LM25011, LM25011-Q1

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SNVS617F – MAY 2009 – REVISED JANUARY 2011

LM25011, LM25011Q, LM25011A, LM25011AQ

42V 2A Constant On-Time Switching Regulator With Adjustable Current Limit

Check for Samples: LM25011, LM25011-Q1

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FEATURES

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LM25011Q is an Automotive Grade product

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COT topology features:

that is AEC-Q100 grade 1 qualified (-40°C to

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Switching frequency remains nearly

+125°C operating junction temperature)

constant with load current and input

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LM25011A allows low dropout operation at

voltage variations

high switching frequency

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Ultra-fast transient response

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Input operating voltage range: 6V to 42V

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No loop compensation required

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Absolute maximum input rating: 45V

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Stable operation with ceramic output

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Integrated 2A N-Channel Buck Switch

capacitors

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Adjustable current limit allows for smaller

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Allows for smaller output capacitor and

inductor

current sense resistor

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Adjustable output voltage from 2.51V

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Adjustable Soft-Start timing

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Thermal shutdown

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Power Good output

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Precision 2% feedback reference

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Switching frequency adjustable to 2 MHz

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Package

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MSOP-10EP

DESCRIPTION

The LM25011 Constant On-time Step-Down Switching Regulator features all the functions needed to implement

a low cost, efficient, buck bias regulator capable of supplying up to 2A of load current. This high voltage regulator

contains an N-Channel Buck switch, a startup regulator, current limit detection, and internal ripple control. The

constant on-time regulation principle requires no loop compensation, results in fast load transient response, and

simplifies circuit implementation. The operating frequency remains constant with line and load. The adjustable

valley current limit detection results in a smooth transition from constant voltage to constant current mode when

current limit is reached, without the use of current limit foldback. The PGD output indicates the output voltage

has increased to within 5% of the expected regulation value. Additional features include: Low output ripple, VIN

under-voltage lock-out, adjustable soft-start timing, thermal shutdown, gate drive pre-charge, gate drive under-

voltage lock-out, and maximum duty cycle limit.

The LM25011A has a shorter minimum off-time than the LM25011, which allows for higher frequency operation

at low input voltages.

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2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2009–2011, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.