dec. 5,
2006, which applications are incorporated herein by reference.
BACKGROUND
[0002] This invention relates to an integrated semiconductor
outline package and refers particularly, but not exclusively, to a
transistor outline package for connection between a printed circuit
board (PCB) and a bus bar of a control module of an automobile.
[0003] Electrical power distribution systems for automobiles,
typically include a control module that provides centralized
control of the electronic components of the automobile. A
conventional control module includes a junction box, which is
commonly referred to as a smart junction box. The junction box
includes a housing that contains one or more layers of PCBs, which
support semiconductor integrated devices. The control module also
includes module connectors to provide electrical connections
between the control module and the electronic components of the
automobile.
[0004] Some of the devices mounted on the PCBs of the control
module generate significant amounts of heat. Such devices are
generally provided in transistor outline (TO) packages so as to
provide heat dissipation and there is an increasing demand for TO
packages which provide high levels of heat dissipation.
[0005] The United States Council for Automotive Research (USCAR)
maintains strict requirements for the mounting of TO packages on a
PCB in such control modules, such as limitations on terminal (pin)
thickness and width, as well as pin to pin pitch and pin row to pin
row pitch, which place restrictions on the leadframe design of TO
packages.
SUMMARY OF INVENTION
[0006] A semiconductor package is provided with a heat sink blade
which extends from an end of the package so as to provide heat
sinking from the package to an external heat sink. The package is
also provided with a set of leads having portions which extend
side-by-side from an opposite end of the package and within a width
measurement of the package. At least one of the leads is a
connection lead suitable for surface mounting on a printed circuit
board and at least one of the leads is a source tab lead suitable
for through mount connection to a module connector or transitions
into such a module connector. The heat sink blade and the set of
leads are formed from the package leadframe. To provide space for
the connection leads within the width measurement, the source tab
lead is formed with a neck portion.
BRIEF DESCRIPTION OF DRAWINGS
[0007] There shall now be described by way of some none limiting
embodiments, the description being with reference to the
accompanying illustrative drawings. In the drawings:
[0008] FIG. 1 is a schematic illustration of a structure of a
typical control module for an automobile;
[0009] FIG. 2 is a front view of an embodiment of a TO package
according to the present invention connected to a PCB;
[0010] FIG. 3 is a side view of the TO package of FIG. 2;
[0011] FIG. 4 is a plan view of the TO package of FIG. 2;
[0012] FIG. 5 is a front view of an embodiment of a TO package
according to the present invention connected to a PCB;
[0013] FIG. 6 is a side view of the TO package of FIG. 5;
[0014] FIG. 7 is a perspective view of the TO package of FIG.
5;
[0015] FIG. 8 is a perspective view of a TO package according to
the present invention connected between a PCB and a bus bar heat
spreader;
[0016] FIG. 9 is a perspective view of the TO package of FIG.
8;
[0017] FIG. 10 is a side view of the TO package of FIG. 8; and
[0018] FIG. 11 is a view of the underside of the TO package of FIG.
8.
DETAILED DESCRIPTION
[0019] FIG. 1 shows schematically a control module for an
automobile, also known as a smart junction box. The control module
comprises a housing (2), within which is housed an electronic
driver (4) comprising multi-layered PCBs on which are mounted
various electronic components which together perform the
functionality of the control module. The electronic driver (4) is
connected to the various electronic components of the automobile
via a fuse and relay PCB (6) on which are mounted various
electronic components which together perform the functionality of
the fuse and relay PCB. A metallic heat spreading bus bar (8) is
located within the housing between the multi-layered PCBs of the
electronic driver (4) and the fuse and relay PCB (6) and acts as a
heat sink and ground plane for the components mounted on at least
the fuse and relay PCB (6). The fuse and relay PCB (6) is connected
to the electronic components of the automobile via a plurality of
module connectors or spade output terminals (10).
[0020] The fuse and relay PCB (6) has a plurality of semiconductor
IC high power MOSFET devices mounted on it. The high power MOSFET
devices generate a lot of heat and so are generally provided in the
form of a transistor outline (TO) integrated package.
