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LT1585A/LT1585A-3.3

5A Low Dropout

Fast Response

Positive Regulators

Adjustable and Fixed

The LT

regulators with 5A output current capability. Design has

been optimized for low voltage applications where tran-

sient response and minimum input voltage are critical.

Similar to the LT1084 family, these regulators feature

lower dropout voltage and faster transient response.

These improvements make them ideal for low voltage

microprocessor applications requiring a regulated 2.5V to

3.6V output with an input supply below 7V.

Current limit is trimmed to ensure specified output current

and controlled short-circuit current. On-chip thermal lim-

iting provides protection against any combination of over-

load that would create excessive junction temperatures.

The LT1585A/LT1585A-3.3 are available in the industry

standard 3-pin TO-220 power package.

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Fast Transient Response

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Guaranteed Dropout Voltage at Multiple Currents

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Load Regulation: 0.05% Typ

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Trimmed Current Limit

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On-Chip Thermal Limiting

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Standard 3-Pin Power Package

FEATURES

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Pentium

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PowerPC

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Other 2.5V to 3.6V Microprocessor Supplies

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Low Voltage Logic Supplies

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Battery-Powered Circuitry

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Post Regulator for Switching Supply

LT1585ACT

Adjustable

LT1585ACT-3.3

3.3V Fixed

, LTC and LT are registered trademarks of Linear Technology Corporation.

Pentium is a registered trademark of Intel Corporation. PowerPC is a trademark of IBM Corporation.

NOTE: MICROPROCESSOR APPLICATIONS WITH LOAD TRANSIENTS OF 3.8A REQUIRE

OUTPUT DECOUPLING CAPACITANCE >1300

µF ON FIXED VOLTAGE PARTS TO ACHIEVE

< 50mV OF DEVIATION FROM NOMINAL OUTPUT. CONSULT FACTORY FOR DETAILS

Dropout Voltage vs Output Current

3.3V, 5A Regulator

LT1585A-3.3

1585A TA01

C1

10

µF

* REQUIRED FOR STABILITY

3.3V

5A

+

C2*

10

µF

+

OUTPUT CURRENT (A)

0

1.5

1.4

1.3

1.2

1.1

1.0

0.9

0.8

0.7

0.6

0.5

LT1585A TA02