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LTC3413

sn3413 3413fs

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO

3A, 2MHz Monolithic

Synchronous Regulator for

DDR/QDR Memory Termination

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High Efficiency: Up to 90%

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±3A Output Current

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Symmetrical Source and Sink Output Current Limit

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No Schottky Diode Required

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2.25V to 5.5V Input Voltage Range

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±1% Output Voltage Accuracy

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Programmable Switching Frequency: Up to 2MHz

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Power Good Output Voltage Monitor

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Overtemperature Protected

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Available in 16-Lead TSSOP Exposed Pad Package

The LTC

nous step-down DC/DC converter utilizing a constant

frequency, current mode architecture. It operates from an

input voltage range of 2.25V to 5.5V and provides a

or sinking up to 3A of output current. An internal voltage

divider reduces component count and eliminates the need

for external resistors by dividing the reference voltage in

half. The internal synchronous power switch with 85m

Ω

on-resistance increases efficiency and eliminates the need

for an external Schottky diode. Switching frequencies up

to 2MHz are set by an external resistor.

Forced-continuous operation in the LTC3413 reduces

noise and RF interference. Fault protection is provided by

an overcurrent comparator that limits output current dur-

ing both sourcing and sinking operations. Adjustable

compensation allows the transient response to be opti-

mized over a wide range of loads and output capacitors.

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Bus Termination: DDR and QDR

SSTL, HSTL, ...

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Notebook Computers

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Distributed Power Systems

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

Figure 1a. High Efficiency Bus Termination Supply

Figure 1b. Efficiency vs Load Current

PGOOD

SW

22

µF

4.7M

309k

L1: VISHAY DALE IHLP-2525CZ-01 0.47

2.5V

100

µF

×2

3413 F01a

1.25V

±3A

L1

0.47

µH

LTC3413

PGND

RUN/SS

SGND

330pF

2200pF

5.11k

LOAD CURRENT (A)

0.01

40

50

60

70

80

0.1

1

10

3413 F01b

30

20

10

0

90

100

f = 1MHz

QDR RAMs and Quad Data Rate RAMs comprise a new family of products developed by Cypress

Semiconductor, Hitachi, IDT, Micron Technology, Inc. and Samsung.