mpc8560vt667jb Freescale Semiconductor, Inc, mpc8560vt667jb Datasheet - Page 88

• Manufacturer Part Number: mpc8560vt667jb
• Description: Mpc8560 Powerquicc Iii Integrated Communications Processor
• Manufacturer: Freescale Semiconductor, Inc

Thermal
16.2.4 Heat Sink Selection Examples
The following section provides a heat sink selection example using one of the commercially available heat
sinks.
16.2.4.1 Case 1
For preliminary heat sink sizing, the die-junction temperature can be expressed as follows:
where
During operation the die-junction temperatures (T
Table
and the air temperature rise within the electronic cabinet. An electronic cabinet inlet-air temperature (T
may range from 30° to 40°C. The air temperature rise within a cabinet (T
10°C. The thermal resistance of some thermal interface material (θ
T
following expression for T
The heat sink-to-ambient thermal resistance (θ
#2328B is shown in
Assuming an air velocity of 2 m/s, we have an effective θ
resulting in a die-junction temperature of approximately 71°C which is well within the maximum
operating temperature of the component.
88
I
of 30°C, a T
2. The temperature of air cooling the component greatly depends on the ambient inlet air temperature
Thermagon Inc.
4707 Detroit Ave.
Cleveland, OH 44102
Internet: www.thermagon.com
T
T
T
θ
θ
θ
P
JC
INT
SA
D
J
I
R
is the die-junction temperature
is the inlet cabinet ambient temperature
is the power dissipated by the device
is the air temperature rise within the computer cabinet
Die-junction temperature: T
is the junction-to-case thermal resistance
is the heat sink base-to-ambient thermal resistance
is the adhesive or interface material thermal resistance
T
T
R
J
J
of 5°C, a FC-PBGA package θ
= T
= 30°C + 5°C + (0.8°C/W +1.0°C/W + 3.3°C/W) × 7.0 W,
Figure
I
+ T
MPC8560 Integrated Processor Hardware Specifications, Rev. 4.2
R
J
+ (θ
55.
is obtained:
JC
+ θ
INT
J
= 30°C + 5°C + (0.8°C/W + 1.0°C/W + θ
+ θ
SA
SA
) × P
JC
) versus airflow velocity for a Thermalloy heat sink
J
= 0.8, and a power consumption (P
) should be maintained within the range specified in
D
SA+
888-246-9050
of about 3.3°C/W, thus
INT
) may be about 1°C/W. Assuming a
R
) may be in the range of 5° to
SA
Freescale Semiconductor
) × 7.0 W
D
) of 7.0 W, the
A
)