PC card assembly and method of assembling the same

Disclosed is an improved method of forming a two-storied type of PC card connector assembly. It comprises the steps of: attaching one card connector to one side of a printed circuit board; soldering the soldering tails of the signal terminals to the signal circuit pattern formed on the one side of the printed circuit board, and the soldering tails of the ground terminals to the through-holes made in the printed circuit board; attaching the other card connector to the other side of the printed circuit board (no ground terminal piece attached thereto); soldering the soldering tails of the signal terminals to the circuit pattern formed on the other side of the printed circuit board; press-fitting a separate ground terminal piece in the other card connector; and soldering the soldering tails of the ground terminal piece to the ground circuit pattern formed on the other side of the printed circuit board.

FIELD OF THE INVENTION 
The present invention relates to a PC card connector assembly and a method 
of assembling a PC card connector assembly comprising a printed circuit 
board and a PC card connector on each side of the printed circuit board, 
each PC card connector having signal terminals and ground terminals. 
DESCRIPTION OF THE PRIOR ART 
The signal terminals and ground terminals of known PC card connectors 
typically have solder tails formed in a right angle configuration and 
positioned at the rear end of the PC card connector such that the ends of 
the solder tails are directed to and in contact with circuit traces on the 
underlying printed circuit board. These solder tails are often fixed to 
the circuit board by dip-soldering whereby they are inserted in 
through-holes made in the circuit board and then soldered. 
In applications where two PC card connectors are used in a stacked or "dual 
port" configuration, the circuit board uses a relatively large area 
allotted to the layout of the through-holes for accommodating each row of 
solder tails (often two rows of tails for the signal terminals and one for 
the ground terminals) for each connector. One attempt to solve the problem 
of occupying such a large area with through-holes is to place one PC card 
connector on one side of the circuit board and a second PC card connector 
on the other side of the circuit board. In assembling such an arrangement, 
however, there are some tradeoffs due to the layout that must be 
considered. Specifically, since the solder tails of the signal and ground 
terminals are arranged in at least two different rows, alignment of the 
solder tails with respect to the circuit pattern formed on the circuit 
board is difficult to inspect and correct. Particularly, visually 
inspecting and correcting the alignment of the solder tails positioned 
toward the inside of the assembly is more difficult than inspecting and 
correcting the solder tails positioned toward the outside of the assembly. 
SUMMARY OF THE INVENTION 
One object of the present invention is to provide a dual port PC connector 
assembly occupying a relatively small area on the printed circuit board, 
while allowing and facilitating visual inspection and correction of the 
alignment of the solder tails of the signal and ground terminals. 
To attain this and other objects, a PC card connector assembly is improved 
according to the present invention in that it comprises: a first PC card 
connector for mounting to a printed circuit board including signal 
terminals having surface mount solder tails adapted to be surface mounted 
to a first side of the circuit board; a first ground piece mounted on the 
first PC card connector and including through-hole solder tails adapted to 
be mounted within holes in the circuit board; a second PC card connector 
for mounting to the circuit board including signal terminals having 
surface mount solder tails adapted to be surface mounted to an opposite 
side of the circuit board; and a second ground piece for mounting on the 
second PC card connector and including surface mount solder tails adapted 
to be mounted to the surface of the opposite side of the circuit board. 
Further according to the invention, a method of forming a PC card connector 
assembly is disclosed, the PC card connector assembly including a printed 
circuit board and first and second PC card connectors fixed to opposite 
sides of the circuit board, each PC card connector having signal terminals 
and ground terminals, the method of forming the assembly comprising the 
steps of: attaching the first PC card connector to one side of the printed 
circuit board, the solder tails of the signal terminals of the first PC 
card connector being of surface mount type, and the solder tails of the 
ground piece of the first PC card connector being of dip-soldering type; 
soldering the solder tails of the signal terminals of the first PC card 
connector to the signal circuit pattern formed on the surface of the one 
side of the circuit board; soldering the solder tails of the ground piece 
of the first PC card connector within the through-holes of a ground 
circuit of the printed circuit board; attaching the second PC card 
connector to an opposite side of the circuit board, the solder tails of 
the signal terminals of the second PC card connector being of surface 
mount type; soldering the solder tails of the signal terminals of the 
second PC card connector to the signal circuit pattern formed on the 
surface of the other side of the circuit board; assembling a ground 
terminal piece onto the second PC card connector, the solder tails of the 
ground terminal piece being of surface mount type; and soldering the 
solder tails of the ground terminal piece of the second PC card connector 
to a ground circuit pattern formed on the surface of the opposite side of 
the circuit board. 
Soldering the solder tails of the signal terminals and soldering the solder 
tails of the ground piece of the first PC card connector on the first side 
of the circuit board can be effected simultaneously by reflow soldering, 
for example. 
The surface mount solder tails of the signal and ground terminals of the 
second PC card connector are soldered to the circuit pattern formed on the 
opposite side of the circuit board, thus reducing the total area occupied 
on the circuit board by the dual port PC card assembly. In additional, 
visual inspection of the solder tails of the signal terminals of the first 
PC connector can be performed without obstruction by the solder tails of 
the ground terminals. The solder tails of the ground terminals can also be 
inspected from the opposite side without obstruction. Visual inspection of 
the solder tails of the signal terminals of the second PC connector can be 
performed without obstruction by the solder tails of the ground terminals, 
which are soldered subsequent to the signal terminals. The solder tails of 
the ground terminals can also be inspected easily, i.e., without visual 
obstruction, after it is assembled on the second PC card connector.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings and first to FIGS. 1 through 3, a PC card 
connector assembly 1 comprises a printed circuit board 2 and first and 
second PC card connectors 3 and 4 fixed to front and rear sides 2a and 2b 
of printed circuit board 2, respectively. Printed circuit board 2 has a 
receptacle connector 5 for connecting the printed circuit board to a group 
of wires or other electrical boards via an associated plug connector (not 
shown). 
