| 摘要 |
PURPOSE:To provide a power unit for a cathode discharge tube that is able to reduce the cost in production as well as to miniaturize the power unit. CONSTITUTION:This power unit is provided with a power source Ei, a voltage control circuit 1 controlling the extent of voltage from the power source Ei, a transformer T parallelly connected to this voltage control circuit 1, a cathode discharge tube L connected to the secondary winding of this transformer T, and a current detector 4 detecting a current flowing into this cathode discharge tube and inputting a feedback signal into the voltage control circuit 1, respectively. In addition, this power unit is constituted so as to detect any variation in the current flowing into the cathode discharge tube L by the current detector 4, feeding back the detected value to the voltage control circuit 1, and to impress the output voltage conformed to a feedback value to the aforesaid transformer T through the voltage control circuit 1 as well as to generate such a voltage as making the current so as to be constant to the secondary winding. |