[0021] Conventionally separate components are required for making a
connection between the TO package and the module connectors (10)
and for making a connection between the TO package and the bus bar
(8). The TO packages described herein are integrated with a source
tab lead (106, 109, 206) for making a direct connection to or which
transition into a module connector (10) and are integrated with a
bus bar connector (16, 116). The TO packages described herein also
offer the possibility of a combination of through hole and surface
mount connection to a PCB, which provides a very stable mounting,
while meeting the USCAR pitch requirements for the mounting of the
TO packages on the fuse and relay PCB (6).
[0022] One embodiment of a TO package (12), is shown in FIGS. 2 to
4. The TO package (12) is suitable for use in a control module of
an automobile, for example, of the type described above in relation
to FIG. 1. The TO package (12) is suitable for connection between a
printed circuit board (PCB), for example a fuse and relay PCB (6),
and a bus bar (8) of such a module. The TO package (12) comprises a
leadframe and a semiconductor integrated device (15) encapsulated
together in a package housing (14) to form the package (12). The
package housing (14) will generally be plastic molded over the
device and leadframe.
[0023] In the embodiments of the invention described herein, the
width (w) of the package housing (14) is marked on the Figures and
is the largest dimension of the package housing extending
substantially parallel to the PCB (6) on which the package is
mounted. The width measurements referred to herein extend
substantially parallel to the width (w) marked in the Figures. If a
pair of parallel planes are constructed, one at either end of the
width measurement (w), so that the width dimension is normal to
both of the planes, the phrase `extending within the width` is
defined as extending within the space bounded by these two planes.
A first direction is also defined herein, as the general direction
in which the first portions of the connection leads (18b) and the
neck portion or portions of the source tab lead or leads (106, 109,
206) extend side by side. In the embodiments described herein, the
first direction is substantially parallel to the width dimension,
and for the purpose of illustration is marked on FIG. 9, as
direction (D). In the embodiments described herein the width (w) of
the package housing is substantially the same from the upper end
(14a) to the lower end (14b) of the package housing.
[0024] The TO package (12) has a leadframe, generally formed from a
planar blank which is suitably stamped and folded. The leadframe is
encapsulated with a semiconductor integrated device (15), as is
well known in the art. Connector leads (18) extend from a first
lower end (14b) of the package housing, each having first portions
(18b) adjacent to the first end of the package housing. In
addition, a source tab lead (106) extends from the first end (14b)
of the package housing. A heat sink and ground plane blade (16)
extends from a second end (14a) of the package housing. In the
embodiment of FIGS. 2 to 4, the first and second ends of the
package housing are opposite ends of the package housing. The
source tab lead (106) is formed with a neck portion (106a) which
has a width less than the width (w) of the first end (14b) of the
package housing. This provides space for the first portions (18b)
of the connection leads (18) and for the neck portion (106a) of the
source tab lead (106) to depend side by side from the first end
(14b) of the package housing within the width of the package
housing, as is shown particularly in FIG. 2.
[0025] The TO package is mounted on the upper side of the fuse and
relay PCB (6) with the source tab lead (106) connecting through a
slot in the PCB (6) to a module connector (10) which extends below
the PCB (6) and out of the control module housing (2). Thus the TO
package (12) is provided with a source tab lead (106) suitable for
through hole connection to a module connector (10) through the PCB
(6).
[0026] The package housing (14) has a uniform width (w) and the
leadframe, or at least a blank from which the leadframe is formed
has a uniform width (w').
[0027] The leadframe of the TO package (12) forms a plurality of
leads (18, 106), which extend from the package housing (14), each
lead having a first portion (18b, 106a) adjacent to and depending
from the lower end of the package housing so that these first
portions (18b, 106a) fit within the width (w) of the first end of
the package housing. One of the leads (106) is the source tab lead
suitable for connection to a module connector (10) and the other
leads (18) are connector leads suitable for connection to the PCB
(6).
[0028] A heat sink blade (16) is formed from the leadframe of the
package (12) and acts to dissipate heat from the high power MOSFET
device (15) encapsulated in the package (12) as well as providing a
ground plane connection. The heat sink blade (16) extends upwardly
from the upper second end (14a) of the package housing (14). When
the TO package (12) is mounted on the fuse and relay PCB (6), the
end of the heat sink blade (16) remote from the package housing
(14) contacts the bus bar (8) of the control module. In this way
heat is dissipated from the package (12), along the heat sink blade
(16) to the bus bar (8).
