80C186EB/80C188EB, 80L186EB/80L188EB
PACKAGE THERMAL
SPECIFICATIONS
The 80C186EB/80L186EB is specified for operation
when T
C
(the case temperature) is within the range
of
b
40
§
C to
a
100
§
C (PLCC package) or
b
40
§
C to
a
114
§
C (QFP package). T
C
may be measured in
any environment to determine whether the proces-
sor is within the specified operating range. The case
temperature must be measured at the center of the
top surface.
T
A
(the ambient temperature) can be calculated
from
i
CA
(thermal resistance from the case to ambi-
ent) with the following equation:
T
A
e
T
C
b
P
*
i
CA
Typical values for
i
CA
at various airflows are given
in Table 10. P (the maximum power consumption,
specified in watts) is calculated by using the maxi-
mum ICC as tabulated in the DC specifications and
V
CC
of 5.5V.
Table 10. Thermal Resistance (
i
CA
) at Various Airflows (in
§
C/Watt)
Airflow Linear ft/min (m/sec)
0
200
400
600
800
1000
(0) (1.01) (2.03) (3.04) (4.06) (5.07)
i
CA
(PLCC)
30
24
21
19
17
16.5
i
CA
(QFP)
58
47
43
40
38
36
i
CA
(SQFP)
70
TBD
TBD
TBD
TBD
TBD
22