PVIN

SW

AGND

FB

PGOOD

EN

SS/TRK

AVIN

COMP

LM20143

L

VCC

PGND

RT

(optional)

LM20143

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SNVS528F – OCTOBER 2007 – REVISED NOVEMBER 2011

Check for Samples: LM20143

1

FEATURES

DESCRIPTION

2

•

Available in AEC-Q100 Temperature Grade 1

The LM20143 is a full featured adjustable frequency

•

Input voltage range: 2.95V to 5.50V

synchronous buck regulator capable of delivering up

•

Accurate current limit minimizes inductor size

to 3A of continuous output current. The current mode

control loop can be compensated to be stable with

•

97% peak efficiency

virtually any type of output capacitor. For most cases,

•

Adjustable output voltage down to 0.80V

compensating the device only requires two external

•

Adjustable switching frequency (500 kHz to 1.5

components, providing maximum flexibility and ease

MHz)

of use. The device is optimized to work over the input

voltage range of 2.95V to 5.5V making it suited for a

•

32 m

Ω integrated FET switches

wide variety of low voltage systems.

•

Starts into prebiased loads

The device features internal over voltage protection

•

Output voltage tracking

(OVP) and over current protection (OCP) circuits for

•

Peak current mode control

increased system reliability. A precision enable pin

•

Adjustable Soft-Start with external capacitor

and integrated UVLO allows the turn-on of the device

to be tightly controlled and sequenced. Start-up

•

Precision enable pin with hysteresis

inrush currents are limited by both an internally fixed

•

Integrated OVP, UVLO, power good and

and externally adjustable Soft-Start circuit. Fault

thermal shutdown

detection and supply sequencing is possible with the

•

TSSOP 16-pin exposed pad package

integrated power good circuit.

The frequency of this device can be adjusted from

APPLICATIONS

500 kHz to 1.5 MHz by connecting an external

•

Simple to design, high efficiency point of load

resistor from the RT pin to ground.

regulation from a 5V or 3.3V bus

The LM20143 is designed to work well in multi-rail

•

High Performance DSPs, FPGAs, ASICs and

power supply architectures. The output voltage of the

microprocessors

device can be configured to track a higher voltage rail

using the SS/TRK pin. If the output of the LM20143 is

•

Broadband, Networking and Optical

pre-biased at startup it will not sink current to pull the

Communications Infrastructure

output low until the internal soft-start ramp exceeds

the voltage at the feedback pin.

The LM20143 is offered in a 16-pin TSSOP package

with an exposed pad that can be soldered to the

PCB, eliminating the need for bulky heatsinks.

Typical Application Circuit

1

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Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2

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PRODUCTION DATA information is current as of publication date.

Copyright © 2007–2011, 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.