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LT1580/LT1580-2.5

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Low Dropout, 540mV at 7A Output Current

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Fast Transient Response

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Remote Sense

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1mV Load Regulation

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Fixed 2.5V Output and Adjustable Output

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No Supply Sequencing Problems in

Dual Supply Mode

The LT ®1580 is a 7A low dropout regulator designed to

power the new generation of microprocessors. The drop-

out voltage of this device is 100mV at light loads rising to

just 540mV at 7A. To achieve this dropout, a second low

current input voltage 1V greater than the output voltage, is

required. The device can also be used as a single supply

device where dropout is comparable to an LT1584.

Several other new features have been added to the LT1580.

A remote SENSE pin is brought out. This feature virtually

eliminates output voltage variations due to load changes.

Typical load regulation, measured at the SENSE pin, for a

load current step of 100mA to 7A is less than 1mV.

The LT1580 has fast transient response, equal to the

LT1584. On fixed voltage devices, the ADJ pin is brought

out. A small capacitor on the ADJ pin further improves

transient response.

This device is ideal for generating processor supplies of

2V to 3V on motherboards where both 5V and 3.3V

supplies are available.

7A, Very Low

Dropout Regulator

FEATURES

, 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.

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Microprocessor Supplies

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Post Regulators for Switching Supplies

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High Current Regulators

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5V to 3.XXV for Pentium

at 90MHz to 166MHz and Beyond

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3.3V to 2.9V for Portable Pentium Processor

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PowerPC

OUTPUT CURRENT (A)

0

1.0

0

1

5

7

1580 G03

4

2

3

6

0.5

DATA SHEET LIMIT

INDICATES GUARANTEED TEST POINTS

0

Dropout Voltage —

Minimum Power Voltage

2.5V Microprocessor Supply

SENSE

ADJ

GND

0.1

µF

1580 TA01

10

µF

TANT

330

µF

OS-CON

2.5V/7A

LT1580-2.5

100

µF TANT

AVX TPS

× 7

3.3V

7A

5V

0.2A

+

+

+