The WT7181R is a high performance multi-mode (CCM/Valley Switching) Flyback PWM controller. It is specifically designed to work with USB PD controller to provide a total solution for quick cell phone charger or USB PD. It minimizes the components counts and is available in a tiny SOT-26 package. The controller operates in Continuous Current Mode (CCM) during heavy load and operates in discontinuous conduction mode with valley switching during light load. 

The WT7181R helps to improve the overall efficiency and optimize the product performance. The controller provides with important protection features, such as DC Brown In/Out, Vo UVP, VDD OVP, OLP, OCP and Output Short Circuit Protection.