P R E L I M I N A R Y
Table 14 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 20 illustrates the typical temperatures in Table 14.
Table 14. Typical Ambient Temperatures for TQFP with 4-Layer to 6-Layer Board
Linear Feet per Minute Airflow
Microcontroller
Speed
Typical Power
(Watts)
0 fpm
70.264
74.2996
80.53
200 fpm
72.742
400 fpm
75.22
600 fpm
77.698
40 MHz
33 MHz
25 MHz
20 MHz
1.239
1.07085
0.81125
0.649
76.4413
82.1525
85.722
78.583
83.775
87.02
80.7247
85.3975
88.318
84.424
95
90
85
80
■
◆
■
◆
■
◆
■
◆
✶
●
✶
●
✶
●
Legend:
75
70
● 40 MHz
✵ 33 MHz
✶
◆ 25 Mhz
■ 20 MHz
●
0 fpm
200 fpm
600 fpm
400 fpm
Airflow (Linear Feet Per Minute)
Figure 20. Typical Ambient Temperatures for TQFP with 4-Layer to 6-Layer Board
Am186/188EM and Am186/188EMLV Microcontrollers
59
AMD [ AMD ]
