DER-612: 400mA @ 30V, 90 ~ 265 VACin

This engineering report describes a constant voltage (CV) output 12 W isolated flyback power supply with a valley-fill passive power factor correction circuit for smart lighting applications. The power supply is designed to provide a 30 V constant voltage output across 0 mA to 400 mA output current load and throughout the input voltage from 90VAC to 265 VAC.

The power supply IC controller device, InnoSwitch-CH combines primary, secondary and feedback circuits in a single surface-mounted off-line flyback switcher IC. It incorporates the primary FET, the primary side controller and a secondary-side synchronous rectification controller. The device also includes an innovative new technology, FluxLink™, which safely bridges the isolation barrier and eliminates the need for an optocoupler.

The added valley-fill passive power factor correction circuit is a simple and low cost solution to meet power factor requirements for lighting applications.

DER-612 using InnoSwitch-CH offers a highly efficient constant voltage supply with a fast transient load response. The design achieves high power factor (0.9) at low line. The key design goals were high efficiency, optimized power factor and low components count.

The document contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, design spreadsheet, sample actual application circuit in Appendix section, and performance data.