FSFR1800XS: Integrated Power Switch (FPS™) for 260W Half-Bridge Resonant Converter

The FSFR-XS series includes 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-XS series simplifies designs while improving productivity and performance. The FSFR-XS 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 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 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-XS series can be applied to resonant converter topologies such as series resonant, parallel resonant, and LLC resonant converters.

Features

• Variable Frequency Control with 50% Duty Cycle for Half-Bridge Resonant Converter Topology
• High Efficiency through Zero Voltage Switching (ZVS)
• Internal UniFET™s with Fast-Recovery Body Diode
• Fixed Dead Time (350ns) Optimized for MOSFETs
• Up to 300kHz Operating Frequency
• Auto-Restart Operation for All Protections with An External LV_CC
• Protection Functions: Over-Voltage Protection (OVP), Over-Current Protection (OCP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD)

Application Notes