The FSDH565RN is a highly integrated power switch from Fairchild Semiconductor (now ON Semiconductor) designed for offline flyback converters. It incorporates a SenseFET and a current mode PWM controller, offering a cost-effective and simplified solution for power supply designs. The integrated features help reduce external component count and improve overall system efficiency and reliability.

Applications:

• Power adapters for mobile devices and peripherals
• Auxiliary power supplies in home appliances
• Standby power supplies for consumer electronics
• Open-frame power supplies
• Battery chargers

Features:

• Integrated SenseFET and PWM controller
• Low startup current
• Built-in soft-start function
• Frequency hopping for improved EMI performance
• Pulse-by-pulse current limiting
• Overvoltage protection (OVP)
• Overload protection (OLP)
• Thermal shutdown function (TSD)
• Under-voltage lockout (UVLO)

Benefits:

• Reduced component count simplifies design and lowers BOM cost
• Improved efficiency due to integrated design
• Enhanced reliability with built-in protection features
• Lower EMI emissions due to frequency hopping
• Robust performance under various operating conditions
• Simplified PCB layout
• Faster time to market

Additional Details:

The FSDH565RN operates in current mode PWM, providing inherent line voltage feed-forward for improved regulation. The integrated SenseFET offers excellent avalanche ruggedness, ensuring reliable operation even under transient conditions. The soft-start function minimizes stress on the power components during startup, further enhancing reliability. The frequency hopping feature reduces EMI emissions, simplifying compliance with regulatory requirements. It's typically packaged in a DIP or SMD package for easy integration into various power supply designs.

This power switch is designed to meet stringent energy efficiency requirements and safety standards. It is a suitable choice for applications where compact size, high efficiency, and robust protection are essential. The integrated protection features safeguard the power supply from damage due to overvoltage, overload, and thermal events.