HF500-15 Fixed Frequency Multi-Mode Flyback Regulator Integrated SOIC8

HF500-15 Fixed Frequency Multi-Mode Flyback Regulator Integrated SOIC8

The HF500-15 is a fixed-frequency, current- mode regulator with built-in slope compensation.

Key Specifications

Features

• 700V/4.5 Integrated MOSFET with high single pulse avalanche energy
• Fixed-Frequency Current-Mode-Control Operation with Built-In Slope Compensation
• Frequency Foldback Down to fOSC(min) at Light Load
• Burst Mode for Low Standby Power Consumption
• Frequency Jittering for a Reduced EMI Signature
• Over-Power Compensation
• Internal High-Voltage Current Source
• VCC Under-Voltage Lockout (UVLO) with Hysteresis
• Programmable Input B/O and OVP
• Overload Protection (OLP) with a Programmable Delay

Typical Application Circuit

Applications

• Power Supplies for Home Appliances
• Set-Top Boxes
• Standby and Auxiliary Power

Design Notes

• The PFC inductor must support the maximum duty cycle at the lowest line voltage, which is where saturation risk peaks.
• High-voltage startup and X-capacitor discharge paths dominate no-load standby loss; verify them against the efficiency target.
• Leakage inductance and the RCD clamp set the turn-off loss — snubber values are a thermal trade-off, not a fixed recipe.
• Synchronous rectification timing must track the primary switching; a mistimed SR FET conducts through its body diode and fails hot.

Common Questions