LYT4221E

AC DC Converters, Offline Switchers Overview

The LYT4221E is a high-performance, single-stage LED driver IC from the LYTSwitch-4 family by Power Integrations. It integrates a primary-side constant current controller and power switch to deliver precise regulation without optoisolators. Designed for universal AC input (85–265 VAC), it supports TRIAC dimming and non-dimming applications. The device achieves high power factor (>0.9) and low total harmonic distortion (<10%), meeting EN61000-3-2 standards. It utilizes a 132 kHz switching frequency to minimize magnetic component size and eliminates primary-side aluminum electrolytic capacitors for extended lifetime.

AC DC Converters, Offline Switchers Feature Summary

• Integrates primary-side constant current control and power switch to eliminate optoisolators and reduce component count.
• Provides better than ±5% constant current regulation accuracy for stable LED performance.
• Supports leading-edge and trailing-edge TRIAC dimming with fast start-up and wide dimming range.
• Eliminates primary-side bulk aluminum electrolytic capacitors to ensure long operational lifetime in high-temperature environments.

AC DC Converters, Offline Switchers Applications

• High-power LED lighting fixtures requiring high power factor correction.
• TRIAC dimmable LED bulbs and downlights.
• Non-dimmable general illumination LED drivers.
• Applications requiring compliance with EN61000-3-2 harmonic standards.

AC DC Converters, Offline Switchers Procurement Notes

Verify availability status as the LYT4221E may be discontinued or subject to end-of-life notices. Confirm package type eSIP-7C-6 compatibility with your PCB layout. Check for moisture sensitivity levels if storage conditions exceed manufacturer recommendations. Validate that the specific suffix matches your design requirements. Consult official distributors for last-time buy information if applicable.

AC DC Converters, Offline Switchers Selection Notes

Select this component for designs prioritizing high efficiency and reduced bill of materials through integration. Ensure the application requires primary-side regulation capabilities. Verify that the target output power aligns with the specific variant's rating within the LYTSwitch-4 family. Consider thermal management needs given the integrated switch. Confirm compatibility with existing TRIAC dimmers if dimming functionality is required.

AC DC Converters, Offline Switchers Part Context

The LYT4221E belongs to the LYTSwitch-4 family, which combines PFC and constant current functions into a single stage. This architecture simplifies design and improves reliability compared to multi-stage solutions. The family is known for enabling cost-effective, high-reliability LED drivers suitable for global markets with varying input voltage ranges.

AC DC Converters, Offline Switchers Replacement Considerations

Official documentation suggests the LYTSwitch-6 family as a suggested alternative for new designs. Verify pinout and electrical parameter compatibility before substitution. Review updated feature sets and efficiency improvements in newer generations. Ensure the replacement meets all original regulatory and performance requirements.