Abstract：In order to solve the current situation that mine power supply grid's power cut leads to the communication and monitoring equipment cannot work normally, a kind of mine DC uninterruptible power supply is designed. By using a step-down DC / DC converter MC34063 as well as UC3906 and LM339 to achieve the management of the uninterrupted power supply, AC power supply system is powered when AC power supply is normal, and the system is powered by battery power supply when AC failure occurs. It meets the requirements of the mine uninterrupted power supply, and the battery can work at least two hours. The simulation test results show that DC uninterruptible power supply has a certain practicality.

Keyword：DC uninterruptible power supply;MC34063;UC3906;