Datasheet

Appendix A Electrical Characteristics
MC9S08SH32 Series Data Sheet, Rev. 2
Freescale Semiconductor 289
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 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 A-3. Thermal Characteristics
Num C Rating Symbol Value Unit
1 — Operating temperature range (packaged)
Temperature Code M T
A
–40 to 125 °C
Temperature Code C –40 to 85
2 D Maximum junction temperature T
J
135 °C
3 D Thermal resistance, Single-layer board
16-pin TSSOP θ
JA
108 °C/W
20-pin TSSOP 94
28-pin SOIC 57
28-pin TSSOP 72
4 D Thermal resistance, Four-layer board
16-pin TSSOP θ
JA
78 °C/W
20-pin TSSOP 68
28-pin SOIC 42
28-pin TSSOP 51
PRELIMINARY