82546EB Datasheet, PDF (39/47 Pages) Intel Corporation – Dual Port Gigabit Ethernet Controller

Networking Silicon — 82546EB
5.3
Thermal Specifications
The 82546EB device is specified for operation when the ambient temperature (TA) is within the
range of 0 C to 55 C. The maximum permitted junction temperature is 120 C.
TC (case temperature) is calculated using the equation:
TC = TA + P (qJA - q JC)
TJ (junction temperature) is calculated using the equation:
TJ = TA + P qJA
The power consumption (P) is calculated by using the typical ICC and nominal VCC. The thermal
resistances are shown in Table 21.
Table 21. Thermal Characteristics
Symbol
Parameter
qJA
Thermal resistance, junction-to-
ambient
qJC
Thermal resistance, junction-to-
case
Value at specified airflow (m/s)
0
1
2
3
17.7
15.6
14.8
14.0
Units
C/Watt
6.8
6.8
6.8
6.8
C/Watt
Thermal resistances are determined empirically with test devices mounted on standard thermal test
boards. Real system designs may have different characteristics due to board thickness, arrangement
of ground planes, and proximity of other components. The case temperature measurements should
be used to assure that the 82546EB device is operating under recommended conditions.
Datasheet
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