Datasheet

MPC852T PowerQUICC™ Hardware Specifications, Rev. 4
Freescale Semiconductor 7
Thermal Characteristics
This device contains circuitry protecting against damage that high-static voltage or electrical fields cause;
however, Freescale recommends taking normal precautions to avoid application of any voltages higher
than maximum-rated voltages to this high-impedance circuit. Reliability of operation is enhanced if
unused inputs are tied to an appropriate logic voltage level (for example, either GND or V
DD
).
4 Thermal Characteristics
Table 3 shows the thermal characteristics for the MPC852T.
Table 2. Operating Temperatures
Rating Symbol Value Unit
Temperature
1
(standard)
1
Minimum temperatures are guaranteed as ambient temperature, T
A
. Maximum temperatures are guaranteed as junction
temperature, T
j
.
T
A(min)
0°C
T
j(max)
95 °C
Temperature (extended) T
A(min)
– 40 °C
T
j(max)
100 °C
Table 3. MPC852T Thermal Resistance Data
Rating Environment Symbol Value Unit
Junction-to-ambient
1
1
Junction temperature is a function of on-chip power dissipation, package thermal resistance, mounting site (board)
temperature, ambient temperature, airflow, power dissipation of other components on the board, and board thermal resistance.
Natural convection Single-layer board (1s) R
θJA
2
2
Per SEMI G38-87 and JEDEC JESD51-2 with the single-layer board horizontal
49 °C/W
Four-layer board (2s2p) R
θJMA
3
3
Per JEDEC JESD51-6 with the board horizontal
32
Airflow (200 ft/min) Single-layer board (1s) R
θJMA
3
41
Four-layer board (2s2p) R
θJMA
3
29
Junction-to-board
4
4
Thermal resistance between the die and the printed-circuit board per JEDEC JESD51-8. Board temperature is measured on
the top surface of the board near the package.
R
θJB
24
Junction-to-case
5
5
Indicates the average thermal resistance between the die and the case top surface as measured by the cold plate method
(MIL SPEC-883 Method 1012.1) with the cold plate temperature used for the case temperature. For exposed pad packages
where the pad would be expected to be soldered, junction-to-case thermal resistance is a simulated value from the junction to
the exposed pad without contact resistance.
R
θJC
13
Junction-to-package top
6
6
Thermal characterization parameter indicating the temperature difference between package top and the junction temperature
per JEDEC JESD51-2
Natural convection Ψ
JT
3
Airflow (200 ft/min) Ψ
JT
2