Now Available in Lead Free Packaging

Rev. 8/10/01

LP2950/51 100mA Low Dropout Voltage Regulators

©Copyright 2001 Sipex Corporation

1

INPUT

OUTPUT

UNREGULATED DC

SHUTDOWN

GROUND

ERROR

______

SENSE

5V @ 100mA

MAX

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

60k

Ω

330k

Ω

180k

Ω

.

.

1

µF

_

_

FEEDBACK

5V TAP

LP2950/LP2951

100mA Low Dropout Voltage Regulators

FEATURES

APPLICATIONS

• 5.0V and 3.3V Versions at 100mA Output

• Battery Powered Systems

• Very Low Quiescent Current

• Cordless Telephones

• Low Dropout Voltage: 380mV at 100mA

• Radio Control Systems

• Extremely Tight Load and Line Regulation

• Portable/Palm Top/Notebook Computers

• Very Low Temperature Coefficient

• Portable Consumer Equipment

• Current & Thermal Limiting

• Portable Instrumentation

• Need Only 1 µF for Stability

• Avionics

• Offered in TO-92 (LP2950) & SOIC (LP2951)

• SMPS Post-Regulator

• Direct Replacement For LP2950/LP2951

• Voltage Reference

• Automotive Electronics

LP2951 versions only

• Error Flag Warns of Output Dropout

• Logic-Controlled Electronic Shutdown

• Output Programmable From 1.24 to 29V

PRODUCT DESCRIPTION

The LP2950 and LP2951 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 LP2950 and LP2951 feature low

quiescent current and low dropout voltage (typ. 50mV at light load and 380 mV at 100mA). This includes a tight initial tolerance

(0.5% typ.), extremely good load and line regulation (0.05% typ.), and very low output temperature coefficient (20 ppm/¡C typ.),

making the LP2950/LP2951 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 input voltage. The logic-

compatible shutdown feature enables the regulator to be switched ON and OFF. The LP2950 is offered in a 3-pin TO-92 package

compatible with other 5V, 3.3V regulators. The LP2951 is available in an 8-lead SOIC package.

Block diagram of LP2951