Parallel optical transceiver module having a heat dissipation system that dissipates heat and protects components of the module from particulates and handling
View Patent ↗A parallel optical transceiver module is provided that has a heat dissipation system that dissipates large amounts of heat, while also protecting the laser diodes, ICs and other components of the module from particulates, such as dust, for example, and from mechanical handling forces. The heat dissipation system is configured to be secured to the optical subassembly (OSA) of the module such that when the OSA is secured to the upper surface of the leadframe of the module, the OSA and the heat dissipation system cooperate to encapsulate at least the laser diodes and laser diode driver IC in a way that protects these components from dust and other particulates and from external mechanical forces. The heat dissipation system of the module is disposed for coupling with an external heat dissipation system, e.g., with a heat dissipation system that is provided by the customer.
1. A parallel optical transceiver module comprising:
an electrical subassembly (ESA) comprising a circuit board, a leadframe secured to the circuit board, at least one integrated circuit (IC) mounted on an upper surface of the leadframe, and a plurality of active optical devices mounted on the upper surface of the leadframe, the ESA having one or more alignment and interlocking features thereon;
an optical subassembly (OSA) mechanically coupled with the ESA, the OSA having a plurality of optical elements for directing optical signals between ends of a plurality of optical fibers and the active optical devices mounted on the upper surface of the leadframe, the OSA having one or more alignment and interlocking features configured to be aligned and interlocked with the alignment and interlocking features of the ESA to enable the OSA and the ESA to be mechanically coupled with one another; and
a heat dissipation system mechanical coupled to the OSA, the heat dissipation system comprising a material of high thermal conductivity, the heat dissipation system comprising at least first and second heat blocks, the first and second heat blocks having respective mating features that mate with respective mating features of the OSA to mechanically couple the first and second heat blocks to first and second sides, respectively, of the OSA, wherein the first and second heat blocks have lower surfaces that are thermally coupled with the upper surface of the leadframe of the ESA, and wherein the first and second heat blocks have upper surfaces that are disposed above an upper surface of the OSA and are open and uncovered to enable the upper surfaces of the heat blocks to be thermally coupled with a heat dissipation system that is external to the parallel optical transceiver module to enable heat that is transferred from the leadframe into the heat dissipation system of the parallel optical transceiver module to be transferred into the external heat dissipation system, and wherein the mechanical coupling together of the ESA and the OSA and the mechanical coupling together of the heat dissipation system and the OSA provide an encapsulation for said plurality of active optical devices and said at least one IC that protects said plurality of active optical devices and said at least one IC from particulates and mechanical handling forces.
2. The parallel optical transceiver module of claim 1 , wherein said plurality of active optical devices correspond to a plurality of laser diodes, and wherein said at least one IC includes a plurality of laser diode driver ICs for driving respective ones of the laser diodes.
3. The parallel optical transceiver module of claim 1 , wherein said plurality of active optical devices correspond to a plurality of photodiodes, and wherein said at least one IC includes a receiver IC.
4. The parallel optical transceiver module of claim 1 , wherein said plurality of active optical devices include a plurality of laser diodes and a plurality of photodiodes, and wherein said at least one IC includes at least one laser diode driver IC for driving the laser diodes and at least one receiver IC for receiving and processing electrical signals produced by the photodiodes.
5. The parallel optical transceiver module of claim 1 , wherein the lower surfaces of the first and second heat blocks are thermally coupled with the upper surface of the leadframe of the ESA by a thermally conductive epoxy.
6. The parallel optical transceiver module of claim 1 , wherein the respective mating features of the OSA that mate with the respective mating features of the first and second heat blocks are disposed on the first and second sides of the OSA, and wherein the first and second sides of the OSA to which the first and second heat blocks are coupled are opposite one another such that the first and second heat blocks are opposite one another when coupled to the OSA.
7. The parallel optical transceiver module of claim 1 , wherein the first and second heat blocks comprise copper.
8. The parallel optical transceiver module of claim 1 , wherein the first and second heat blocks comprise aluminum.
9. The parallel optical transceiver module of claim 1 , wherein the respective mating features of the OSA are first and second portions of plastic that are formed during a molding process that is used to mold a housing of the OSA.
