Ordering Information
MSC8113 Tri-Core Digital Signal Processor Data Sheet, Rev. 1
Freescale Semiconductor
41
3.5
Thermal Considerations
An estimation of the chip-junction temperature, TJ, in °C can be obtained from the following:
TJ = TA + (R
θJA × PD)
Eqn. 1
where
TA = ambient temperature near the package (°C)
R
θJA = junction-to-ambient thermal resistance (°C/W)
PD = PINT + PI/O = power dissipation in the package (W)
PINT = IDD × VDD = internal power dissipation (W)
PI/O = power dissipated from device on output pins (W)
The power dissipation values for the MSC8113 are listed in Table 4. 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
2 with natural
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 TJ appears to be too high, either lower the ambient temperature or
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 MSC8113 device case surface is too shiny (low emissivity) to yield an accurate infrared temperature measurement.
Use the following equation to determine TJ:
TJ = TT + (θJA × PD)
Eqn. 2
where
TT = thermocouple (or infrared) temperature on top of the package (°C)
θ
JA = thermal characterization parameter (°C/W)
PD = power dissipation in the package (W)
Note:
See MSC8102, MSC8122, and MSC8126 Thermal Management Design Guidelines (AN2601/D).
4
Ordering Information
Consult a Freescale Semiconductor sales office or authorized distributor to determine product availability and place an order.
Part
Package Type
Core
Voltage
Operating
Temperature
Core
Frequency
(MHz)
Order Number
Lead-Free
Lead-Bearing
MSC8113
Flip Chip Plastic Ball Grid Array (FC-PBGA)
1.1 V
–40° to 105°C
300
MSC8113TVT3600V
MSC8113TMP3600V
400
MSC8113TVT4800V
MSC8113TMP4800V