mc9s12uf32 Freescale Semiconductor, Inc, mc9s12uf32 Datasheet - Page 101

• Manufacturer Part Number: mc9s12uf32
• Description: System Chip Guide V01.05
• Manufacturer: Freescale Semiconductor, Inc

A.1.8 Power Dissipation and Thermal Characteristics
Power dissipation and thermal characteristics are closely related. The user must assure that the maximum
operating junction temperature is not exceeded. The average chip-junction temperature (T
obtained from:
The total power dissipation can be calculated from:
Freescale Semiconductor
T
T A
P D
P INT
J
JA
NOTE:
Regulator Supply Voltage
VDDX Supply Voltage
VDD3X Supply Voltage
Digital Logic Supply Voltage
USB PHY Supply Voltage
Voltage Difference VSSX to VSSR and VSSA
Bus Frequency
Operating Junction Temperature Range
=
=
NOTES:
=
1. REF3V regulator channel cannot be used when VDD3X is not supplied by the regulated supply controlled by
2. The device contains an internal voltage regulator to generate the logic and USB PHY supply out of the VDDR.
=
Junction Temperature, [ C
REF3V.
The absolute maximum ratings apply when this regulator is disabled and the device is powered from an external
source.
Ambient Temperature, [ C
=
Total Chip Power Dissipation, [W]
Package Thermal Resistance, [ C/W]
Chip Internal Power Dissipation, [W]
Instead of specifying ambient temperature all parameters are specified for the more
meaningful silicon junction temperature. For power dissipation calculations refer
to Section A.1.8 Power Dissipation and Thermal Characteristics.
Rating
2
2
Table A-4 Operating Conditions
T
J
P D
=
T
=
A
P INT
+
Symbol
V
V
V
V
V
System on a Chip Guide — 9S12UF32DGV1/D V01.05
VSSX
f
DD3x
P
DDR
DDX
DDA
bus
T
DD
J
D
+
P IO
JA
Min
4.25
2.25
-0.1
3.0
3.0
3.0
0.5
0
Typ
5.0
5.0
3.3
2.5
3.3
0
-
-
Max
2.75
5.5
105
5.5
5.5
3.6
0.1
30
1
J
) in C can be
Unit
MHz
V
V
V
V
V
V
C
101