VITESSE

SEMICONDUCTOR CORPORATION

Data Sheet

VSC8113

ATM/SONET/SDH 622 Mb/s Transceiver Mux/Demux

with Integrated Clock Generation and Clock Recovery

Page 22

© VITESSE SEMICONDUCTOR CORPORATION

G52154-0, Rev 4.2

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

3/19/99

The VSC8113 is manufactured in a 100PQFP package which is supplied by two different vendors. The crit-

ical dimensions in the drawing represent the superset of dimensions for both packages. The significant differ-

ence between the two packages is in the shape and size of the heatspreader which needs to be considered when

attaching a heatsink.

Package Thermal Characteristics

The VSC8113 is packaged in a thermally enhanced 100PQFP with an embedded heat sink. The heat sink

surface configurations are shown in the package drawings. With natural convection, the case to air thermal resis-

Table 18: Theta Case to Ambient versus Air Velocity

Air Velocity

(LFPM)

Case to air thermal resistance

027.5

100

23.1

200

19.8

400

17.6

600

16