mpc8544e Freescale Semiconductor, Inc, mpc8544e Datasheet - Page 97

• Manufacturer Part Number: mpc8544e
• Description: Mpc8544e Powerquicc Iii Integrated Processor
• Manufacturer: Freescale Semiconductor, Inc

Table 71
Simulations with heat sinks were done with the package mounted on the 2s2p thermal test board. The
thermal interface material was a typical thermal grease such as Dow Corning 340 or Wakefield 120 grease.
For system thermal modeling, the MPC8544E thermal model without a lid is shown in
substrate is modeled as a block 29 × 29 × 1.18 mm with an in-plane conductivity of 18.0 W/m•K and a
through-plane conductivity of 1.0 W/m•K. The solder balls and air are modeled as a single block
29 × 29 × 0.58 mm with an in-plane conductivity of 0.034 W/m•K and a through plane conductivity of
12.1 W/m•K. The die is modeled as 7.6 × 8.4 mm with a thickness of 0.75 mm. The bump/underfill layer
is modeled as a collapsed thermal resistance between the die and substrate assuming a conductivity of
6.5 W/m•K in the thickness dimension of 0.07 mm. The die is centered on the substrate. The thermal model
uses approximate dimensions to reduce grid. Please refer to
20.2
Table 72
Freescale Semiconductor
Wakefield 53 × 53 × 25 mm pin fin
Wakefield 53 × 53 × 25 mm pin fin
Aavid 35 × 31 × 23 mm pin fin
Aavid 35 × 31 × 23 mm pin fin
Aavid 30 × 30 × 9.4 mm pin fin
Aavid 30 × 30 × 9.4 mm pin fin
Aavid 43 × 41 × 16.5 mm pin fin
Aavid 43 × 41 × 16.5 mm pin fin
Conductivity
provides the thermal resistance with heat sink in open flow.
shows the MPC8544E thermal model.
Recommended Thermal Model
Heat Sink with Thermal Grease
Silicon
Kz
Kx
Ky
Kz
MPC8544E PowerQUICC III Integrated Processor Hardware Specifications, Rev. 4
Bump/Underfill (7.6 × 8.4 × 0.070 mm) Collapsed Thermal Resistance
Table 71. Thermal Resistance with Heat Sink in Open Flow
Preliminary—Subject to Change Without Notice
Table 72. MPC8544EThermal Model
Freescale Confidential Proprietary
Substrate (29 × 29 × 1.18 mm)
Temperature dependent
Die (7.6 × 8.4 × 0.75mm)
Value
6.5
1.0
18
18
Natural convection
Natural convection
Natural convection
Natural convection
Air Flow
1 m/s
1 m/s
1 m/s
1 m/s
Figure 59
for actual dimensions.
Thermal Resistance (°C/W)
W/m•K
W/m•K
Units
Figure
—
11.6
6.1
3.0
8.1
4.3
6.7
8.3
4.3
60. The
Thermal
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