This is the mechanical and thermal interface for plugging four QSFP+ or QSFP28 transceiver modules into a line card or switch backplane. The press-fit termination means it installs without solder: the compliant pins cold-form into the plated through-hole, which is standard for backplane assemblies where rework access is limited and solder-joint reliability under thermal cycling is critical. The EMI shielding is built into the cage structure to contain the radiated emissions from the high-speed differential pairs running at 25 or 28 Gbps per lane.
Press-Fit Assembly and Board Layout
The press-fit tail drives the board-side process: the cage is pressed into the PCB using a pneumatic or arbor press with a back-up tool supporting the opposite side. No wave solder or reflow step is needed on the cage itself, though the host board may still run through reflow for other components. The heat sink is integral to the cage; it draws thermal energy from the module's top surface through a thermal interface pad (not included). Airflow direction over the fins should be considered in the chassis thermal design.