The FSFR-series are highly integrated power switches designed for high-efficiency half-bridge resonant converters. Offering everything necessary to build a reliable and robust resonant converter, the FSFR-series simplifies designs and improves productivity, while improving performance. The FSFR-series combines power MOSFETs with fast-recovery type body diodes, a high-side gate-drive circuit, an accurate current controlled oscillator, frequency limit circuit, soft-start, and built-in protection functions. The high-side gate-drive circuit has a common-mode noise cancellation capability, which guarantees stable operation with excellent noise immunity. The fast-recovery body diode of the MOSFETs improves reliability against abnormal operation conditions, while minimizing the effect of the reverse recovery. Using the zero-voltage-switching (ZVS) technique dramatically reduces the switching losses and significantly improves efficiency. The ZVS also reduces the switching noise noticeably, which allows a small-sized Electromagnetic Interference (EMI) filter.

The FSFR-series can be applied to various resonant converter topologies; such as series resonant, parallel resonant, and LLC resonant converters.

• Variable Frequency Control with 50% Duty Cycle for Half-Bridge Resonant Converter Topology
• High Efficiency through Zero Voltage Switching (ZVS)
• Internal SuperFET™s with Fast-Recovery Type Body Diode (t_rr=120ns) for FSFR2100 and UniFETs with Fast-Recovery Type Body Diode (t_rr<160ns) for FSFR2100U/2000/1900/1800/1700
• Fixed Dead Time (350ns) Optimized for MOSFETs
• Up to 300kHz Operating Frequency
• Pulse Skipping for Frequency Limit (Programmable) at Light-Load Condition
• Remote On/Off Control Using Control Pin
• Protection Functions: Over-Voltage Protection (OVP), Over-Load Protection (OLP), Over-Current Protection (OCP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD)

• PDP and LCD TVs
• Desktop PCs and Servers
• Adapters
• Telecom Power Supplies
• Audio Power Supplies