LT1431
Programmable Reference
U
5V
V
+
R
TOP
+
gm =
4mA/V
–
R
MID
REF
2.5V
LT1431
GND-S
LT1431 • TA01
FEATURES
s
s
s
s
s
DESCRIPTIO
Guaranteed 0.4% Initial Voltage Tolerance
0.1Ω Typical Dynamic Output Impedance
Fast Turn-On
Sink Current Capability, 1mA to 100mA
Low Reference Pin Current
APPLICATI
s
s
s
S
Linear Regulators
Adjustable Power Supplies
Switching Power Supplies
The LT1431 is an adjustable shunt voltage regulator with
100mA sink capability, 0.4% initial reference voltage tol-
erance, and 0.3% typical temperature stability. On-chip
divider resistors allow the LT1431 to be configured as a 5V
shunt regulator, with 1% initial voltage tolerance and
requiring no additional external components. By adding
two external resistors, the output voltage may be set to any
value between 2.5V and 36V. The nominal internal current
limit of 100mA may be decreased by including one exter-
nal resistor.
A simplified three pin version, the LT1431Z/IZ, is available
for applications as an adjustable reference and is pin
compatible with the TL431.
TYPICAL APPLICATI
+
V
IN
SWITCHING
REGULATOR
–
UO
UO
Isolated 5V Regulator
+
COLL
COMP
GND-F
1
LINER [ LINEAR TECHNOLOGY ]
