© VITESSE SEMICONDUCTOR CORPORATION

Page 17

8/28/00

741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: 805/987-5896

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7146

2.5Gb/s, 20-Bit Transceiver

G52162-0, Rev. 2.7

Package Thermal Characteristics

The VSC7146 is packaged in an 80-pin, 14mm thermally-enhanced EDQUAD with an internal heat

spreader. These packages use industry-standard EIAJ footprints, which have been enhanced to improve thermal

dissipation. The construction of the packages are as shown in Figure 11. The VSC7146 is designed to operate

Figure 11: Package Cross Section

Table 7: Thermal Resistance

Symbol

Description

Value

Units

θ

jc

Thermal resistance from junction-to-case

2.5

θ

ca-0

Thermal resistance from case-to-ambient, still air

35

θ

ca-100

Thermal resistance from case-to-ambient, 100 LFPM air

29

θ

ca-200

Thermal resistance from case-to-ambient, 200 LFPM air

26

θ

ca-400

Thermal resistance from case-to-ambient, 400 LFPM air

22

θ

ca-600

Thermal resistance from case-to-ambient, 600 LFPM air

19

Lead

Die

Plastic Molding Compound

Insulator

Wire Bond

Exposed Heat Slug

Thermal Epoxy