MC9S08PT60 Datasheet, PDF (17/37 Pages) Freescale Semiconductor, Inc – MC9S08PT60

Thermal specifications
5.3 Thermal specifications
5.3.1 Thermal characteristics
This section provides information about operating temperature range, power dissipation,
and package thermal resistance. Power dissipation on I/O pins is usually small compared
to the power dissipation in on-chip logic and voltage regulator circuits, and it is user-
determined rather than being controlled by the MCU design. To take P_I/O into account in
power calculations, determine the difference between actual pin voltage and V_SS or V_DD
and multiply by the pin current for each I/O pin. Except in cases of unusually high pin
current (heavy loads), the difference between pin voltage and V_SS or V_DD will be very
small.
Table 8. Thermal characteristics
Rating
Operating temperature range
(packaged)
Junction temperature range
64-pin LQFP
64-pin QFP
48-pin LQFP
44-pin LQFP
32-pin LQFP
64-pin LQFP
64-pin QFP
48-pin LQFP
44-pin LQFP
32-pin LQFP
Symbol
T_A
Value
-40 to 105
T_J
-40 to 150
Thermal resistance single-layer board
θ_JA
71
θ_JA
61
θ_JA
81
θ_JA
75
θ_JA
86
Thermal resistance four-layer board
θ_JA
53
θ_JA
47
θ_JA
57
θ_JA
53
θ_JA
57
Unit
°C
°C
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
°C/W
The average chip-junction temperature (T_J) in °C can be obtained from:
T_J = T_A + (P_D × θ_JA)
Where:
T_A = Ambient temperature, °C
MC9S08PT60 Series Data Sheet, Rev. 3, 4/2012.
Freescale Semiconductor, Inc.
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