MC9S12A128 MOTOROLA [Motorola, Inc], MC9S12A128 Datasheet - Page 62

• Manufacturer Part Number: MC9S12A128
• Description: Microcontroller unit (MCU)
• Manufacturer: MOTOROLA [Motorola, 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:
T
T
P
The total power dissipation can be calculated from:
P
Two cases with internal voltage regulator enabled and disabled must be considered:
J
A
D
INT
JA
1. Internal Voltage Regulator disabled
=
P
For R
respectively
=
=
IO
=
Junction Temperature, [ C
Ambient Temperature, [ C
=
Total Chip Power Dissipation, [W]
is the sum of all output currents on I/O ports associated with V
Package Thermal Resistance, [ C/W]
Chip Internal Power Dissipation, [W]
DSON
is valid:
P
INT
R
DSON
=
I
R
DD
DSON
=
V
P
DD
V
----------------------------------- - for outputs driven high
T
IO
DD5
J
=
P
+
=
D
=
I
V
----------- - for outputs driven low
I
I
OH
DDPLL
OL
OL
T
–
=
A
i
V
P
;
OH
+
R
INT
DSON
P
;
D
V
+
DDPLL
P
IO
JA
I
IO i
2
+
I
MC9S12A128 Device Guide — V01.01
DDA
DDX
V
and V
DDA
DDR
.
J
) in C can be
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