MPC755CRX400LE Freescale Semiconductor, MPC755CRX400LE Datasheet - Page 48

• Manufacturer Part Number: MPC755CRX400LE
• Description: IC MPU 32BIT 400MHZ PPC 360-CBGA
• Manufacturer: Freescale Semiconductor

Specifications of MPC755CRX400LE

• Processor Type: MPC7xx PowerPC 32-Bit
• Speed: 400MHz
• Voltage: 2V
• Mounting Type: Surface Mount
• Package / Case: 360-FCCBGA
• Family Name: MPC7xx
• Device Core: PowerPC
• Device Core Size: 64b
• Frequency (max): 400MHz
• Instruction Set Architecture: RISC
• Supply Voltage 1 (typ): 2V
• Operating Supply Voltage (max): 2.1V
• Operating Supply Voltage (min): 1.9V
• Operating Temp Range: 0C to 105C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 360
• Package Type: FCCBGA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Features: -
• Lead Free Status / Rohs Status: Not Compliant

System Design Information
8.8.3
This section provides a heat sink selection example using one of the commercially-available heat sinks.
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 the thermal interface material (θ
a T
following expression for T
Die-junction temperature: T
For a Thermalloy heat sink #2328B, the heat sink-to-ambient thermal resistance (θ
velocity is shown in
Assuming an air velocity of 0.5 m/s, we have an effective R
resulting in a die-junction temperature of approximately 76°C which is well within the maximum
operating temperature of the component.
Other heat sinks offered by Aavid Thermalloy, Alpha Novatech, The Bergquist Company, IERC, Chip
Coolers, and Wakefield Engineering offer different heat sink-to-ambient thermal resistances, and may or
may not need airflow.
48
a
of 30°C, a T
3. The temperature of air cooling the component greatly depends on the ambient inlet air temperature
Shin-Etsu MicroSi, Inc.
10028 S. 51st St.
Phoenix, AZ 85044
Internet: www.microsi.com
Thermagon Inc.
4707 Detroit Ave.
Cleveland, OH 44102
Internet: www.thermagon.com
T
T
T
θ
θ
θ
P
jc
int
sa
a
r
d
j
is the die-junction temperature
is the air temperature rise within the computer cabinet
is the inlet cabinet ambient temperature
is the power dissipated by the device
is the junction-to-case thermal resistance
is the heat sink base-to-ambient thermal resistance
is the adhesive or interface material thermal resistance
Heat Sink Selection Example
T
T
j
j
= T
r
= 30°C + 5°C + (0.1°C/W + 1.0°C/W + 7°C/W) × 5.0 W,
of 5°C, a CBGA package R
a
Figure
+ T
MPC755 RISC Microprocessor Hardware Specifications, Rev. 8
r
+ (θ
j
28.
is obtained:
j
jc
= 30°C + 5°C + (0.1°C/W + 1.0°C/W + θ
+ θ
int
+ θ
sa
) × P
θjc
d
< 0.1, and a power consumption (P
j
) should be maintained less than the value specified in
sa
888-642-7674
888-246-9050
of 7°C/W, thus
int
) is typically about 1°C/W. Assuming
sa
r
) may be in the range of 5° to
) × 5.0 W
sa
d
Freescale Semiconductor
) versus airflow
) of 5.0 W, the
a
)