As the fluorine atom generator,the discharge tube plays an important role in discharge-driven CW HF/DF chemical laser system. The discharge scheme widely employed currently is the high voltage DC power which uses ballast resistor to restrict current and the typical electrical parameter scales are several kilovolt and hundred milliampere. The traditional theory and results of experiments indicate that yield rate of fluorine atom is proportional to the input power of discharge tube; accordingly the laser power is proportional to the input electric power. Using resistances of different levels,for the same input power the scheme of low voltage and large current is easier to gain high laser power output than that of high voltage and low current.