MSC8122MPLOX Freescale Semiconductor / Motorola, MSC8122MPLOX Datasheet - Page 43

• Manufacturer Part Number: MSC8122MPLOX
• Description: 8122-LO SPEED-LEAD-BUFF.
• Manufacturer: Freescale Semiconductor / Motorola

3.5
An estimation of the chip-junction temperature
where
The power dissipation values for the MSC8122 are listed in Table 2-3. The ambient temperature for the device is the air
temperature in the immediate vicinity that would cool the device. The junction-to-ambient thermal resistances are JEDEC
standard values that provide a quick and easy estimation of thermal performance. There are two values in common usage: the
value determined on a single layer board and the value obtained on a board with two planes. The value that more closely
approximates a specific application depends on the power dissipated by other components on the printed circuit board (PCB).
The value obtained using a single layer board is appropriate for tightly packed PCB configurations. The value obtained using a
board with internal planes is more appropriate for boards with low power dissipation (less than 0.02 W/cm
convection) and well separated components. Based on an estimation of junction temperature using this technique, determine
whether a more detailed thermal analysis is required. Standard thermal management techniques can be used to maintain the
device thermal junction temperature below its maximum. If T
the power dissipation of the chip. You can verify the junction temperature by measuring the case temperature using a small
diameter thermocouple (40 gauge is recommended) or an infrared temperature sensor on a spot on the device case that is painted
black. The MSC8122 device case surface is too shiny (low emissivity) to yield an accurate infrared temperature measurement.
Use the following equation to determine T
where
Note:
4
Consult a Freescale Semiconductor sales office or authorized distributor to determine product availability and place an order.
Freescale Semiconductor
MSC8122
Part
T
R
P
P
P
T
θ
P
See MSC8102, MSC8122, and MSC8126 Thermal Management Design Guidelines (AN2601/D).
A
D
INT
I/O
JA
D
T
θ
Ordering Information
Flip Chip Plastic Ball Grid Array (FC-PBGA)
JA
= thermocouple (or infrared) temperature on top of the package (°C)
= ambient temperature near the package (°C)
= P
= power dissipation in the package (W)
= thermal characterization parameter (°C/W)
Thermal Considerations
= power dissipated from device on output pins (W)
= I
= junction-to-ambient thermal resistance (°C/W)
INT
DD
+ P
× V
Package Type
I/O
DD
= power dissipation in the package (W)
= internal power dissipation (W)
MSC8122 Quad Digital Signal Processor Data Sheet, Rev. 16
J
:
,
T
T
T
Voltage
J
J
J
Core
,
= T
1.1 V
1.2 V
in °C can be obtained from the following:
= T
A
T
+ (R
+ (θ
Temperature
θ
–40° to 105°C
–40° to 105°C
Operating
JA
J
JA
0° to 90°C
appears to be too high, either lower the ambient temperature or
× P
× P
D
D
)
)
Frequency
(MHz)
Core
300
400
400
500
MSC8122TVT4800V
MSC8122TVT6400V
MSC8122TVT6400
MSC8122VT8000
Lead-Free
Order Number
Ordering Information
2
with natural
MSC8122TMP4800V
MSC8122TMP6400V
MSC8122TMP6400
Lead-Bearing
MSC8122MP8000
Eqn. 1
Eqn. 2
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