Datasheet

www.ti.com

Description

2.1 Applications

The UCC2891 is suited for use in isolated telecom 48-V input systems requiring high-efficiency and high-

power density for very low-output voltage, high-current converter applications, including:

• Server Systems

• Datacom

• Telecom

• DSP's, ASIC's, FPGA's

2.2 Features

The UCC2891EVM-520 features include:

• ZVS transformer reset using active-clamp technique in forward converter

• All surface mount components, double-sided half-brick (2.2 × 2.28 × 0.5) inches

• Complementary auxiliary drive for active clamp with programmable dead time for ZVS

• Current-mode control with synchronization function

• Internal PWM-slope compensation

• Start up directly from telecom input voltage

• Synchronous rectifier-output stage allows high-efficiency operation

• Programmable soft-start

• Up to 30-A dc-output current

• Regulation to zero-load current

• Non-latching output-current limiting

• Non-latching input-undervoltage protection

• 1500-V isolation primary to secondary

SLUU407A–June 2010–Revised May 2013 48-V to 3.3-V Forward Converter With Active-Clamp Reset Using the

UCC2891 Active-Clamp Current-Mode PWM Controller

Submit Documentation Feedback