[0029] The source tab lead (106) is also formed from the package
leadframe and provides an electrical connection to the MOSFET
device (15) of the package (12) and extends from the lower first
end (14b) (opposite to the upper end (14a)) of the package housing
(14). The module connector (10) which has a width similar to the
width of the package housing (14) extends laterally offset to and
below the package and is connected to the end of the source tab
lead (106) remote from the package housing (14). In order to
provide space for the plurality of leads (18), the source tab lead
(106) is formed with a reduced width, as compared to the width (w)
of the package housing (14) and the width of the module connector
(10). The source tab lead (106) has a neck portion (106a) which
extends downwardly from the lower end (14b) of the package housing.
The source tab lead (106) then bends through 90 degrees to form a
second part (106b) which extends along the upper surface of the
fuse and relay PCB (6) laterally of the first direction. It then
bends through a further 90 degrees to form a third part, which
extends substantially parallel, but laterally offset, to the first
part and extends through a slot in the fuse relay PCB (6). The
third part of the source tab lead (106) is a through hole connected
to the source tab (10), which forms the module connector.
[0030] Thus, the package (12) has a source tab lead (106) which is
suitable for connection at its end remote from the package housing
(14) to a module connector (10). The module connector (10) extends
below and yet within the width (w) of the package housing. Thus,
the first portions (18b) of the connection leads (18) depend from
the first end (14b) of the package housing into a space to the side
of the neck portion (106a) of the source tab lead (106) below the
first end (14b) of the package housing and above the module
connector (10). In this way the first portions (18b) of the
connection leads (18) and the neck portion (106a) of the source tab
lead (106) extend side by side in a line within the width (w) of
the package housing (14). This side-by-side arrangement enables the
integrated TO package to meet the pin to pin pitch and pin row to
pin row pitch requirements of USCAR (mentioned above).
[0031] In the embodiment of the present invention shown in FIGS. 2
to 4, the plurality of connection leads (18) are suitable for
drain, gate and other logic connections between the MOSFET device
(15) of the package (12) and the fuse and relay PCB (6) by SMD
mounting. The connection leads (18) are formed from the package
leadframe and are designed to make suitable electrical connections
to the device (15) encapsulated within the package (12), as is well
known in the art. These leads (18) have a first portion (18b)
extending downwardly of the lower first end (14b) of the package
housing (14). Each first portion transitions via a 90 degree bend
into a second portion (18a) which extends laterally to the first
direction along the upper surface of the PCB (6) so facilitating
SMD mounting of the TO package onto the fuse and relay PCB (6). As
can be seen in FIG. 3, the second portions (18a) of the connection
leads bend to one side so as to extend laterally of the first
direction.
[0032] Another embodiment of the TO package according to the
present invention is shown in FIGS. 5 and 6, with like parts shown
by like numerals. The main difference between the embodiment of
FIGS. 2 to 4 and that of FIGS. 5 and 6 is the configuration of the
leads. In the embodiment of FIGS. 5 and 6 there are two source tab
leads (109) one to each side of a plurality of connector leads
(18).
[0033] In the embodiment of FIGS. 5 and 6, a pair of source tab
leads (109) are formed from the package leadframe and extend from
the lower first end (14b) (opposite to the upper second end (14a))
of the package housing (14). A common module connector (10) which
again has a width similar to the width of the package (12) is
connected to the ends of the source tab leads (109) remote from the
package housing (14). The source tab leads (109) and module
connector (10) can be connected by dual source wire bonding so as
to form a through hole mounting for the package (12) on the PCB
(6). In order to provide space for the plurality of leads (18), a
space is provided between the pair of source tab leads (109). In
this embodiment source tab leads (109) and the module connector
extend in the same plane, downwardly from the lower first end (14b)
of the package housing (14).
[0034] The spaced source tab leads (109) enable the leadframe of
the package (12) to be formed with a plurality of connection leads
(18) that extend from the lower end (14b) of the package housing,
without any of the leads extending beyond the width (w) of the
package (12). That is, the source tab leads (109) which are formed
as neck portions and the first portions (18b) of the plurality of
leads (18) extend side-by-side from the lower end (14b) of the
package, along the width (w) of the package, but not beyond. This
side-by-side arrangement enables the integrated TO package (12)
shown in FIGS. 4 and 5 to meet the pin to pin pitch and pin row to
pin row pitch requirements of USCAR (mentioned above). The source
tab leads (109) and the first portions (18b) of the connector leads
(18) extend side by side, preferably along a line in the first
direction.
