Rev. 11/21/00

ALPHA

AS2930

1

8-Pin Surface Mount

Top View

2

3

4

5

6

7

8

SPX2955

OUTPUT

SENSE

SHUTDOWN

GROUND

INPUT

FEEDBACK

5V/ 3.3V TAP

ERROR

SPX2955/56/57

350mA Low Drop Out Voltage Regulator

with Shutdown

(PRELIMINARY INFORMATION)

FEATURES

APPLICATIONS

• Output Accuracy 5V, 3.3V@ 350mA Output

• Battery Powered Systems

• Very Low Quiescent Current

• Cordless Telephones

• Low Dropout Voltage

• 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

• Error Flag Warns Of Output Dropout

• Automotive Electronics

• Logic-Controlled Electronic Shutdown

• SMPS Post-Regulator

• Output Programmable From 1.24V to 29V

• Voltage Reference

PRODUCT DESCRIPTION

The SPX2955/56/57 is a low power voltage regulator. This device is an excellent choice for use in battery-powered applications such

as cordless telephones, radio control systems, and portable computers. The SPX2955/56/57 features very low quiescent current

(100

µA Typ.) and very low dropout voltage. This includes a tight initial tolerance of 1% max and 2% max., and very low output

temperature coefficient, making the SPX2955/56/57 useful as a low-power voltage reference.

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

Another feature is the logic-compatible shutdown input which enables the regulator to be switched on and off. The SPX2955/56/57 is

offered in 3-pin and 5-pin TO-220 package compatible with other 5 volt and adjustable regulators, in 8-Pin Plastic Dip SO-8 (same pin

out as SPX2951) and surface mount TO-263 packages.

The regulator output voltage (of the 8-pin package and 5-pin TO-220 & TO-263) may be pin-strapped for a 5V and 3.3V or

programmed from 1.24V to 29V with an external pair of resistors. Look for SPX2951 for 150mA and SPX2954 for 250mA

applications.

PIN CONNECTIONS

TO-263-5 Package

Top View

12 3 4 5

SPX2956/57

INPUT

GND

INPUT

ERROR

OUTPUT

GND

Five Lead Package Pin Functions:

1)

SPX2956

SPX2957

3)

4)

5)

ADJUST

SHUTDOWN

OUTPUT

SHUTDOWN

2)

Front View

3

2

1

TO-263-3 Package

V

OUT

GND

V

IN

SPX2955

Top View

SPX2956/57

TO-220-5 Package

5

4

3

2

1

Front View

TO-220-3 Package

1

2

3

GND

V

IN