Zero current half-bridge soft switch circuit, the power supply is featured by high efficiency and rapid response, and easy to match tubes of manufacturers. It has simple port control, fits high and low level signals, can control start and stop through TTL level, and is equipped with abnormal protection switch to detect if there is water or ventilation outside. Power can be regulated by inputting 0-5V simulation signal or inputting PWM signal. The power supply has open circuit protection function: Under the condition of good earthing protection, the power supply can work in open circuit in short time, and then it can avoid the damage caused by tube cracking. Ex-factory aging test Each power supply can undergo a 12h aging test at high temperature of 60ºC on full load, and 500 times of 7sec power-on/off tests.