ESE
VITESSE
SEMICONDUCTOR CORPORATION
SEMICONDUCTOR CORPORATION
Preliminary Data Sheet
Gigabit Interconnect Chip
VSC7212
Package Thermal Considerations
The VSC7212 is packaged in a 100-pin, 14x14x1.0mm, cavity-down, thermally-enhanced TQFP. This
package uses an industry-standard EIAJ footprint but has been enhanced to improve thermal dissipation. The
construction of the package is shown in Figure 23.
Figure 23: TQFP Package Cross Section
Internal Heat Spreader
Plastic Molding Compound
Insulator
Lead
Table 17: Thermal Resistance
Die
Bond Wire
Symbol
θca
Description
TQFP
Units
oC/W
Thermal resistance from case to ambient in still air including conduction
through the leads.
39.9
oC/W
oC/W
oC/W
oC/W
θca-100
θca-200
θca-400
θca-600
Thermal resistance from case to ambient with 100 LFM airflow
Thermal resistance from case to ambient with 200 LFM airflow
Thermal resistance from case to ambient with 400 LFM airflow
Thermal resistance from case to ambient with 600 LFM airflow
37.1
35.3
33.5
31.7
o
The VSC7212 is designed to operate with a case temperature up to 100 C. The user must guarantee that the
case temperature specification is not violated. With the thermal resistances shown above, the 14mm thermally-
o
o
o
enhanced PQFP can operate in still air ambient temperatures of 52.1 C [52.1 C = 100 C - 1.0W * 39.9]. If the
ambient air temperature exceeds these limits then some form of cooling through a heatsink or an increase in
airflow must be provided.
Moisture Sensitivity Level
This device is rated at a Moisture Sensitivity Level 3 rating with maximum floor life of 168 hours at 30ºC,
60% relative humidity. Please refer to Application Note AN-20 for appropriate handling procedures.
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012
Tel: (800)-VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
Page 32
G52268-0, Rev 3.3
04/10/01
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