10. The parallel optical transceiver module of claim 9 , wherein the first and second heat blocks having first and second openings, respectively, formed therein, and wherein the first and second portions of the plastic are portions of plastic that flow into the first and second openings during the molding process and subsequently harden when the plastic cools.
11. A method for dissipating heat in a parallel optical transceiver module, the method comprising:
providing an electrical subassembly (ESA) comprising a circuit board, a leadframe secured to the circuit board, at least one integrated circuit (IC) mounted on an upper surface of the leadframe, and a plurality of active optical devices mounted on the upper surface of the leadframe;
providing an optical subassembly (OSA) having a plurality of optical elements for directing optical signals between ends of a plurality of optical fibers and the active optical devices mounted on the upper surface of the leadframe;
providing a heat dissipation system comprising a thermally conductive material, the heat dissipation system being configured to be mechanically coupled to the OSA;
mechanically coupling the heat dissipation system to the OSA; and
mechanically coupling the OSA to the ESA, wherein the heat dissipation system comprises at least first and second heat blocks, the first and second heat blocks having respective mating features that mate with respective mating features of the OSA to mechanically couple the first and second heat blocks to first and second sides, respectively, of the OSA, wherein the first and second heat blocks have lower surfaces that are thermally coupled with the upper surface of the leadframe of the ESA, and wherein the first and second heat blocks have upper surfaces that are disposed above an upper surface of the OSA and are open and uncovered to enable the upper surfaces to be thermally coupled with a heat dissipation system that is external to the parallel optical transceiver module to enable heat that is transferred from the leadframe into the heat dissipation system of the parallel optical transceiver module to be transferred into the external heat dissipation system, and wherein the mechanical coupling together of the ESA and the OSA and the mechanical coupling together of the heat dissipation system and the OSA provide an encapsulation for said plurality of active optical devices and said at least one IC that protects said plurality of active optical devices and said at least one IC from particulates and mechanical handling forces.
12. The method of claim 11 , further comprising:
thermally coupling the heat dissipation system of the parallel optical transceiver module to an external heat dissipation system to enable heat to be transferred into the external heat dissipation system from the heat dissipation system of the parallel optical transceiver module.
13. The method of claim 11 , wherein said plurality of active optical devices correspond to a plurality of laser diodes, and wherein said at least one IC includes a plurality of laser diode driver ICs for driving respective ones of the laser diodes.
14. The method of claim 11 , wherein said plurality of active optical devices correspond to a plurality of photodiodes, and wherein said at least one IC includes a receiver IC.
15. The method of claim 11 , wherein said plurality of active optical devices include a plurality of laser diodes and a plurality of photodiodes, and wherein said at least one IC includes at least one laser diode driver IC for driving the laser diodes and at least one receiver IC for receiving and processing electrical signals produced by the photodiodes.
16. The method of claim 11 , wherein the lower surfaces of the first and second heat blocks are thermally coupled with the upper surface of the leadframe of the ESA by a thermally conductive epoxy.
17. The method of claim 11 , wherein the respective mating features of the OSA that mate with the respective mating features of the first and second heat blocks are disposed on the first and second sides of the OSA, and wherein the first and second sides of the OSA to which the first and second heat blocks are coupled are opposite one another such that the first and second heat blocks are opposite one another when coupled to the OSA.
18. The method of claim 11 , wherein the first and second heat blocks comprise copper.
19. The method of claim 11 , wherein the first and second heat blocks comprise aluminum.
20. The method of claim 11 , wherein the respective mating features of the OSA are first and second portions of plastic that are formed during a molding process that is used to mold a housing of the OSA.
21. The method of claim 20 , wherein the first and second heat blocks have first and second openings, respectively, formed therein, and wherein the first and second portions of the plastic are portions of plastic that flow into the first and second openings during the molding process and subsequently harden when the plastic cools.