This thread has been locked.
If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.
Original question:
UCC28780: 芯片VDD到达启动阈值VDDon后不启动,SWS引脚的电压不下降至11V,RUN引脚不使能
原理图如图所示,带载5W但输出电压立马从18V降到10V,且纹波变大
HI
确认一下变压器设计,以及电流保护。