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

Turn-on into Prebiased Loads

• Synchronous Rectifiers Disabled in UVLO Mode

and Hiccup Mode

• Two Independent, Programmable Dead-Time

Adjustments to Enable Zero-Volt Switching

• Four High-Current 2-A Bridge Gate Drivers

• Wide-Bandwidth Opto-Coupler 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/Electronic Warfare

• Power: Telecom DC/DC Module: Analog

• Private Branch Exchange (PBX)

• Solar Power Inverters

• Vector Signal Generator

• Microwave Oven

• Point-to-Point Microwave Backhaul

• Power: Telecom/Server AC/DC Supply: Dual

Controller: Analog

• Solar Micro-Inverter

• TETRA Base Station

• Washing Machine: Low-End

3 Description

The LM5046 PWM controller contains all of the

features necessary to implement a phase-shifted fullbridge

topology power converter 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- and low-side gate drivers for the four external bridge MOSFETs, plus control signals for the

secondary-side synchronous rectifier MOSFETs.

External resistors program the dead-time to enable

zero-volt switching of the primary FETs. Intelligent

startup of 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.