[0035] Again, the plurality of connection leads (18) are suitable
for drain, gate and other logic connections between the MOSFET
device (15) encapsulated within the package (12) and the fuse and
relay PCB (6) by SMD mounting. The connection leads (18) are formed
from the package leadframe and are designed to make suitable
electrical connections to the encapsulated device (15), as is well
known in the art. These leads (18) have a first portion (18b)
extending downwardly of the lower end (14b) of the package housing.
The first portions (18b) of the connection leads and the neck
portions (109) of the source tab leads extend side by side in the
first direction. In FIG. 5, the first direction is in the plane of
the paper substantially parallel to the width dimension and in FIG.
6 it extends normally to the plane of the page. Each first portion
(18b) transitions into a second portion (18a) which extends
laterally of the first direction, along the upper surface of the
PCB (6) so facilitating SMD mounting of the TO package onto the
fuse and relay PCB (6).
[0036] Thus, the source tab leads (109) are formed as neck portions
having a width, and a combined width less than the width (w) of the
package housing and less than the width of the module connector
(10). This provides space for the first portions (18b) of the
connector leads (18) and the source tab leads (109) to depend side
by side from the lower end (14b) of the package housing within the
width (w) of the package housing (14).
[0037] As is shown in FIG. 7, the leads (18) can be bent so as to
extend in opposing directions, laterally of the first direction so
as to enable high stability SMD type mounting on the PCB (6). In
FIG. 7 a first set of the connection leads (the lead (18) extending
to the left in FIG. 7) bend to one side so as to extend laterally
in a first direction along the surface of the PCB (6) and a second
set of the connection leads (the two leads (18) extending to the
right in FIG. 7) bend in a direction opposite to said first side
along the surface of the PCB (6).
[0038] A further embodiment of the present invention is shown in
FIGS. 8 to 11, with like parts shown with like numerals to the
first embodiment. The main differences between the first and third
embodiments are the mounting of the head sink blade (116) on the
bus bar (8) and the configuration of the source tab lead (206) and
module connector (10).
[0039] As shown in FIG. 8, this embodiment of the TO package (12)
is mounted on the upper side of the fuse and relay PCB (6) with the
source tab (10) extending below a slot in the PCB (6) so that the
source tab (10) extends below the PCB (6) and out of the control
module housing (2), so as to form a module connector. The heat sink
blade (116) which is formed from the package leadframe, has a first
portion which extends upwardly from the upper second end (14a) of
the package housing. The first portion transitions into a second
portion of the heat sink blade through a 90 degree bend, so that
the second portion of the heat sink blade (116) extends parallel to
and along the lower surface of the bus bar (8). The second portion
of the heat sink blade is formed with a through hole (17) which
enables connection to the bus bar (8) via a screw (26). The screw
(26) passes through a hole in the bus bar (8) and through the hole
(17) so as to form a rigid connection between the heat sink blade
(116) and the bus bar (8). This provides improved heat dissipation
from within the package housing (14), along the heat sink blade
(116) to the bus bar (8).
[0040] Again the source tab lead (206) is also formed from the
package leadframe and provides an electrical connection to the
MOSFET device (15) encapsulated within the package (12) and extends
from the lower first end (14b) of the package housing. The module
connector (10) which has a width similar to the width of the
package housing (14) is connected to or is formed integrally with
the end of the source tab lead (206) remote from the package
housing. In order to provide space for the plurality of connection
leads (18), the source tab lead (206) is formed with a neck portion
(206a) of reduced width, as compared to the width of the package
housing (14) and the width of the module connector (10). The width
dimensions are measured in a direction substantially parallel to a
first direction (D) identified in FIG. 9. The source tab lead (206)
has a first neck portion (206a) which extends downwardly from the
lower end (14b) of the package housing (14). The source tab lead
(206) then bends through 90 degrees to form a second part (206b)
which extends along the upper surface of the fuse and relay PCB
(6), laterally to the first direction (D). The second part (206b)
then transitions into a first part of the module connector (10),
which has a similar width as the package housing (14) and which
continues to extend along the upper surface of the PCB (6). The
first part of the module connector (10) then bends through 90
degrees to form a second part, which extends substantially
parallel, but laterally offset, to the first part of the source tab
lead (206) and extends through a slot in the fuse and relay PCB (6)
and below the PCB (6).
