LYT4211E2 [Power Integrations]

The LYTSwitch-4 family integrates a controller and high-voltage power FET into a single package, providing high power factor (>0.9) and constant current output with better than ±5% regulation in a single-stage design. Features include up to 92% efficiency, 132 kHz switching frequency for small magnetics, fast start-up (<250 ms at full brightness), and support for leading/trailing-edge TRIAC dimming. The primary-side control technique eliminates the optoisolator, reduces component count, and extends lifetime by avoiding primary-side aluminum electrolytic bulk capacitors. Designs achieve low THD (<10%) and meet international harmonic requirements.