DESCRIPTION
The LT®1681 controller simplifies the design of high power synchronous dual transistor forward DC/DC converters. The part employs fixed frequency current mode control and supports both isolated and nonisolated topologies. The IC drives external N-channel power MOSFETs and operates with input voltages up to 72V.

FEATURES
■ High Voltage: Operation Up to 72V
■ Synchronizable Operating Frequency and Output Switch Phase for Multiple Controller Systems
■ Fixed Frequency Operation to 350kHz
■ Adaptive and Adjustable Blanking
■ Synchronous Rectifier Driver
■ Local 1% Voltage Reference
■ Undervoltage Lockout Protection with Hysteresis
■ Input Overvoltage Protection
■ Programmable Start Inhibit
■ Transformer Primary Saturation Protection
■ Optocoupler Feedback Support
■ Soft-Start Control

APPLICATIONS
■ Isolated Telecommunication Systems
■ Personal Computers and Peripherals
■ Lead Acid Battery Backup Systems
■ Automotive and Heavy Equipment