LTC3765 - Active Clamp Forward Controller and Gate Driver

Typical Application

Description

The LTC®3765 is a start-up controller and gate driver for use in a self-starting secondary-side control forward converter. When combined with the LTC3766 secondary-side synchronous forward controller, a complete isolated power supply is created using a minimum of discrete parts. A proprietary scheme is used to multiplex gate drive signals and bias power across the isolation barrier through a small pulse transformer. The LTC3765 contains an onchip bridge rectifier that extracts gate drive bias power from this pulse transformer, eliminating the need for a separate bias supply. A precision undervoltage lockout circuit and linear regulator controller ensure a quick and well-controlled start-up.

The LTC3765 includes an active clamp output for driving an external PMOS, as well as an adjustable delay to optimize efficiency. The active clamp architecture reduces voltage stress on the main power switch, and provides the highest possible efficiency. Overcurrent protection and the Direct Flux Limit guarantee no transformer saturation without compromising transient response.

People Who Viewed This Product Also Viewed

• LTC3766 - High Efficiency, Secondary-Side Synchronous Forward Controller
• LT3748 - 100V Isolated Flyback Controller
• LT3798 - Isolated No Opto-Coupler Flyback Controller with Active PFC
• LT3758 - High Input Voltage, Boost, Flyback, SEPIC and Inverting Controller
• LT4363 - High Voltage Surge Stopper with Current Limit
• LT3757 - Boost, Flyback, SEPIC and Inverting Controller
• LT8705 - 80V VIN and VOUT Synchronous 4-Switch Buck- Boost DC/DC Controller
• LT3752/LT3752-1 - Active Clamp Synchronous Forward Controllers with Internal Housekeeping Controller
• LTC4364 - Surge Stopper with Ideal Diode
• LT3796/LT3796-1 - 100V Constant-Current and Constant-Voltage Controller with Dual Current Sense