VITESSE
SEMICONDUCTOR CORPORATION
Data Sheet
High Performance Serial
Backplane Transceiver
VSC870
Package Thermal Characteristics
The VSC870 is packaged in a thermally-enhanced 21mm 192TBGA with an embedded heat sink. The heat sink
surface configurations are shown in the package drawings. With natural convection, the junction-to-case thermal
resistance is estimated to be 1.49oC/W. The approximate air flow versus thermal resistance relationship is shown in
Table 8. Refer to the application note AN-36 for thermal management and selection of heat sinks.
Table 8: Theta Junction-to-Ambient versus Air Velocity
Junction-to-Ambient Thermal Resistance (oC/W)
Air Velocity (LFPM)
Low Conductivity
Two Layer Board
High Conductivity
Four Layer Board
0
35.0
30.0
26.0
22.0
20.0
25.0
22.0
20.0
17.5
16.5
100
200
400
600
Ordering Information
The order number for this product is formed by a combination of the device number and package type.
xx
VSC870
Device Type
Package
TX: 192 BGA
High Performance Serial
Backplane Transceiver
Extended Commerical Temperature: 0°C ambient to +85°C case
Notice
Vitesse Semiconductor Corporation (“Vitesse”) provides this document for informational purposes only. All information in this document, includ-
ing descriptions of features, functions, performance, technical specifications and availability, is subject to change without notice at any time. Noth-
ing contained in this document shall be construed as extending any warranty or promise, express or implied, that any Vitesse product will be
available as described or will be suitable for or will accomplish any particular task.
Vitesse products are not intended for use in life support appliances, devices or systems. Use of a Vitesse product in such applications without writ-
ten consent is prohibited.
© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012
Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com
Internet: www.vitesse.com
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VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
