©2003 Fairchild Semiconductor Corporation

www.fairchildsemi.com

Rev. 1.0.7

Features

• Programmable Output Voltage to 36 Volts

• Low Dynamic Output Impedance 0.20 Typical

• Sink Current Capability of 1.0 to 100mA

• Equivalent Full-Range Temperature Coefficient of

50ppm/

°C Typical

• Temperature Compensated for Operation Over Full Rated

Operating Temperature Range

• Low Output Noise Voltage

• Fast Turn-on Response

Description

The LM431A/LM431B/LM431C are three terminal output

adjustable regulators with thermal stability over operating

temperature range. The output voltage can be set any value

two external resistors. These devices have a typical dynamic

output impedance of 0.2

Ω Active output circuit provides a

sharp turn-on characteristic, making these devices excellent

replacement for Zener Diodes in many applications.

TO-92

8-DIP

8-SOP

1. Ref 2. Anode 3. Cathode

1

1

1

1.Cathode 2.3.6.7.Anode

4.5.NC 8.Ref

1.Cathode 2.3.4.5.7.NC

6.Anode 8.Ref

Internal Block Diagram

CATHODE

ANODE

REFERENCE

CATHODE (K)

ANODE (A)

REFERENCE (R)

2.5 Vref

LM431A/LM431B/LM431C

Programmable Shunt Regulator