S912XEG128J2VAL
Model | S912XEG128J2VAL |
Description | IC,MICROCONTROLLER,16-BIT,CPU12 CPU,CMOS,QFP,112PIN,PLASTIC |
PDF file | Total 1327 pages (File size: 7M) |
Chip Manufacturer | ROCHESTER |
Appendix A Electrical Characteristics
A.1.8
Power Dissipation and Thermal Characteristics
Because of an order from the United States International Trade Commission, BGA-packaged product lines and part numbers indicated here currently are not
available from Freescale for import or sale in the United States prior to September 2010: S12XE products in 208 MAPBGA packages
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
J
) in
°C
can be
obtained from:
T
T
T
J
A
D
= Junction Temperature, [°C
]
= Ambient Temperature, [°C
]
= Total Chip Power Dissipation, [W]
= Package Thermal Resistance, [°C/W]
J
= T +
(
P
• Θ )
A
D
JA
P
Θ
JA
The total power dissipation can be calculated from:
P
P
D
= P
INT
+P
IO
INT
= Chip Internal Power Dissipation, [W]
P
IO
=
∑
i
R
DSON
⋅
I
2
IO i
P
IO
is the sum of all output currents on I/O ports associated with V
DDX
, whereby
V
OL
= ----------- ;for outputs driven low
-
R
DSON
I
OL
V
–
V
DD35
OH
R
= --------------------------------------- ;for outputs driven high
DSON
I
OH
Two cases with internal voltage regulator enabled and disabled must be considered:
1. Internal voltage regulator disabled
P
INT
= I
DD
⋅
V
DD
+I
DDPLL
⋅
V
DDPLL
+I
DDA
⋅
V
DDA
2. Internal voltage regulator enabled
P
INT
= I
DDR
⋅
V
DDR
+
I
DDA
⋅
V
DDA
MC9S12XE-Family Reference Manual Rev. 1.19
Freescale Semiconductor
1207