| 摘要 |
A lighting apparatus of an electronic circuit, which is substituted for an ordinary glow lamp, and lights a discharge lamp fitted with filament electrodes such as a fluorescent lamp by causing satisfactory preheating current to flow through the filament electrodes and by giving a stable kick pulse between them, and is easy to be made into an integrated circuit. The apparatus is characterized by the following. It is a two-terminal network connected between two electrodes (P, Q) of a lamp (3). One terminal (Q) of the two terminals is a common electrode. It has a negative DC power supply (27) which is charged in the negative half cycles of an AC power supply. When the non-discharge of the lamp is sensed in a negative half cycle of the AC power supply, this is stored in the apparatus by utilizing the negative DC power supply. Thereby, a thyristor (5) connected between the two terminals is turned on and consequently a preheating current (I1) continues to flow through the filaments on and after a zero crossing point where the AC voltage shifts to the next positive half cycle. When the preheating current (I1) decreases under preset value (I0), reverse bias current is made to flow from the negative DC power supply to turn off the thyristor (5) and thereby to generate a kick pulse (Vk). |
