
Electrical Specifications
MC68HC908QL4 MC68HC908QL3 MC68HC908QL2 Data Sheet, Rev. 4
204
Freescale Semiconductor
17.3 Functional Operating Range
17.4 Thermal Characteristics
Characteristic
Symbol
Value
Unit
Temperature
Code
Operating temperature range
T
A
(T
L
to T
H
)
–40 to +125
–40 to +105
–40 to +85
°
C
M
V
C
Operating voltage range
V
DD
3.0 to 5.5
V
—
Characteristic
Symbol
Value
Unit
Thermal resistance
16-pin SOIC
16-pin TSSOP
θ
JA
90
133
°
C/W
I/O pin power dissipation
P
I/O
User determined
W
Power dissipation
(1)
1. Power dissipation is a function of temperature.
2. K constant unique to the device. K can be determined for a known T
A
and measured
P
D.
With this value of K, P
D
and T
J
can be determined for any value of T
A
.
P
D
P
D
= (I
DD
x V
DD
)
+ P
I/O
= K/(T
J
+ 273
°
C)
P
D
x
(T
+ 273
°
C)
+ P
A
x
θ
JA
T
A
+ (P
D
x
θ
JA
)
W
Constant
(2)
K
W/
°
C
Average junction temperature
T
J
°
C
Maximum junction temperature
T
JM
150
°
C