US431L/431AL

2-5

Rev. 1.2

5/11/98

In our previous example, the maximum power dissipa-

tion of the device is calculated under no load and maxi-

mum input supply condition.

The maximum power is calculated using the following

equation :

As shown in the power dissipation table, both packages

can handle this power dissipation.

Stability

The US431L has many different regions of stability do-

main as a function of the cathode current which are typi-

cal characteristics of the 3 terminal shunt regulators.

However in general the device will be unconditionaly

1 uF or bigger is connected from Cathode to Anode

pins. If the cathode current is always kept higher than

500uA under minimum line and maximum load condi-

be stable.

P

V

V

Where :

P

P

MAX

KA

MAX

MAX

MAX

=

× 







=

=

× 







=

- V

R

Maximum power dissipation of the 431L

For our example :

- 3.3

100

mW

KA

B

3 3

6

89

.