US431L/431AL
LOW -VOLTAGE ADJUSTABLE
PRECISION SHUNT REGULATOR
PRELIMINARY DATASHEET
FEATURES
SOT23-5 package
0.5% Voltage Reference Initial Accuracy
(US431AL)
Low Operational Cathode Current
(80 uA max)
Unconditionally Stable with only 1uF
Adjustable Output from 1.24V to 6V
0.25Ω Typical Output Impedance
Pin to Pin Compatible with TLV431
DESCRIPTION
The US431L product is a 3 terminal adjustable shunt
regulator that can also be used as a precision voltage
reference. Its output voltage may be set to any value
between Vref(1.24V) and 6V with two external resistors
as shown in the typical application circuit. Other appli-
cations of this device include the use as a merged am-
plifier and reference in applications such as Linear regu-
lator or as the secondary side controller in low voltage
power supply applications. The US431L only requires
80uA maximum quiescent current before regulating,
making it ideal as a voltage reference for battery type
applications.
APPLICATIONS
Precision Voltage Reference
Linear Regulator Controller
Secondary Side Controller for the Low Voltage
Power Supply Applications
TYPICAL APPLICATION
R
B
V
IN
R1
V
O
US431
R2
Co
R1
Vo
=
Vref
×
1
+
R2
431app1-1.0
Typical application of the US431L as a shunt regulator / voltage reference.
PACKAGE ORDER INFORMATION
Ta (°C)
0 TO 70
0 TO 70
5 LEAD
SOT23-5
US431LCL
US431ALCL
3 PIN PLASTIC
TO-92
US431LCZ
US431ALCZ
8 PIN PLASTIC
SOIC
US431LCS
US431ALCS
Rev. 1.2
5/11/98
2-1
UNISEM [ UNISEM ]
