LP3995

Micropower 150mA CMOS Voltage Regulator with Active

Shutdown

General Description

The LP3995 linear regulator is designed to meet the require-

ments of portable battery-powered applications and will pro-

vide an accurate output voltage with low noise and low

quiescent current. Ideally suited for powering RF/Analog

devices, this device will also be used to meet more general

circuit needs in which a fast turn-off is essential.

For battery powered applications the low dropout and low

ground current provided by the device allows the lifetime of

the battery to be maximized. The Enable(/Disable) control

allows the system to further extend the battery lifetime by

reducing the power consumption to virtually zero.

The Enable(/Disable) function on the device incorporates an

active discharge circuit on the output for faster device shut-

down. Where the fast turn-off is not required the LP3999

linear regulator is recommended.

The LP3995 also features internal protection against short-

circuit currents and over-temperature conditions.

The LP3995 is designed to be stable with small 1.0 µF

ceramic capacitors. The small outline of the LP3995 micro

SMD package with the required ceramic capacitors can

realize a system application within minimal board area.

Performance is specified for a −40˚C to +125˚C temperature

range.

The device is available in micro SMD package and LLP

package. For other package options contact your local NSC

sales office.

The device is available in fixed output voltages in the ranges

1.5V to 3.3V. For availability, please contact your local NSC

sales office.

Key Specifications

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2.5V to 6.0V Input Range

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60 mV Typical Dropout with 150 mA Load

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Virtually Zero Quiescent Current when Disabled

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Low Output Voltage Noise

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Stable witha1µF Output Capacitor

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Guaranteed 150 mA Output Current

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Fast Turn-on; 30 µs (Typ.)

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Fast Turn-off; 175 µs (Typ.)

Features

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5 pin micro SMD Package

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6 pin LLP Package

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Stable with Ceramic Capacitor

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Logic Controlled Enable

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Fast Turn-on

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Active Disable for Fast Turn-off.

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Thermal-overload and Short-circuit Protection

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−40 to +125˚C Junction Temperature Range for

Operation

Applications

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GSM Portable Phones

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CDMA Cellular Handsets

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Wideband CDMA Cellular Handsets

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Bluetooth Devices

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Portable Information Appliances

Typical Application Circuit

20034901

August 2004

© 2004 National Semiconductor Corporation

DS200349

www.national.com