LTC3725

U U FEATURES ■ High Speed Gate Driver for Forward Converter ■ On-Chip Rectifier and Self-Starting Architecture Eliminates Need for Separate Gate Drive Bias Supply ■ Wide Input Voltage Supply Range: 9V and Up ■ Linear Regulator Controller for Fast Start-Up ■ Precision UVLO with Adjustable Hysteresis ■ Overcurrent Protection ■ Volt-Second Limit Prevents Transformer Core Saturation ■ Voltage Feedforward for Fast Transient Response ■ Available in 10-Lead MSOP Package U APPLICATIO S ■ Isolated 48V Telecommunication Systems ■ Internet Servers and Routers ■ Distributed Power Step-Down Converters ■ Automotive and Heavy Equipment LTC3725 Single-Switch Forward Controller and Gate Driver DESCRIPTIO The LTC®3725 is a controller for a single-switch forward converter and includes an on-chip gate driver. For secondary-side control, combine the LTC3725 with the LTC3706 PolyPhase® secondary-side synchronous forward controller to create a complete forward converter using a minimum of discrete parts. A proprietary scheme is used to multiplex gate drive signals across the isolation barrier through a tiny pulse transformer. The on-chip rectifier and the same pulse transformer provide gate drive bias power. Alternatively, the LTC3725 can be used as a standalone voltage mode controller in a primary-side control architecture with optoisolator feedback. Voltage feedforward provides excellent line regulation and transient response. , LT, LTC and LTM are registered trademarks of Linear Technology Cor...