DESCRIPTION
The LTC®1698 is a precision secondary-side forward converter controller that synchronously drives external N-channel MOSFETs. It is designed for use with the LT®3781 primary-side synchronous forward converter controller to create a completely isolated power supply. The LT3781 synchronizes the LTC1698 through a small pulse transformer and the LTC1698 drives a feedback optocoupler to close the feedback loop. Output accuracy of ±0.8% and high efficiency over a wide range of load currents are obtained.

FEATURES
■ High Efficiency Over Wide Load Current Range
■ ±0.8% Output Voltage Accuracy
■ Dual N-Channel MOSFET Synchronous Drivers
■ Pulse Transformer Synchronization
■ Optocoupler Feedback Driver
■ Programmable Current Limit Protection
■ ±5% Margin Output Voltage Adjustment
■ Adjustable Overvoltage Fault Protection
■ Power Good Flag
■ Auxiliary 3.3V Logic Supply
■ Available in 16-Lead SSOP and SO Packages

APPLICATIONS
■ 48V Input Isolated DC/DC Converters
■ Isolated Telecommunication Power Systems
■ Distributed Power Step-Down Converters
■ Industrial Control Systems
■ Automotive and Heavy Equipment