1 Features

1• Low-Voltage Operation/Wide Adjust Range

(1.24 V/30 V)

• 0.5% Initial Tolerance (LMV431B)

• Temperature Compensated for Industrial

Temperature Range (39 PPM/°C for the

LMV431AI)

• Low Operation Current (55 μA)

• Low Output Impedance (0.25 Ω)

• Fast Turn-On Response

• Low Cost

2 Applications

• Shunt Regulator

• Series Regulator

• Current Source or Sink

• Voltage Monitor

• Error Amplifier

• 3-V Off-Line Switching Regulator

• Low Dropout N-Channel Series Regulator

3 Description

The LMV431, LMV431A and LMV431B are precision

1.24 V shunt regulators capable of adjustment to 30

V. Negative feedback from the cathode to the adjust

pin controls the cathode voltage, much like a non-

inverting op amp configuration (Refer to Symbol and

Functional Diagrams). A two-resistor voltage divider

terminated at the adjust pin controls the gain of a

1.24 V band-gap reference. Shorting the cathode to the adjust pin (voltage follower) provides a cathode

voltage of a 1.24 V.

The LMV431, LMV431A and LMV431B have

respective initial tolerances of 1.5%, 1%, and 0.5%,

and functionally lend themselves to several

applications that require zener diode type

performance at low voltages. Applications include a 3 V to 2.7 V low drop-out regulator, an error amplifier in

a 3 V off-line switching regulator and even as a

voltage detector. These parts are typically stable with

capacitive loads greater than 10 nF and less than 50

pF.

The LMV431, LMV431A and LMV431B provide

performance at a competitive price.