Features

• Direct Flux Limit™ Guarantees No Saturation
• Fast and Accurate Average Current Limit
• Clean Start-Up Into Pre-Biased Output
• Secondary-Side Control for Fast Transient Response
• Simple, Self-Starting Architecture
• Synchronous MOSFET Reverse Current Limit
• PolyPhase® Operation Eases High-Power Design
• True Remote Sense Differential Amplifier
• Remote Sense Reverse Protection
• High Voltage Linear Regulator Controller
• Internal LDO Powers Gate Drive from V_OUT
• Overtemperature/Overvoltage Protection
• Low Profile 4mm × 5mm QFN and Narrow 28-Lead SSOP Packages

Typical Application

Description

The LTC®3766 is a PolyPhase-capable secondary-side controller for synchronous forward converters. When used in conjunction with the LTC3765 active-clamp forward controller and gate driver, the part creates a complete isolated power supply that combines the power of multiphase operation with the speed of secondary-side control.

The LTC3766 has been designed to simplify the design of active clamp forward converters. Working in concert with the LTC3765, the LTC3766 forms a robust, self-starting converter that eliminates the need for the separate bias regulator that is commonly used in secondary-side control applications. A precision current-limit coupled with clean start-up into a pre-biased load make the LTC3766 an excellent choice for high-power battery charger applications.

The LTC3766 provides extensive remote sensing and output protection features, while Direct Flux Limit guarantees no transformer saturation without compromising transient response. A linear regulator controller and internal bypass LDO are also provided to simplify the generation of the secondary-side bias voltage.