US 6,386,890 B1Granted

Printed circuit board to module mounting and interconnecting structure and method

AssigneeInternational Business Machines Corporation

InventorsAnilkumar Chinuprasad Bhatt, William Louis Brodsky, Benson Chan

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Abstract

The present invention provides a method and structure for connecting a module to a printed circuit board, wherein a substantially rigid interposer having resilient conductors is disposed between a module and a printed circuit board. A clamping means urges the module and printed circuit board toward each other with compressive force upon an interposer positioned therebetween, preferably causing the module and printed circuit board to deform and thereby align their electrical contacts with the surfaces of the interposer. The interposer further comprises a plurality of apertures, each aperture further having a deformable resilient conductor means for connecting a module contact to a PCB contact. The conductor is deformable in shear, which may travel and, therefore, makeup the CTE dimensional mismatch between the module and the PCB. The conductors are detachable, electrically connecting the module and PCB contacts without the requirement of solder or other permanent means.

Claims22

Dependent claims

A printed circuit board to module mounting and interconnecting structure comprising:

a. a printed circuit board having a top surface;
b. a plurality of electrical contacts on said printed circuit board top surface;
c. an interposer having upper and lower surfaces;
said interposer lower surface positioned on said printed circuit board electrical contacts;
d. said interposer further defining a plurality of apertures projecting from said upper surface to said lower surface, each of said apertures aligned with one of said contacts;
e. a module having a bottom surface, said bottom surface having a plurality of electrical pads, said pads positioned on said interposer upper surface, each pad aligned with one of said apertures;
f. a plurality of deformable resilient electrical conductors having top and bottom ends, each of said conductors disposed within one of said apertures with each said conductor top end pressing against one said aligned pad and each said conductor bottom end pressing against one said aligned contact, each of said conductors thereby compressed and exerting an upward normal force of at least about 30 grams against said pad and a downward normal force of at least about 30 grams against said contact, said conductor thereby electrically connecting said engaged pad to said engaged contact;
and
g. a clamping means connected to said printed circuit board and said module, said clamping means applying force to said printed circuit board in an upward direction and thereby forcing said contacts against said conductor bottom ends and said interposer lower surface, said clamping means further applying force to said module in a downward direction and thereby forcing said pads against said conductor top end and said interposer upper surface;
wherein said conductor may deform laterally responsive to lateral movement of said printed circuit board relative:
to said module and maintain the upward normal force of at least 30 grams and the downward normal force of at least 30 grams.

8 more elements

A method for mounting and interconnecting a printed circuit board to a module, comprising the steps of:

a. providing a printed circuit board having a top surface with a plurality of electrical contacts;
b. providing an interposer having upper and lower surfaces and a plurality of apertures projecting from said upper surface to said lower surface;
c. providing a plurality of deformable resilient electrical conductors having top and bottom ends, each of said conductors disposed within one of said apertures, each of said top ends projecting above said interposer top surface and each of said bottom ends projecting below said interposer bottom surface
d. providing a module having a bottom surface with a plurality of electrical pads;
e. aligning the module, interposer aid printed circuit board wherein each aperture is positioned below one of the module pads and above one of the circuit board contacts;
f. providing a clamping means connected to said printed circuit board and said module;
g. clamping the interposer between the module and circuit board with the clamping means,
h. said clamping means forcing each of the circuit board contacts against said interposer lower surface about one of the apertures and each of the module pads against said interposer upper surface about one of the apertures;
i. each of the circuit board contacts and module pads thereby compressing one of the resilient conductors therebetween;
j. each of the compressed conductors exerting upward normal forces of at least 30 grams against each compressing pad, and downward normal forces of at least 30 grams against each compressing contact, and thereby electrically connecting the compressing pad and contact;
wherein said conductor may deform laterally responsive to lateral movement of said printed circuit board relative to said module and maintain the upward normal force of at least 30 grams and the downward normal force of at least 30 grams.

8 more elements

Dependencies are inferred from the claim text.