PC card connector 3 mounted on the front side of the printed circuit board 
includes right angle-configured signal terminals 8 which have two rows of 
contacts 7 located in a card slot 6 of a connector housing 10 of PC card 
connector 3. Surface mount solder tails 11 of signal terminals 8 are 
adapted to be surface mounted to a conductive pattern 12 of a signal 
circuit (not shown) formed on the surface of front side 2a of printed 
circuit board 2. The connector housing 10 has a ground terminal piece 9 
mounted thereto. Right angle-configured solder tails 13 of ground piece 9 
are adapted to be dip-soldered within through-holes 14 of a ground circuit 
(not shown) on front side 2a of circuit board 2. 
PC card connector 4 mounted on rear side 2b of printed circuit board 2 
includes right angle-configured signal terminals 17 which have two rows of 
contacts 16 located in a card slot 15 of a connector housing 19. Surface 
mount solder tails 20 of signal terminals 17 are adapted to be 
surface-mounted to a conductive pattern 21 of a signal circuit formed on 
the surface of rear side 2b of circuit board 2. Connector housing 19 has a 
ground terminal piece 18 mounted thereon. Ground piece 18 comprises a 
lateral base, mount projections 26 integrally connected to one side of the 
lateral base, each projection having a contact 25 integrally connected 
thereto, and right angle-configured solder tails 22 integrally connected 
to the other side of the lateral base. Connector housing 19 has insertion 
slots with notched edges 24 in opposite sides of the slots, thus 
permitting the insertion of mount projections 26 of ground piece 18 into 
connector housing 19. Surface mount solder tails 22 of ground terminal 
piece 18 are adapted to be surface mounted to a conductive pattern 23 of a 
ground circuit (not shown) also formed on the surface of rear side 2b of 
circuit board 2. 
Now, the method of assembling the PC card connector assembly will be 
described. The method comprises the steps of: placing the first PC card 
connector 3 on a first side 2a of the printed circuit board 2, inserting 
the through-hole solder tails 13 of ground piece 9 in the through-holes 14 
of the circuit board, and placing the surface mount solder tails 11 of the 
signal terminals 8 on the conductive pattern 12 formed on the surface of 
first side 2a of the circuit board. The soldering of both sets of solder 
tails can be effected simultaneously, for example by reflow soldering. 
Prior to soldering, the location and alignment of the surface mount solder 
tails 11 relative to the conductive pattern 12 is visually inspected so 
that misalignments and other problems with the solder tails can be 
detected and corrected before soldering. No visual obstructions interfere 
with the inspection of the solder tails 11 since they are located on the 
outside of the assembly, thereby facilitating visual inspection thereof. 
Also, visual inspection of the through-hole solder tails 13 of ground 
piece 9 can be performed from the opposite side 2b of circuit board 2, 
i.e. looking for the presence of a tail within or protruding from the 
through-hole itself, since no connector has been placed over the tails to 
obstruct the inspection. 
After fixing the first PC connector 3 to the first side 2a of circuit board 
2, a second PC connector 4 is placed on the second or opposite side 2b of 
the circuit board, and the required solder connections are made. The 
second PC connector 4 is designed to permit the subsequent assembly of 
separate ground piece 18 to the connector housing 19. 
After placing the second PC connector 4 on the second side of the circuit 
board (prior to assembling the separate ground piece), the alignment of 
surface mount solder tails 20 of signal terminals 17 relative to a 
conductive pattern 21 formed on the surface of the second side of the 
circuit board is visually inspected, and misalignments and other problems 
with the signal terminal solder tails 20 can be detected and corrected. 
The inspection and correction of misalignments of the solder tails can be 
performed without difficulty because there are no obstacles that 
interfere. After checking the signal terminal solder tail alignment, the 
solder tails are soldered to the conductive pattern 21, for example by 
reflow soldering. After soldering, visual inspection of the solder joint 
can also be made. 
After assembling the second connector to the second side of the circuit 
board, the ground piece 18 is press-fit into the connector housing 19 of 
the second PC card connector so that solder tails 22 of the ground piece 
are in contact with the corresponding portions of a conductive pattern 23 
of a ground circuit formed on the second side of the circuit board. Visual 
inspection of the relative positioning between solder tails 22 and the 
corresponding portions of conductive pattern 23 of the ground circuit can 
be made easily because the interface is visually free of any obstacles. 
After visual inspection is performed on the positioning of the tails, the 
tails are soldered to the ground circuit. After soldering, the solder 
joints can be inspected as well. 
The PC card connector assembly according to the present invention results. 
It is understood that the invention may be embodied in other specific forms 
without departing from the spirit or central characteristics thereof. The 
present examples and embodiments, therefore, are to be considered in all 
respects as illustrative and not restrictive, and the invention is not to 
be limited to the details given herein.