VSC8117QP2 VITESSE [Vitesse Semiconductor Corporation], VSC8117QP2 Datasheet - Page 18

• Manufacturer Part Number: VSC8117QP2
• Description: ATM/SONET/SDH 622/155 Mb/s Transceiver Mux/Demux with Integrated Clock Generation and Clock Recovery
• Manufacturer: VITESSE [Vitesse Semiconductor Corporation]

ATM/SONET/SDH 622/155 Mb/s Transceiver Mux/Demux
with Integrated Clock Generation and Clock Recovery
Page 18
Package Thermal Characteristics
to the industry-standard EIAJ footprint for a 10x10mm body but has been enhanced to improve thermal dissipa-
tion with the inclusion of an exposed Copper Heat Spreader. The package construction is as shown in Figure 10.
the die to the exposed surface of the heat spreader and from the die to the lead frame through the heat spreader
overlap of the lead frame.
Table 16: 64-Pin PQFP Thermal Resistance
The VSC8117QB1 is designed to operate at a maximum case temperature of up to 115
antee that the maximum case temperature specification is not violated. Given the thermal resistance of the pack-
age in still air, the user can operate the VSC8117QB1 in still air if the ambient temperature does not exceed
55
priate heatsink must be used with the part or adequate airflow must be provided.
o
C (55
The VSC8117 is packaged into a thermally-enhanced plastic quad flatpack (PQFP). This package adheres
The thermal resistance for the VSC8117 package is improved through low thermal resistance paths from
Symbol
ca-100
ca-200
ca-400
ca-600
ca
jc
o
C = 115
Insulator
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: [phone]
Thermal resistance from junction to case
Thermal resistance from case to ambient in still air including conduction through
the leads for a non-thermally saturated board.
Thermal resistance from case to ambient in 100 LPFM air
Thermal resistance from case to ambient in 200 LPFM air
Thermal resistance from case to ambient in 400 LPFM air
Thermal resistance from case to ambient in 600 LPFM air
o
C - 1.6W * 37
Wire Bond
Copper Heat Spreader
o
VITESSE
C/W). If operation above this ambient temperature is required, then an appro-
VITESSE SEMICONDUCTOR CORPORATION
SEMICONDUCTOR CORPORATION
Figure 11: Package Cross Section
Description
Die
Plastic Molding Compound
o
C. The user must guar-
Lead
Value
2.5
37
31
28
24
22
VSC8117
Data Sheet
G52221-0, Rev 4.1
Units
o
o
o
o
o
o
C/W
C/W
C/W
C/W
C/W
C/W
1/8/00