82546EB datasheet(39/47 Pages) INTEL

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Networking Silicon — 82546EB

Datasheet

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.

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.

Table 21. Thermal Characteristics

Symbol

Parameter

Value at specified airflow (m/s)

Units

qJA

Thermal resistance, junction-to-

ambient

17.7

15.6

14.8

14.0

C/Watt

qJC

Thermal resistance, junction-to-

case

6.8

C/Watt

82546EB Datasheet(PDF) 39 Page - Intel Corporation