针对采用掉电方式进行MCU 节电设计时能否用硬件复位实现快速唤醒，分析讨论了上电复位、运行复位和掉电复位等三类复位方式的一些区别和特点，得出了掉电复位唤醒所需时间远小于上电复位、复位信号应维持多宽方能快速唤醒MCU、以及采用片外时钟可使复位唤醒速度最快等结论。关键词：快速唤醒；节电设计；掉电方式；单片机应用Abstract: How to use hardware reset to fast terminate the power-down mode of microcontroller is mportant for such power saving design. It is discussed that what the differences are among the hree reset modes of power-on, running, and power-down. And it is concluded that the reset time aken by terminating the power-down mode is less than the time taken by power-on, and how long he reset signal should be held to implement fast terminating of the power-down mode, and using xternal clock is the fastest way to terminate the power-down mode of microcontroller.Key words: fast terminate the power-down mode; power consumption reduction; power-downmode; microcontroller application