LM5045 Full Bridge PWM Controller With Integrated MOSFET Drivers LM5045 SNVS699H FEBRUARY 2011 REVISED JANUARY 2015 3 Description The LM5045 PWM controller contains all of the features necessary to implement full bridge topology power converters using either current mode or voltage mode control This device is intended to operate on the primary side of an isolated DC DC converter with input voltage up to 100 V This highly integrated controller driver provides dual 2 A high side and low side gate drivers for the four external bridge MOSFETs plus the secondary side synchronous rectifier MOSFETs External resistors program the leading and trailing edge dead time between the main and synchronous rectifier control signals the synchronous rectifiers allows monotonic turnon of the power converter even with prebias load conditions Additional features include cycle by cycle current limiting hiccup mode restart programmable soft start synchronous rectifier soft start and a 2 MHz capable oscillator with synchronization capability and thermal shutdown Intelligent start up of signals control for Device Information 1 LM5045 PART NUMBER BODY SIZE NOM 9 70 mm 4 40 mm 5 00 mm 5 00 mm 1 For all available packages see the orderable addendum at PACKAGE HTSSOP 28 WQFN 28 the end of the data sheet 1 Features 1 Highest Integration Controller for Small Form Factor High Density Power Converters High Voltage Start Up Regulator Intelligent Sync Rectifier Start Up Allows Linear Turnon Into Prebiased Loads Synchronous Rectifiers Disabled in UVLO mode and Hiccup Mode Two Independent Programmable Synchronous Rectifier Dead Time Adjustments Four High Current 2 A Bridge Gate Drivers Wide Bandwidth Optocoupler Interface Configurable for Either Current Mode or Voltage Mode Control Dual Mode Overcurrent Protection Resistor Programmed 2 MHz Oscillator Programmable Line UVLO and OVP 2 Applications E Bike Military Radar and Electronic Warfare Power Telecom DC DC Module Analog Private Branch Exchange PBX Solar Power Inverters Vector Signal Generators Microwave Ovens Point to Point Microwave Backhaul Power Telecom Server AC DC Supply Dual Controller Analog Solar Micro Inverters TETRA Base Stations Washing Machine Low End Simplified Full Bridge Power Converter 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability warranty changes use in safety critical applications intellectual property matters and other important disclaimers PRODUCTION DATA VoutT1T1VinISOLATED FEEDBACK SSOFFVCCREFAGNDPGNDSSRESRTUVLOVINHO1BST1HS1LO1CSLO2HS2BST2HO2COMPLM5045 FULL BRIDGE CONTROLLERWITH INTEGRATED GATE DRIVERSRD1RD2GATEDRIVEISOLATIONSR1SR2VCCVCCISOLATION BOUNDARYSLOPERAMPSSSROVPProductFolderSample BuyTechnicalDocumentsTools SoftwareSupport Community LM5045 SNVS699H FEBRUARY 2011 REVISED JANUARY 2015 www ti com Table of Contents 1 Features 1 2 Applications 1 3 Description 1 4 Revision History 2 5 Pin Configuration and Functions 3 6 Specifications 6 6 1 Absolute Maximum Ratings 6 6 2 ESD Ratings 6 6 3 Recommended Operating Conditions 6 6 4 Thermal Information 6 6 5 Electrical Characteristics 7 6 6 Typical Characteristics 10 7 Detailed Description 12 7 1 Overview 12 7 2 Functional Block Diagram 13 7 3 Feature Description 14 7 4 Device Functional Modes 22 8 Application and Implementation 25 8 1 Application Information 25 8 2 Typical Application 25 9 Power Supply Recommendations 34 10 Layout 34 10 1 Layout Guidelines 34 10 2 Layout Example 35 11 Device and Documentation Support 37 11 1 Trademarks 37 11 2 Electrostatic Discharge Caution 37 11 3 Glossary 37 12 Mechanical Packaging and Orderable Information 37 4 Revision History NOTE Page numbers for previous revisions may differ from page numbers in the current version Changes from Revision G March 2013 to Revision H Added Pin Configuration and Functions section ESD Ratings table Feature Description section Device Functional Modes Application and Implementation section Power Supply Recommendations section Layout section Device and Documentation Support section and Mechanical Packaging and Orderable Information section 1 Changes from Revision F March 2013 to Revision G Changed layout of National Data Sheet to TI format 25 Page Page 2 Submit Documentation Feedback Copyright 2011 2015 Texas Instruments Incorporated Product Folder Links LM5045 www ti com 5 Pin Configuration and Functions LM5045 SNVS699H FEBRUARY 2011 REVISED JANUARY 2015 28 Pin HTSSOP With PowerPAD PWP Package Top View RSG Package 28 Pin WQFN 5 mm 5 mm Top View Copyright 2011 2015 Texas Instruments Incorporated Submit Documentation Feedback 3 Product Folder Links LM5045 SSRESHS2HO2BST2SSSRREFRTSLOPERD2COMPAGNDRD1PGNDLO1VCCLO2BST1SS OFFSR1OVPRAMPUVLOCSHS1HO1VINSR212345672120191817161589101112131428272625242322VINPGNDLO1VCCLO2SR2SR1HS2HO2BST2HS1BST1HO1COMPRD2UVLOOVPCSRAMPSSSRAGNDSLOPERTREFRD1SSSS OFFRES46532178910111213142019181716152625242322212827PowerPAD LM5045 SNVS699H FEBRUARY 2011 REVISED JANUARY 2015 PIN HTSSOP WQFN I O O NAME AGND BST1 BST2 COMP CS HO1 HO2 HS1 HS2 LO1 LO2 OVP OTP PGND RAMP RD1 RD2 REF RES RT SYNC SLOPE 9 25 18 6 4 26 17 27 16 23 20 2 22 3 10 11 7 12 8 5 5 21 14 2 28 22 13 23 12 19 16 26 18 27 6 7 3 8 4 1 Pin Functions DESCRIPTION APPLICATION INFORMATION www ti com Analog Ground Gate Drive Bootstrap Input to the Pulse Width Modulator Current Sense Input O High Side Output Driver Switch Node O Low Side Output Driver Overvoltage Protection O Power Ground Connect directly to the Power Ground Bootstrap capacitors connected between BST1 2 and SW1 2 provide bias supply for the high side HO1 2 gate drivers External diodes are required between VCC and BST1 2 to charge the bootstrap capacitors when SW1 2 are low An external opto coupler connected to the COMP pin sources current into an internal NPN current mirror The PWM duty cycle is at maximum with zero input current while 1 mA reduces the duty cycle to zero The current mirror improves the frequency response by reducing the AC voltage across the opto coupler If CS exceeds 750 mV the PWM output pulse will be terminated entering cycle by cycle current limit An internal switch holds CS low for 40 nS after either output switches high to blank leading edge transients High side PWM outputs capable of driving the upper MOSFET of the bridge with 1 5 A peak source and 2 A peak sink current Common connection of the high side FET source low side FET drain and transformer primary winding Alternating output of the PWM gate driver Capable of 1 5 A peak source and