PVIN

SW

AGND

FB

PGOOD

EN

SS/TRK

AVIN

COMP

LM20146

L

VCC

PGND

RT

(optional)

LM20146

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SNVS563C – FEBRUARY 2008 – REVISED APRIL 2013

LM20146 6A, Adjustable Frequency Synchronous Buck Regulator

Check for Samples: LM20146

1

FEATURES

DESCRIPTION

The LM20146 is a full featured adjustable frequency

2

•

Input Voltage Range 2.95V to 5.5V

synchronous buck regulator capable of delivering up

•

Accurate Current Limit Minimizes Inductor

to 6A of continuous output current. The current mode

Size

control loop can be compensated to be stable with

•

97% Peak Efficiency

virtually any type of output capacitor. For most cases,

compensating the device only requires two external

•

Adjustable Switching Frequency (250 kHz to

components, providing maximum flexibility and ease

750 kHz)

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

•

16m

Ω and 20mΩ Integrated FET Switches

voltage range of 2.95V to 5.5V making it suitable for

•

Starts up into Pre-biased Loads

a wide variety of low voltage systems.

•

Output Voltage Tracking

The device features internal over voltage protection

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

•

Peak Current Mode Control

increased system reliability. A precision enable pin

•

Adjustable Output Voltage Down to 0.8V

and integrated UVLO allows the turn-on of the device

•

Adjustable Soft-Start with External Capacitor

to be tightly controlled and sequenced. Start-up

•

Precision Enable Pin with Hysteresis

inrush currents are limited by both an internally fixed

and externally adjustable Soft-Start circuit. Fault

•

Integrated OVP, UVLO, Power Good and

detection and supply sequencing are possible with

Thermal Shutdown

the integrated power good circuit.

•

16-Pin HTSSOP Exposed Pad Package

The LM20146 is designed to work well in multi-rail

power supply architectures. The output voltage of the

APPLICATIONS

device can be configured to track a higher voltage rail

•

Simple to Design, High Efficiency Point of

using the SS/TRK pin. If the output of the LM20146 is

Load Regulation from a 5V or 3.3V Bus

pre-biased at startup it will not pull the ouput low.

•

High Performance DSPs, FPGAs, ASICs and

The frequency of this device can be adjusted from

Microprocessors

250 kHz to 750 kHz by connecting an external

resistor from the RT pin to ground.

•

Broadband, Networking and Optical

Communications Infrastructure

The LM20146 is offered in a 16-pin HTSSOP

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 © 2008–2013, 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.