MC9S08QE16CLC Datasheet, PDF (307/350 Pages) Freescale Semiconductor, Inc – Low-power wireless applications, Gas, water and heater meters

Appendix A Electrical Characteristics and Timing Specifications
A.4 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 it is user-determined rather than being controlled by the MCU design. In order 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 A-3. Thermal Characteristics
Rating
Operating temperature range (packaged)
Thermal resistance ^1,2,3,4
Symbol
T_A
Value
T_L to T_H
–40 to 125
Unit
C
64-pin QFP
64-pin LQFP
48-pin QFN
44-pin LQFP
1s
2s2p
1s
2s2p
1s
2s2p
_JA
1s
2s2p
57
43
69
54
84
27
C/W
73
56
32-pin LQFP
1s
85
2s2p
56
1 _{Junction temperature is a function of die size, on-chip power dissipation, package thermal}
resistance, mounting site (board) temperature, ambient temperature, air flow, power dissipation
of other components on the board, and board thermal resistance.
2 _{Junction to Ambient Natural Convection}
3 _{1s - Single Layer Board, one signal layer}
4 _{2s2p - Four Layer Board, 2 signal and 2 power layers}
MC9S08AC60 Series Data Sheet, Rev. 3
Freescale Semiconductor
307