AM186ED Datasheet, PDF (51/88 Pages) Advanced Micro Devices – High Performance, 80C186- and 80C188-Compatible, 16-Bit Embedded Microcontrollers

PRELIMINARY
THERMAL CHARACTERISTICS
TQFP Package
The Am186ED microcontroller is specified for
operation with case temperature ranges from 0°C to
+100°C for a commercial device. Case temperature is
measured at the top center of the package as shown in
Figure 13. The various temperatures and thermal
resistances can be determined using the equations in
Figure 14 with information given in Table 11.
The total thermal resistance is θ_JA; θ_JA is the sum of
θ_JC, the internal thermal resistance of the assembly,
and θ_CA, the case to ambient thermal resistance.
The variable P is power in watts. Power supply current
(I_CC) is in mA per MHz of clock frequency.
θ_JA
θ_CA
T_{C θJC}
θ_JA = θ_JC + θ_CA
Figure 13. Thermal Resistance(°C/Watt)
θ_PJ=AIC=_Cθ_{⋅JCfre+q}θ_{(CMAHz) ⋅ VCC}
T_J
T_J
=
=
T_C +(
T_A+ (
PP⋅⋅θθ_JJCA
)
)
T_C
T_C
=
=
T_J – (
T_A +(
PP⋅⋅θθ_JCCA
)
)
T_A
T_A
=
=
T_J – (
T_C – (
PP⋅⋅θθ_JCAA))
F ^{Figure 14. Thermal Characteristics Equations}
Table 11. Thermal Characteristics (°C/Watt)
Airflow
(Linear Feet
A _{Package/Board per Minute)}
θ_JA
θ_JC
θ_CA
PQFP/2-Layer
0 fpm
45
7
38
200 fpm
39
7
32
400 fpm
35
7
28
R_{600 fpm}
33
7
26
TQFP/2-Layer
0 fpm
56
10
46
200 fpm
46
10
36
D ^400fpm
40
10
30
600 fpm
38
10
28
PQFP/4-Layer
to 6-Layer
0 fpm
200 fpm
23
5
18
21
5
16
400 fpm
19
5
14
600 fpm
17
5
12
TQFP/4-Layer
to 6-Layer
0 fpm
200 fpm
30
6
24
28
6
22
400 fpm
26
6
20
600 fpm
24
6
18
T
Am186ED/EDLV Microcontrollers
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