Vout

T1

T1

Vin

ISOLATED

FEEDBACK

SSOFF

VCC

REF

AGND

PGND

SS

RES

RT

UVLO

VIN

HO1

BST1 HS1 LO1

CS

LO2

HS2 BST2 HO2

COMP

LM5045 FULL-BRIDGE CONTROLLER

WITH INTEGRATED GATE DRIVERS

RD1

RD2

GATE

DRIVE

ISOLATION

SR1

SR2

VCC

VCC

ISOLATION

BOUNDARY

SLOPE RAMP

SSSR

OVP

LM5045

www.ti.com

SNVS699G – FEBRUARY 2011 – REVISED MARCH 2013

Full-Bridge PWM Controller with Integrated MOSFET Drivers

Check for Samples: LM5045

1

FEATURES

DESCRIPTION

The LM5045 PWM controller contains all of the

2

•

Highest Integration Controller for Small Form

features necessary to implement Full-Bridge topology

Factor, High Density Power Converters

power converters using either current mode or

•

High Voltage Start-up Regulator

voltage mode control. This device is intended to

•

Intelligent Sync Rectifier Start-up Allows

operate on the primary side of an isolated dc-dc

converter with input voltage up to 100V. This highly

Linear Turn-on into Pre-biased Loads

integrated controller-driver provides dual 2A high and

•

Synchronous Rectifiers Disabled in UVLO

low side gate drivers for the four external brige

mode and Hiccup Mode

MOSFETs plus control signals for the secondary side

•

Two Independent, Programmable

synchronous rectifier MOSFETs. External resistors

Synchronous Rectifier dead-time Adjustments

program the leading and trailing edge dead-time

between the main and synchronous rectifier control

•

Four High Current 2A Bridge Gate Drivers

signals.

Intelligent

startup

of

the

synchronous

•

Wide-Bandwidth Opto-coupler Interface

rectifiers allows monotonic turn-on of the power

•

Configurable for either Current Mode or

converter

even

with

pre-bias

load

conditions.

Voltage Mode Control

Additional features include cycle-by-cycle current

limiting, hiccup mode restart, programmable soft-

•

Dual-mode Over-Current Protection

start, synchronous rectifier soft-start and a 2 MHz

•

Resistor Programmed 2MHz Oscillator

capable oscillator with synchronization capability and

•

Programmable Line UVLO and OVP

thermal shutdown.

PACKAGES

•

HTSSOP 28 pin

•

WQFN 28 pin (5mm x 5mm)

Simplified Full-Bridge Power Converter

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

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

2

All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Copyright © 2011–2013, 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.