VITESSE
SEMICONDUCTOR CORPORATION
Advance Product Information
Quad Transceiver
for Gigabit Ethernet
VSC7186
Package Thermal Characteristics
The VSC7186 is packaged in a 23 mm BGA package with 1.27mm eutectic ball spacing. The construction
of the package is shown below.
Figure 6: Package Cross Section
Copper Heat Spreader
Die
Wirebond
Die Attach Epoxy
Encapsulant
Adhesive
Polyimide Dielectric
Eutectic Solder Balls
o
The VSC7186 is designed to operate with a case temperature up to 100 C. In order to comply with this tar-
o
get, the user must guarantee that the case temperature specification of 100 C is not violated. With the Thermal
o
o
o
Resistances shown below, the VSC7186 can operate in still air ambient temperatures of 40 C [ 40 C = 100 C
o
- 2.5W * 24 C/W ]. If the ambient air temperature exceeds these limits then some form of cooling through a
heatsink or an increase in airflow must be provided.
Table 7: Thermal Resistance
Symbol
θjc
Description
Value
Units
Thermal resistance from junction to case
4.3
oC/W
Thermal resistance from case to ambient in still air including
conduction through the leads.
θca
24
oC/W
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 with200 LFM airflow
Thermal resistance from case to ambient with 400 LFM airflow
Thermal resistance from case to ambient with 600 LFM airflow
21
18.5
17
15
Moisture Sensitivity Level
This device is rated at with a Moisture Sensitivity Level 3 rating. Refer to Application Note AN-20 for
appropriate handling procedures.
Page 14
VITESSE SEMICONDUCTOR CORPORATION
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: 805/987-5896
G52306-0, Rev. 2.0
3/27/00
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
