LM3485

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SNVS178G – JANUARY 2002 – REVISED FEBRUARY 2013

Hysteretic PFET Buck Controller

Check for Samples: LM3485

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FEATURES

DESCRIPTION

The LM3485 is a high efficiency PFET switching

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Easy to Use Control Methodology

regulator controller that can be used to quickly and

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No Control Loop Compensation Required

easily develop a small, low cost, switching buck

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4.5V to 35V Wide Input Range

regulator for a wide range of applications. The

hysteretic control architecture provides for simple

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design without any control loop stability concerns

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High Efficiency 93%

using a wide variety of external components. The

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±1.3% (±2% Over Temp) Internal Reference

PFET architecture also allows for low component

count as well as ultra-low dropout, 100% duty cycle

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100% Duty Cycle

operation. Another benefit is high efficiency operation

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Maximum Operating Frequency > 1MHz

at light loads without an increase in output ripple.

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Current Limit Protection

Current limit protection is provided by measuring the

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VSSOP-8

the need for a sense resistor. The cycle-by-cycle

APPLICATIONS

current limit can be adjusted with a single resistor,

ensuring safe operation over a range of output

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Set-Top Box

currents.

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DSL or Cable Modem

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PC/IA

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Auto PC

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TFT Monitor

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Battery Powered Portable Applications

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Distributed Power Systems

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Always On Power

Typical Application Circuit

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PRODUCTION DATA information is current as of publication date.

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Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

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