TIBPAL20L8-5C Datasheet, PDF (20/35 Pages) Texas Instruments – HIGH-PERFORMANCE IMPACT-X PAL CIRCUITS

TIBPAL20R8-5C
HIGH-PERFORMANCE IMPACT-X ™ PAL^® CIRCUITS
SRPS010F – D3353, OCTOBER 1989 – REVISED SEPTEMBER 1992
THERMAL INFORMATION
thermal management of the TIBPAL20R8-5C
Thermal management of the TIBPAL20R8-5CNT and TIBPAL20R8-5CFN is necessary when operating at
certain conditions of frequency, output loading, and outputs switching simultaneously. The device and system
application will determine the appropriate level of management.
Determining the level of thermal management is based on factors such as power dissipation (P_D), ambient
temperature (T_A), and transverse airflow (FPM). Figures 6 (a) and 6 (b) show the relationship between ambient
temperature and transverse airflow at given power dissipation levels. The required transverse airflow can be
determined at a particular ambient temperature and device power dissipation level in order to ensure the device
specifications.
Figure 7 illustrates how power dissipation varies as a function of frequency and the number of outputs switching
simultaneously. It should be noted that all outputs are fully loaded (C_L = 50 pF). Since the condition of eight fully
loaded outputs represents the worst-case condition, each application must be evaluated accordingly.
1000
MINIMUM TRANSVERSE AIR FLOW
vs
AMBIENT TEMPERATURE
1000
MINIMUM TRANSVERSE AIR FLOW
vs
AMBIENT TEMPERATURE
800
600
PD = 1.6 W
PD = 1.4 W
PD = 1.2 W
PD = 1 W
400
PD = 0.8 W
PD = 0.6 W
200
800
600
PD = 1.6 W
PD = 1.4 W
PD = 1.2 W
PD = 1 W
PD = 0.8 W
400
PD = 0.6 W
200
0
0 10 20 30 40 50 60 70 80
TA – Ambient Temperature – °C
(a) TIBPAL20-5CNT
Figure 6
0
0 10 20 30 40 50 60 70 80
TA – Ambient Temperature – °C
(b) TIBPAL20R8-5CFN
20
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