稳定电压电流显示，尾数基本不跳，屏幕显示高位灭0,

功率超20W，启动风扇（P2.5口输出信号，可以控制风扇）包括原理图-英语　　 简体中文 繁体中文

Stable voltage and current display, mantissa does not jump, display high off the screen 0,

Power 20W, start the fan (P2.5 output signal, you can control the fan) including schematics