82598EB Datasheet, PDF (583/596 Pages) Intel Corporation – Intel® 82598EB 10 Gigabit Ethernet Controller Datasheet

Intel^® 82598EB 10 GbE Controller - Thermal Specifications
Junction: Refers to a P-N junction on the silicon. In this document, it is used as a temperature
reference point (for example, _JA refers to the junction to ambient thermal resistance).
Ambient: Refers to local ambient temperature of the bulk air approaching the component. It can be
measured by placing a thermocouple approximately one inch upstream from the component edge.
Lands: Pads on the PCB to which BGA balls are soldered.
PCB: Printed circuit board.
Printed Circuit Assembly (PCA): An assembled PCB.
Thermal Design Power (TDP): Estimated maximum possible/expected power generated in a
component by a realistic application.
LFM: Linear feet per minute (airflow).
JA ^{(Theta JA): Thermal resistance junction-to-ambient, °C/W.}
JT ^{(Psi JT): Junction-to-top (of package) thermal characterization parameter, °C/W.}
8.16.3 Thermal Specifications
To ensure proper operation, the thermal solution must maintain a case temperature at or below the
values specified in Table 8-8. System-level or component-level thermal enhancements are required to
dissipate the generated heat to ensure the case temperature never exceeds the maximum
temperatures. Table 8-9 lists the thermal performance parameters for the JEDEC JESD51-2 standard.
Analysis indicates that real applications are unlikely to cause the 82598 to be at Tcase-max for
sustained periods of time. Given that Tcase should reasonably be expected to be a distribution of
temperatures, sustained operation at Tcase-max may affect long-term reliability of the system, and
sustained performance at Tcase-max should be evaluated during the thermal design process and steps
taken to reduce the Tcase temperature.
Good system airflow is critical to dissipate the highest possible thermal power. The size and number of
fans, etc. and their placement in relation to components and airflow channels within the system
determine airflow.
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