REV. A

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a

ADP3308

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

World Wide Web Site: http://www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 1998

anyCAP™ 50 mA

Low Dropout Linear Regulator

FUNCTIONAL BLOCK DIAGRAM

CC

OUT

GND

R1

R2

Q1

IN

SD

ADP3308

BANDGAP

REF

Q2

ERR/NC

DRIVER

THERMAL

PROTECTION

Gm

FEATURES

1.2% Accuracy Over Line and Load Regulations

@ 25 C

Ultralow Dropout Voltage: 80 mV Typical @ 50 mA

F for Stability

anyCAP = Stable with All Types of Capacitors

(Including MLCC)

Current and Thermal Limiting

Low Noise

Low Shutdown Current: 1

A

3.0 V to 12 V Supply Range

–20 C to +85 C Ambient Temperature Range

Several Fixed Voltage Options

Ultrasmall SOT-23-5 Package

Excellent Line and Load Regulations

APPLICATIONS

Cellular Telephones

Notebook, Palmtop Computers

Battery Powered Systems

PCMCIA Regulator

Bar Code Scanners

Camcorders, Cameras

GENERAL DESCRIPTION

The ADP3308 is a member of the ADP330x family of precision

low dropout anyCAP voltage regulators. It is pin-for-pin and

functionally compatible with National’s LP2980, but offers

performance advantages. The ADP3308 stands out from the

conventional LDOs with a novel architecture and an enhanced

process. Its patented design requires only a 0.47

µF output

capacitor for stability. This device is stable with any type of

capacitor regardless of its ESR (Equivalent Serial Resistance)

value, including ceramic types for space restricted applications.

The ADP3308 achieves

±1.2% accuracy at room temperature

and

± 2.2% overall accuracy over temperature, line and load

regulations. The dropout voltage of the ADP3308 is only

80 mV (typical) at 50 mA. This device also includes a current

limit and a shutdown feature. In shutdown mode, the ground

current is reduced to ~1

µA.

The ADP3308 operates with a wide input voltage range from

3.0 V to 12 V and delivers a load current in excess of 100 mA.

The ADP3308 anyCAP LDO offers a wide range of output

voltages. For 100 mA version, refer to the ADP3309 data sheet.

anyCAP is a trademark of Analog Devices, Inc.

ADP3308-3.3

OUT

IN

GND

ON

OFF

5

SD

C1

0.47 F

C2

0.47 F

ERR/NC

1

2

3

4

Figure 1. Typical Application Circuit