Revision 1.12 - Novenber 20, 2007
PPC405EX – PowerPC 405EX Embedded Processor
Preliminary Data Sheet
Thermal Management
Table 8. Package Thermal Specifications
The PPC405EX is designed to operate within a case temperature range TC defined in “Recommended DC Operating
Conditions” on page 48. Thermal resistance values for the EPBGA packages in a convection environment are as follows:
Airflow
ft/min (m/sec)
Parameter
Symbol
Unit
0 (0)
100 (0.51) 200 (1.02) 300 (1.52) 400 (2.02) 500 (2.53) 600 (3.03)
Junction-to-ambient
thermal resistance
without heat sink
Junction-to-ambient
thermal resistance
with heat sink
θJA
θJA
18.9
16.6
12.5
15.8
11.4
15.4
10.9
15.0
10.7
14.7
10.5
14.4
10.3
°C/W
°C/W
15.5
Resistance Value
Junction-to-case thermal
resistance
Junction-to-board thermal
resistance
θJC
θJB
8.96
°C/W
°C/W
13.74
Notes:
1. Values in the table are achieved with the following JEDEC standard board: 114.5mm x 101.6mm x 1.6mm, 4 layers.
2. For a chip mounted on a card with at least one signal and two power planes, the following relationships exist:
a. Case temperature, TC, is measured at top center of case surface with device soldered to circuit board.
b. TA = TC – PxθCA, where TA is ambient temperature and P is power consumption.
c. TCMax = TJMax – PxθJC, where TJMax is maximum junction temperature and P is power consumption.
The following heat sink was used in the above thermal analysis:
26.92mm x 27mm x 11.43mm
The heat sink is manufactured by:
Aavid Thermalloy, P/N 62925
AMCC Proprietary
47
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