[0041] The reduced width neck portion (206a) of the source tab lead
(206) enables the leadframe of the package (12) to be formed with a
plurality of connection leads (18) that extend from the lower first
end (14b) of the package housing, without the leads extending
beyond the width (w) of the package housing (14). That is, the
source tab lead neck portion (206a) and first portions (18b) the
plurality of leads (18) extend side-by-side from the lower end
(14b) of the package housing, along the width of the package
housing, but not beyond, as is shown particularly in FIG. 9. This
side-by-side arrangement enables the integrated TO package
according this embodiment to meet the pin to pin pitch and pin row
to pin row pitch requirements of USCAR (mentioned above).
[0042] The neck portion (206a) of the source tab lead (206) and the
first portions (18b) of the connection leads (18) extend side by
side, preferably along a line. In FIG. 9, the leads extend side by
side in a first direction aligned with the arrow marked (D), and
substantially parallel to the width measurement (w). In FIG. 10 the
first direction extends perpendicularly of the plane of the paper,
extending from the shaded area (A) where lead portions (206a, 18b)
overlap.
[0043] The plurality of connection leads (18) are suitable for
drain, gate and other logic connections between the MOSFET device
(15) encapsulated within the package (12) and the fuse and relay
PCB (6) by SMD mounting. The leads (18) are part of the package
leadframe and are designed to make suitable electrical connections
to the encapsulated device (15), as is well known in the art. These
leads (18) have a first portion (18b) extending downwardly of the
lower end (14b) of the package housing. Each first portion
transitions via a 90 degree bend into a second portion which
extends along the upper surface of the PCB (6), laterally to the
first direction (D) so facilitating SMD mounting of the TO package
onto the fuse and relay PCB (6). In this third embodiment, the
leads (18) bend in the opposite direction to the source tab lead
(206). Both the connection leads (18) and the source tab lead (206)
bend so as to extend laterally of the first direction (D).
[0044] In the embodiment of FIGS. 8 to 11, the source tab (206) is
formed with a neck portion (206a) adjacent to the first end (14b)
of the package housing (14). This neck portion (206a) has a width
less than the width (w) of the package housing (14) and less than
the width of the module connector (10). This provides space for the
first portions (18b) of the connector leads (18) and the neck
portion (206a) of the source tab lead (206) to depend side by side
from the first end of the package housing, within the width of the
package housing (14).
[0045] A control module of an automobile, of the type described in
relation to FIG. 1, has a housing (2) containing at least one PCB
and at least one metallic bus bar (8) and comprises a plurality of
module connectors (10) for connecting the control module to
electronic components of such an automobile. The control module may
additionally comprise at least one TO package according to any of
the embodiments of FIGS. 2 to 11, in which, for each TO package,
the heat sink blade (16, 116) is connected to the or one of the bus
bars (8) so as to dissipate heat from the package (12), the
connector leads (18) are connected to the or one of the PCBs and
the source tab lead (106, 109, 206) is connected to or transitions
into one of the module connectors (10).
[0046] In the embodiments described in relation to FIGS. 1 to 11,
the or each source tab (106, 109, 206) includes a relatively narrow
portion, the neck or first portions (106a, 109a, 206a), near to the
package housing (14) for connection to a wider module connector
(10) further away from the package housing (14). The relatively
narrow portion can be connected to a module connector (10) via
through hole connection, e.g. via a slot in the printed circuit
board (6). Alternatively, as shown in the embodiment of FIGS. 8 to
11, the source tab (206) can transition into the module connector
(10), which module connector then passes through the PCB (6). The
relatively narrow portion (106a, 109a, 206a) enables some overlap
in the width dimension between the first portions (18b) of the
connector leads (18) and the relatively narrow portions (106a,
109a, 206a) of the source tab lead. For example in FIG. 3, the
narrow portion (106a) is behind the first portions of the
connection leads (18) and so these overlap in the width direction,
i.e., in a direction normal to the plane of the paper in FIG. 3. In
FIG. 6, the first portions of the connection leads (18) and one of
the source tab leads are behind the other of the source tab lead
(109a), and so again these overlap in the width direction, normal
to the plane of the paper in FIG. 6.
* * * * *