VITESSE
SEMICONDUCTOR CORPORATION
Preliminary Datasheet
500 Mb/s Video
Shift Register IC
VSC6424
Package Thermal Considerations
Figure 10: ΘCA vs Air Velocity for the 128 PQFP (14mmx20mmx2.7mm)
30
Air Vel.
LFPM
Theta(ca)
oC/W
25
20
0
27.5
23.1
19.8
17.6
16.0
100
200
400
600
15
10
5
0
200
Air Velocity (LFPM)
CA measurement method: Semi-standard G38-87, in a wind tunnel
Semi-standard G42-88/JEDEC JC 15.1 #1 FR4 PCB 3”x4.5”x0.62”
400
600
0
Θ
Notice
This document contains preliminary information about a new product in the preproduction phase of devel-
opment. The information in this document is based on initial product characterization. Vitesse reserves the right
to alter specifications, features, capabilities, functions, manufacturing release dates, and even general availabil-
ity of the product at any time. The reader is cautioned to confirm this datasheet is current prior to using it for
design.
Warning
Vitesse Semiconductor Corporation’s product are not intended for use in life support appliances, devices or
systems. Use of a Vitesse product in such applications without the written consent is prohibited.
Page 18
VITESSE SEMICONDUCTOR CORPORATION
G52236-0, Rev 3.0
741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: 805/987-5896
7/13/99
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
