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LM431A/LM431B/LM431C
Programmable Shunt Regulator
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
between V
REF
(approximately 2.5 volts) and 36 volts with
two external resistors. These devices have a typical dynamic
output impedance of 0.2Ω Active output circuit provides a
sharp turn-on characteristic, making these devices excellent
replacement for Zener Diodes in many applications.
TO-92
1
1. Ref 2. Anode 3. Cathode
8-DIP
8-SOP
1
1
1.Cathode 2.3.4.5.7.NC
6.Anode 8.Ref
1.Cathode 2.3.6.7.Anode
4.5.NC 8.Ref
Internal Block Diagram
REFERENCE
CATHODE
2.5 Vref
ANODE
CATHODE (K)
REFERENCE (R)
ANODE (A)
Rev. 1.0.7
©2003 Fairchild Semiconductor Corporation