The LTC1698IGN is a precision secondary-side forward converter controller that synchronously drives external N-channel MOSFETs. It is designed for use with the LT3781 primary-side synchronous forward converter controller to create a completely isolated power supply. The LT3781 synchronizes the LTC1698IGN through a small pulse transformer and the LTC1698IGN 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.
The LTC1698IGN provides accurate secondary-side current limit using an external current sense resistor. The input voltage at the MARGIN pin provides ±5% output voltage adjustment. A power good flag and overvoltage input are provided to ensure proper power supply conditions. An auxiliary 3.3V logic supply is included that supplies up to 10mA of output current.
Feature
- 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
(Picture: Pinout)
