LP3962/LP3965

1.5A Fast Ultra Low Dropout Linear Regulators

General Description

The LP3962/LP3965 series of fast ultra low-dropout linear

regulators operate from a +2.5V to +7.0V input supply. Wide

range of preset output voltage options are available. These

ultra low dropout linear regulators respond very fast to step

changes in load which makes them suitable for low voltage

microprocessor applications. The LP3962/LP3965 are de-

veloped on a CMOS process which allows low quiescent

current operation independent of output load current. This

CMOS process also allows the LP3962/LP3965 to operate

under extremely low dropout conditions.

Dropout Voltage: Ultra low dropout voltage; typically 38mV

at 150mA load current and 380mV at 1.5A load current.

Ground Pin Current: Typically 5mA at 1.5A load current.

Shutdown Mode: Typically 15µA quiescent current when

the shutdown pin is pulled low.

Error Flag: Error flag goes low when the output voltage

drops 10% below nominal value (for LP3962).

SENSE: Sense pin improves regulation at remote loads.

(For LP3965)

Precision Output Voltage: Multiple output voltage options

are available ranging from 1.2V to 5.0V and adjustable

load, and temperature).

Features

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Ultra low dropout voltage

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Low ground pin current

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Load regulation of 0.04%

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15µA quiescent current in shutdown mode

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Guaranteed output current of 1.5A DC

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Available in SOT-223,TO-263 and TO-220 packages

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Error flag indicates output status (LP3962)

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Sense option improves better load regulation (LP3965)

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Extremely low output capacitor requirements

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Overtemperature/overcurrent protection

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

Applications

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Microprocessor power supplies

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GTL, GTL+, BTL, and SSTL bus terminators

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Power supplies for DSPs

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SCSI terminator

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Post regulators

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High efficiency linear regulators

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Battery chargers

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Other battery powered applications

Typical Application Circuits

10126601

*SD and ERROR pins must be pulled high through a 10k

Ω pull-up resistor. Connect the ERROR pin to ground if this function is not used. See applications

section for more information.

** See Application Hints.

November 2001

© 2001 National Semiconductor Corporation

DS101266

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