Solderless optical transceiver interconnect

• US 6,325,552 B1
• Filed: 02/14/2000
• Issued: 12/04/2001
• Est. Priority Date: 02/14/2000
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Brillhart, Mark Vodja
• Primary Examiner(s): NGO, HUNG NHAT
• Application Number:
  US09/503,876
• Time in Patent Office: 659 Days
• Field of Search: 385/88-94
• US Class Current: 385/88
• CPC Class Codes: G02B 6/4238 Soldering
• CPC Class Codes: G02B 6/4245 Mounting of the opto-electronic elements
• CPC Class Codes: G02B 6/4269 with heat sinks or radiation fins
• CPC Class Codes: G02B 6/4274 Electrical aspects G02B6/4263 and G02B6/4265 take precedence
• CPC Class Codes: G02B 6/428 containing printed circuit boards [PCB]
• CPC Class Codes: H05K 3/325 by abutting or pinching, i.e. without alloying process; mechanical auxiliary parts therefor adaptations of leads inserted in holes for press-fit connections H05K3/308
• CPC Class Codes: H05K 7/1061 co-operating by abutting

Abstract

A method and apparatus for assembly of a printed circuit board (PCB) having surface mount technology (SMT) components and an optics device utilizes a compressive connector to clamp the optics device to the printed circuit board and resist side loads. A metallized particle interconnect or equivalent array interfaces a land grid array on the optics device with a land grid array on the PCB. The connector passes through the PCB and through a hole in an integrated heat sink of the optics device. A pair of optics devices may thus be mounted to opposing sides of the PCB in tandem. Fiber optic cables may be attached to the optics devices so that they lead out of the optics devices parallel to the PCB.

Claims

1. A printed circuit board assembly, comprising:

a printed circuit board substrate;

a first land grid array of conductive pads disposed on a first side of said printed circuit board substrate;

a first metallized particle interconnect array having a plurality of conductive column conductors aligned so that said column conductors are in conductive contact with said conductive pads of said first land grid array;

a first optics device having an integrated heat sink element disposed on a first side thereof and a second land grid array of conductive pads disposed on a second side of said first optics device opposite said first side of said first optics device;

a first fiber optic connector disposed in said first optics device, said first fiber optic connector for receiving a fiber optic cable; and

at least one connector attaching said first optics device, said connector having an element passing through a hole in said integrated heat sink element of said first optics device and through said printed circuit board substrate to exert a compressive force urging said first optics device against said printed circuit board substrate.

2. An assembly in accordance with claim 1 wherein said fiber optic connector is arranged so that a fiber optic cable attached thereto will be disposed initially parallel to said printed circuit board substrate.

3. An assembly in accordance with claim 1, further comprising a surface mount component reflow soldered to a surface of said printed circuit board substrate.

4. An assembly in accordance with claim 2, further comprising a surface mount component reflow soldered to a surface of said printed circuit board substrate.

5. An assembly in accordance with claim 1 wherein said at least one connector comprises a nut and a bolt.

6. An assembly in accordance with claim 1 wherein said at least one connector comprises a rivet.

7. An assembly in accordance with claim 1, further comprising:

a third land grid array of conductive pads disposed on a second side of said printed circuit board substrate, said second side being opposite said first side;

a second metallized particle interconnect array having a plurality of conductive column connectors aligned so that said column conductors are in conductive contact with said conductive pads of said third land grid array;

a second optics device having an integrated heat sink element disposed on a first side thereof and a fourth land grid array of conductive pads disposed on a second side of said second optics device opposite said first side of said second optics device; and

a second fiber optic connector disposed in said first optics device, said second fiber optic connector for receiving a fiber optic cable;

wherein said at least one connector also passes through a hole in said integrated heat sink element of said second optics device and also exerts a compressive force urging said second optics device against said printed circuit board substrate.

8. An assembly in accordance with claim 7 wherein said fiber optic connectors are arranged so that fiber optic cables attached thereto will be disposed initially parallel to said printed circuit board substrate.

9. An assembly in accordance with claim 7, further comprising a surface mount component reflow soldered to a surface of said printed circuit board substrate.

10. An assembly in accordance with claim 8, further comprising a surface mount component reflow soldered to a surface of said printed circuit board substrate.

11. An assembly in accordance with claim 7 wherein said at least one connector comprises a nut and a bolt.

12. An assembly in accordance with claim 7 wherein said at least one connector comprises a rivet.

13. A method for fabricating a printed circuit board assembly having an optics device for receiving a fiber optic cable and at least one SMT component attached thereto, said method comprising:

preparing a printed circuit board substrate having a first land grid array of conductive pads disposed on a first side of said printed circuit board substrate and pads for SMT attachment of a SMT component;

reflow soldering said SMT component to said pads for SMT attachment;

removing excess solder flux from said printed circuit board substrate;

aligning a metallized particle interconnect array having a plurality of conductive column conductors so that said column conductors are in conductive contact with said conductive pads of said first land grid array;

disposing an optics device having an integrated heat sink element disposed on a first side thereof and a second land grid array of conductive pads disposed on a second side thereof opposite said first side, and a fiber optic connector for receiving a fiber optic cable, in alignment with said column conductors of said metallized particle interconnect; and

urging said optics device against said printed circuit board substrate with a connector passing through a hold in said integrated heat sink element and a hole in said printed circuit board substrate.

14. A method for fabricating a printed circuit board (PCB) assembly having a pair of opposed optics devices for receiving a corresponding pair of fiber optic cables and at least one SMT component attached to said assembly, said method comprising:

preparing a PCB substrate having a first and a second land grid array of conductive pads on opposite sides of said PCB substrate and pads for surface mount technology (SMT) attachment of a SMT component;

reflow soldering said SMT component to said pads for SMT attachment;

removing excess solder flux from said PCB substrate;

aligning a pair of metallized particle interconnect arrays each having a plurality of conductive column conductors so that said column conductors of each array are in conductive contact with said conductive pads of said respective first and second land grid arrays;

disposing first and second optics devices, each having an integrated heat sink element disposed on a first side thereof, a land grid array of conductive pads on a second side thereof opposite said first side, and a fiber optic connector for receiving a fiber optic cable, in alignment with said column conductors of said respective metallized particle interconnect arrays; and

urging said first and second optics devices against said PCB substrate with a connector passing through holes in said integrated heat sinks of said first and second optics devices and through said PCB substrate.