NCP4305QDR2G

Power Supply Controllers, Monitors Overview

The NCP4305QDR2G is a secondary side synchronous rectification driver designed for high-efficiency switch-mode power supplies. It controls SR MOSFETs in DCM/CCM flyback, quasi-resonant flyback, forward, and half-bridge resonant LLC topologies. Key electrical parameters include a maximum Vcc of 35V, typical reference voltage of 8.9V, and maximum ICC of 7.5E-4A. Operating temperature range is -40°C to 125°C. The device features externally adjustable minimum off-time and on-time blanking periods to mitigate ringing from PCB layout parasitics.

Power Supply Controllers, Monitors Feature Summary

• Self-synchronization feature ensures reliable and noiseless operation of the synchronous rectification system.
• Utilizes Kelvin connection of the driver to the MOSFET to achieve high efficiency at full load.
• Incorporates light load detection architecture to maintain high efficiency under light load conditions.
• Precise turn-off threshold and extremely low turn-off delay time maximize synchronous rectification MOSFET conduction time.

Power Supply Controllers, Monitors Applications

• DCM or CCM flyback converters
• Quasi-resonant flyback topologies
• Forward converter designs
• Half-bridge resonant LLC converters

Power Supply Controllers, Monitors Procurement Notes

Verify component authenticity through authorized channels as the part may be subject to supply constraints. Confirm package integrity and moisture sensitivity level handling requirements prior to assembly. Cross-reference datasheet revisions to ensure compatibility with current design specifications. Validate that the SOIC-8 package variant matches the intended PCB footprint and thermal management strategy.

Power Supply Controllers, Monitors Selection Notes

Select this driver for applications requiring precise timing control to minimize switching losses in synchronous rectification stages. The external adjustability of blanking periods allows optimization for specific PCB layouts and parasitic characteristics. Ensure the target topology supports the self-synchronization mechanism for optimal performance across varying load conditions.

Power Supply Controllers, Monitors Part Context

The NCP4305 belongs to onsemi's secondary side controller family, specifically tailored for synchronous rectification in AC/DC adapters and DC/DC converters. It replaces traditional rectification diodes to improve overall system efficiency. The QDR2G suffix indicates the SOIC-8 package and tape-and-reel packaging configuration.

Power Supply Controllers, Monitors Replacement Considerations

NCP4305DDR2G: Pin-compatible alternative in SOIC-8 package.