This document introduces the EVL6566B-40WSTB demonstration board produced by STMicroelectronics. The demonstration board is a 40W wide input range flyback converter designed for digital consumer equipment. It features multiple output voltages, including 1.8V/1.73A, 3.3V/0.5A, 5V/2.4A, and 12V/1.9Avg÷2.9Apk, dedicated to digital circuitry, analog peripherals, HDD/DVD, and other circuits. In addition, the demonstration board also features low standby power consumption and short circuit protection.