Digital high-power-factor XDP™ controller for cost-effective, dual-stage LED drivers with secondary-side regulated constant voltage output The XDP™ digital power XDPL8219 is a high-performance secondary-side regulated flyback controller with high power factor and constant voltage output. The device operates in quasi-resonant mode (QRM) to maximize the efficiency and minimize the electromagnetic interference (EMI) over a wide load range. It enters active burst mode (ABM) at light load to prevent audible noise from being heard, while achieving no-load standby power as low as <100mW.