Texas Instruments UCC2891 Benutzerhandbuch
www.ti.com
2.1
Applications
2.2
Features
Description
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:
high-power density for very low-output voltage, high-current converter applications, including:
•
Server Systems
•
Datacom
•
Telecom
•
DSP's, ASIC's, FPGA's
The UCC2891EVM 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 auxilliary 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 overcurrent and short circuit protection
•
Non-latching, Input undervoltage protection
•
1500-V isolation primary to secondary
Using the UCC2891 Active Clamp Current Mode PWM Controller
4
SLUU178A – November 2003 – Revised December 2006