US431ALCS UNISEM [UNISEM], US431ALCS Datasheet - Page 5

• Manufacturer Part Number: US431ALCS
• Description: LOW -VOLTAGE ADJUSTABLE PRECISION SHUNT REGULATOR
• Manufacturer: UNISEM [UNISEM]

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
stable for any cathode current if the capacitor, C
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-
tions , the C
be stable.
Rev. 1.2
5/11/98
P
P
For our example :
P
Where :
MAX
MAX
MAX
3 3
V
Maximum power dissipation of the 431L
.
KA
O
can be cut to 0.01uF and the system will
6
V
100
MAX
- 3.3
R
- V
B
KA
89
mW
O
=
US431L/431AL
2-5