1

Rev. 3/6/03

SPX2950/SPX2951 150mA Low Dropout Voltage Regulator

©Copyright 2003 Sipex Corporation

SPX2950/SPX2951

DESCRIPTION

FEATURES

■ 5.0V and 3.3V at 150mA Output

■ Accurate: 0.5% for SPX2950A/SPX2951A

■ Very Low Quiescent Current

■ Low Dropout Voltage: 300mV at 150mA

■ Extremely Tight Load and Line Regulation

■ Very Low Temperature Coefficient

■ Current & Thermal Limiting

■ Need Only 1µF for Stability

■ Offered in TO-92 (SPX2950) and SOIC

(SPX2951)

■ Direct Replacement for LP2950/LP2951

SPX2951 versions only

■ Error Flag Warns of Output Dropout

■ Logic-Controlled Electronic Shutdown

■ Output Programmable From 1.24 to 30V

®

The SPX2950 and SPX2951 are low power voltage regulators. These devices are an excellent choice for

use in battery-powered applications such as cordless telephones, radio control systems, and portable

computers. The SPX2950 and SPX2951 feature low quiescent current and low dropout voltage (typ. 20mV

at 100µA and 300mV at 150mA). This includes a tight initial tolerance of (0.5% for SPX2950A/SPX2951A),

extremely good load and line regulation (0.05% typ.), and very low output temperature coefficient (20ppm/

°C typ.), making the SPX2950/SPX2951 useful as a low-power voltage reference.

The error flag output feature is used as a power-on reset for warning of a low output voltage, due to a falling

voltage. The logic compatible shutdown feature enables the regulator to be switched ON and OFF. The

SPX2950 is offered in a 3-pin TO-92 package compatible with other 5.0V, 3.3V regulators. The SPX2951

is availiable in an 8-lead SOIC package.

150mA Low Dropout Voltage Regulator

Block Diagram of SPX2951, 8 Lead 5V Version

INPUT

OUTPUT

UNREGULATED DC

SHUTDOWN

GROUND

ERROR

______

SENSE

TO CMOS OR

TTL

REFERENCE

ERROR DETECTION

COMPARATOR

ERROR

AMPLIFIER

1.23V

FROM

CMOS OR

TTL

+

+

+

+

+

+

60 mV

3

7

8

1

2

6

5

4

60kΩ

330kΩ

180kΩ

.

.

1µF

_

_

FEEDBACK

5V TAP

5V

APPLICATIONS

■ Battery Powered Systems

■ Cordless Telephones

■ Radio Control Systems

■ Portable/Palm Top/Notebook Computers

■ Portable Consumer Equipment

■ Portable Instrumentation

■ Avionics

■ SMPS Post-Regulator

■ Voltage Reference

■ Automotive Electronics