FAN4801MY

Overview

The FAN4801MY is a discontinued Power Factor Correction (PFC) and Pulse Width Modulation (PWM) controller combination designed for power supplies incorporating boost PFC stages. It operates in Continuous Conduction Mode (CCM) with a typical switching frequency of 64 kHz. The device supports both current-mode and voltage-mode PWM operation, featuring an accurate 49.9% maximum PWM duty cycle to extend operational life. It includes integrated under-voltage protection and PFC soft-start functions absent in earlier ML4800 models. The component utilizes a 16-pin SOIC package with a supply voltage range of 11V to 22V and a maximum operating temperature of 105°C.

Feature Summary

• Integrated dual-controller architecture combining CCM PFC and PWM regulation in a single package
• Supports flexible PWM control modes including current-mode and voltage-mode operation
• Includes built-in under-voltage protection and dedicated PFC soft-start functionality
• Features low operating current to reduce external component power dissipation

Applications

• Power supplies utilizing boost PFC topology
• Systems requiring combined power factor correction and post-regulation
• Universal input AC-DC conversion designs

Procurement Notes

Verify the obsolete status before procurement as the component is marked Not Recommended for New Designs. Confirm that existing inventory sources are legitimate distributors. Ensure design modifications account for the specific pin configurations and electrical characteristics documented in the official datasheet rather than relying on generic family assumptions.

Selection Notes

Select this component only for maintenance or replacement of legacy systems using ML4800 or FAN4800. Designers must adjust external components, specifically increasing RAC resistance and modifying RT/CT values to achieve the specified 64 kHz frequency. Verify that the circuit accommodates the reduced soft-start current compared to previous generations.

Part Context

This part belongs to the FAN4800A/C and FAN4801 series, which are enhanced versions of the ML4800 and FAN4800 controllers. The series offers improved efficiency through lower operating currents and added protection features like UVLO. The FAN4801MY specifically denotes the surface-mount SOIC-16 variant manufactured by Fairchild Semiconductor, now part of onsemi.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. The component is explicitly marked as Not Recommended for New Designs.