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This literature is subject to all applicable copyright laws and is not for resale in any manner.FAN7621B PFM Controller for Half-Bridge Resonant Converters July 2010 FAN7621B PFM Controller for Half-Bridge Resonant Converters Features Description The FAN7621B is a pulse frequency modulation Variable Frequency Control with 50% Duty Cycle controller for high-efficiency half-bridge resonant for Half-bridge Resonant Converter Topology converters. Offering everything necessary to build a High Efficiency through Zero Voltage Switching (ZVS) reliable and robust resonant converter, the FAN7621B Fixed Dead Time (350ns) simplifies designs and improves productivity, while improving performance. The FAN7621B includes a high- Up to 300kHz Operating Frequency side gate-drive circuit, an accurate current controlled Pulse Skipping for Frequency Limit (Programmable) oscillator, frequency limit circuit, soft-start, and built-in at Light-Load Condition protection functions. The high-side gate-drive circuit has Remote On/Off Control using CON Pin a common-mode noise cancellation capability, which Protection Functions: Over-Voltage Protection guarantees stable operation with excellent noise immunity. Using the zero-voltage-switching (ZVS) (OVP), Overload Protection (OLP), Over-Current technique dramatically reduces the switching losses and Protection (OCP), Abnormal Over-Current Protection efficiency is significantly improved. The ZVS also (AOCP), Internal Thermal Shutdown (TSD) reduces the switching noise noticeably, which allows a small-sized Electromagnetic Interference (EMI) filter. Applications The FAN7621B can be applied to various resonant converter topologies such as series resonant, parallel PDP and LCD TVs resonant, and LLC resonant converters. Desktop PCs and Servers Adapters Telecom Power Supplies Related Resources Video Game Consoles AN4151 Half-bridge LLC Resonant Converter Design TM using FSFR-series Fairchild Power Switch (FPS ) Ordering Information Operating Junction Packaging Part Number Package Temperature Method FAN7621BSJ Tube -40 C ~ 130 C 16-Lead Small Outline Package (SOP) FAN7621BSJX Tape & Reel 2009 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN7621B Rev. 1.0.1