UCC28230

UCC28230 UCC28231 www.ti.com ................................................................................................................................................... SLUS814A – FEBRUARY 2008 – REVISED JUNE 2008 Advanced PWM Controller for Bus Converters FEATURES 1 Programmable, Load Depended Off Time Control Frequency Controlled Start Up Allows Small Output Inductor, Low Ripple and Constant Current Start with Large Output Capacitor Two 0.2-A Push-Pull Outputs Provide Matched Control Signals D to External Drivers Two Additional 1- D Outputs for Optimal Use of Self-Driven or Control Driven Synchronous Rectifiers Unregulated, Fixed Volt-Second or Fixed Frequency Modes set by User Two, 1.5% Overall Accuracy Reference Voltage Options: 5-V for UCC28230 and 3.3-V for UCC28231 Resistor Programmable Switching Frequency up to 1 MHz Cycle-by-Cycle Current Limit Allows Parallel Operation with Droop Based Current Sharing Single External Capacitor sets Soft-Start and Over Current Hiccup Mode Parameters with Restart Severe Short Circuit Hiccup with Restart or Latch Off Protection Option by External Resistor Input Under Voltage Lock Out Thermal Shutdown Thermally Enhanced 3 mm × 2 mm SON-12 and TSSOP-14 Package Options APPLICATIONS Intermediate Bus Isolated Converters DC-to-DC Transformers DESCRIPTION The UCC28230, UCC28231 PWM bus controllers are optimized for use in high efficiency, high power density, unregulated intermediate bus converters. Top...