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LTC1504

500mA Low Voltage

Step-Down Synchronous

Switching Regulator

Final Electrical Specifications

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.

However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-

tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Daisy-Chained Control Outputs

FEATURES

The LTC

chronous buck switching regulator. It includes a pair of

on-chip 1.5

Ω power switches, enabling it to supply up to

500mA of load current. Efficiency peaks at 92%, minimiz-

ing heat and wasted power. The synchronous buck archi-

tecture allows the output to source or sink current as

required to keep the output voltage in regulation.

The LTC1504 is available in adjustable and fixed 3.3V

output versions. An adjustable current limit circuit pro-

vides protection from overloads. The internal 1% refer-

ence combined with a sophisticated voltage feedback loop

provides optimum output voltage accuracy and fast load

transient response. The LTC1504 is specified to operate

with input voltages between 4V and 10V. Contact the LTC

factory for guaranteed specifications at 2.7V supply.

The LTC1504 is available in a plastic SO-8 package.

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500mA Output Current at 3.3V Output

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Up to 92% Peak Efficiency

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Internal Reference Trimmed to 1%

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Output Can Source or Sink Current

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Requires as Few as Four External Components

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Input Voltage Range: 4V to 10V

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Adjustable Current Limit

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Small SO-8 Package

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200kHz Switching Frequency Can be

Synchronized Up to 500kHz

Minimum Part Count 5V to 3.3V Regulator

5V to 3.3V Efficiency

LOAD CURRENT (mA)

10

100

90

80

70

60

50

40

30

20

10

0

100

500

1504 • TA02

SHDN

SS

COMP

GND

SW

SENSE

+

5V

SHUTDOWN

NC

NC

1000pF

+

3.3V AT 500mA

1504 • TA01

LTC1504-3.3

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

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Small Portable Digital Systems

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Active Termination

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Auxiliary Output Voltage Supplies

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Minimum Part Count/Size Switchers