MP9989 CCM/DCM Flyback Ideal Diode SOIC

MP9989 CCM/DCM Flyback Ideal Diode SOIC

The MP9989 is a fast turn-off, intelligent rectifier for flyback converters that integrates a 100V MOSFET.

Key Specifications

Features

• Integrated 100V/10mΩ MOSFET
• Wide Output Range down to 0V
• No Need for Auxiliary Winding for High-Side or Low-Side Rectification
• Ringing Detection Prevents False Turn-On during DCM Operations
• Compatible with Energy Star
• 110µA Quiescent Current
• Supports DCM, CCM, and Quasi-Resonant Operations
• Available in SOIC-8 and QFN4x5-8 Packages

Typical Application Circuit

Applications

• Laptop Adapters
• QC and USB PD Charger

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