Rev 2

8

November 2005

1/8

TS4431

1.224V Open Collector Shunt Voltage Reference

75 mV max between SINK and GND

µA

Description

The TS4431 is a four-terminal device dedicated to

low voltage Switch Mode Power Supplies (SMPS).

It integrates a 1.224V voltage reference, an

amplifier, and an open collector output transistor

in a single package. The TS4431’s operating

mode is similar to the well-known standard

voltage reference, the TL431. It maintains the

desired feedback voltage at the REF pin in a

closed loop configuration by sinking a current

proportional to the error voltage at the REF pin.

TS4431 features an open collector transistor with

an ultra-low saturation voltage, allowing it to be

used in series with the optocoupler in an SMPS

architecture to regulate low voltage SMPS.

Applications

Order Codes

SOT23-5L

(Plastic Micropackage)

Pin connections (top view)

1

2

34

5

Vc c

Gnd

Nc

Ref

Sink

Part Number

Accuracy

Temperature Range

Package

Packing

Marking

TS4431AILT

0.5%

-40, +85°C

SOT23-5

Tape & Reel

L288

TS4431ILT

1%

L275

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