VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
Quad Port Bypass Circuit for 1.0625 Gbit/sec
Fibre Channel Arbitrated Loop Disk Arrays
Package Thermal Characteristics
The VSC7122 is packaged into a standard plastic quad flatpack with an embedded, but unexposed thermal
slug. This package adheres to industry standard EIAJ footprints for a 10x10mm body, 44 lead PQFP. The pack-
age construction is as shown in Figure 6. The 44 PQFP with embedded slug has the thermal properties shown in
Table 5. This package allows the VSC7122 to operate with ambient temperatures up to 70oC in still air.
Figure 6: Package Cross Reference
Die
Plastic Molding Compound
Wire Bond
Lead
Insulator
Table 5: 44 PQFP Thermal Resistance
Symbol
Description
Value
Units
o
θ
Thermal resistance from case to ambient, still air
50
43
39
36
34
C/W
ca-0
o
θ
Thermal resistance from case to ambient, 100 LFPM air
Thermal resistance from case to ambient, 200 LFPM air
Thermal resistance from case to ambient, 400 LFPM air
Thermal resistance from case to ambient, 600 LFPM air
C/W
ca-100
ca-200
ca-400
ca-600
o
θ
θ
θ
C/W
o
C/W
o
C/W
Moisture Sensitivity Level
This device is rated with a moisture sensitivity level 3 rating. Refer to Application Note AN-20 for appro-
priate handling procedures.
Page 10
VITESSE SEMICONDUCTOR CORPORATION
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: 805/987-5896
G52155-0, Rev. 2.1
8/31/98
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
