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MC9S08DZ60MLC Datasheet, PDF (371/416 Pages) Freescale Semiconductor, Inc – MC9S08DZ60 Series Features | |||
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Appendix A Electrical Characteristics
Table A-3. Thermal Characteristics
Num C
Rating
Symbol
Value
Unit
Temp.
Code
1
D
Operating temperature range (packaged)
â40 to 125
M
TA
â40 to 105
°C
V
â40 to 85
C
2
T Maximum Junction Temperature1
TJ
135
°C
â
3
D Thermal resistance2
Single-layer board
64-pin LQFP
θJA
69
°C/W
48-pin LQFP
θJA
75
°C/W
32-pin LQFP
θJA
80
°C/W
Four-Layer board
64-pin LQFP
θJA
51
°C/W
48-pin LQFP
θJA
51
°C/W
32-pin LQFP
θJA
52
°C/W
1 Junction temperature is a function of die size, on-chip power dissipation, package thermal resistance, mounting site
(board) temperature, ambient temperature, air ï¬ow, power dissipation of other components on the board, and board
thermal resistance.
2 Junction to Ambient Natural Convection
The average chip-junction temperature (TJ) in °C can be obtained from:
TJ = TA + (PD à θJA)
Eqn. A-1
where:
TA = Ambient temperature, °C
θJA = Package thermal resistance, junction-to-ambient, °C/W
PD = Pint + PI/O
Pint = IDD Ã VDD, Watts â chip internal power
PI/O = Power dissipation on input and output pins â user determined
For most applications, PI/O << Pint and can be neglected. An approximate relationship between PD and TJ
(if PI/O is neglected) is:
PD = K ÷ (TJ + 273°C)
Solving equations 1 and 2 for K gives:
Eqn. A-2
K = PD à (TA + 273°C) + θJA à (PD)2
Eqn. A-3
MC9S08DZ60 Series Data Sheet, Rev. 4
Freescale Semiconductor
371
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