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This literature is subject to all applicable copyright laws and is not for resale in any manner.FAN7621 PFM Controller for Half-Bridge Resonant Converters July 2010 FAN7621 PFM Controller for Half-Bridge Resonant Converters Features Description The FAN7621 is a pulse frequency modulation controller Variable Frequency Control with 50% Duty Cycle for high-efficiency half-bridge resonant converters. for Half-bridge Resonant Converter Topology Offering everything necessary to build a reliable and High Efficiency through Zero Voltage Switching (ZVS) robust resonant converter, the FAN7621 simplifies Fixed Dead Time (350ns) designs and improves productivity, while improving performance. The FAN7621 includes a high-side gate- Up to 300kHz Operating Frequency drive circuit, an accurate current controlled oscillator, Pulse Skipping for Frequency Limit (Programmable) frequency limit circuit, soft-start, and built-in protection at Light-Load Condition functions. The high-side gate-drive circuit has a Remote On/Off Control Using CON Pin 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 FAN7621 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 Part Number Package Packaging Method Temperature FAN7621N 16-Lead, Dual Inline Package (DIP) Tube FAN7621SJ 16-Lead, Small-Outline Package (SOP) Tube -40 C ~ 130 C FAN7621SJX 16-Lead, Small-Outline Package (SOP) Tape & Reel 2009 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN7621 Rev. 1.0.3