AM186 Datasheet, PDF (66/112 Pages) Advanced Micro Devices – High-Performance, 80C186- and 80C188-Compatible, 16-Bit Embedded Microcontrollers with RAM

Table 16 shows typical maximum ambient temperatures in degrees Centigrade for a TQFP package used with a
4-layer to 6-layer board. The typical ambient temperatures are based on a 100-degree Centigrade maximum case
temperature. Figure 21 illustrates the typical temperatures in Table 16.
Table 16. Typical Ambient Temperatures for TQFP with Four-Layer to Six-Layer Board
Microcontroller
Speed
50 MHz
40 MHz
33 MHz
25 MHz
Typical Power
(Watts)
0.662
0.522
0.432
0.342
0 fpm
84.1
87.44
89.64
91.84
Linear Feet per Minute Airflow
200 fpm
400 fpm
85.5
86.8
88.5
89.5
90.5
91.4
92.5
93.2
600 fpm
88.1
90.6
92.2
93.9
97
96
95
94
93
92
x
91
90
I
89
Legend:
D88
q
87
86
s 50 MHz
q 40 MHz
85
H 33 MHz
x 25 Mhz
84
s
0 fpm
T^x
x
x
F^I
I
I
q
A_q
q
R^s
s
s
200 fpm
400 fpm
600 fpm
Airflow (Linear Feet Per Minute)
Figure 21. Typical Ambient Temperatures for TQFP with Four-Layer to Six-Layer Board
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Am186^TMER and Am188^TMER Microcontrollers Data Sheet