LP3984

Micropower, 150mA Ultra Low-Dropout CMOS Voltage

Regulator in Subminiature 4-I/O micro SMD Package

General Description

The LP3984 is designed for portable and wireless applica-

tions with demanding performance and space requirements.

The LP3984’s performance is optimized for battery powered

systems to deliver extremely low dropout voltage and low

quiescent current. Regulator ground current increases only

slightly in dropout, further prolonging the battery life.

Power supply rejection is better than 60 dB at low frequen-

cies and starts to roll off at 10 kHz. High power supply

rejection is maintained down to lower input voltage levels

common to battery operated circuits.

The device is ideal for mobile phone and similar battery

powered wireless applications. It provides up to 150 mA,

from a 2.5V to 6V input, consuming less than 1.2µA in

disable mode and has fast turn-on time less than 20µs.

The LP3984 is available in micro SMD and 5 pin SOT-23

package. Performance is specified for −40˚C to +125˚C

temperature range and is available in 1.5V, 1.8V, 2.0V, and

3.1V output voltages. For other output voltage options from

1.5V to 3.5V, please contact National Semiconductor sales

office.

Key Specifications

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2.5 to 6.0V input range

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150mA guaranteed output

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IN

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≤1.2µA quiescent current when shut down

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Fast Turn-On time: 20 µs (typ.)

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75mV typ dropout with 150mA load

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−40 to +125˚C junction temperature range for operation

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1.5V, 1.8V, 2.0V, and 3.1V

Features

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Miniature 4-I/O micro SMD and SOT-23-5 package

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Logic controlled enable

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Stable with tantalum capacitors

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1 µF Tantalum output capacitor

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Fast turn-on

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Thermal shutdown and short-circuit current limit

Applications

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CDMA cellular handsets

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Wideband CDMA cellular handsets

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GSM cellular handsets

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Portable information appliances

Typical Application Circuit

20020402

Note: Pin Numbers in parenthesis indicate micro SMD package.

November 2001

© 2001 National Semiconductor Corporation

DS200204

www.national.com