| 摘要 |
PCT No. PCT/AT88/00113 Sec. 371 Date Jun. 15, 1990 Sec. 102(e) Date Jun. 15, 1990 PCT Filed Dec. 16, 1988 PCT Pub. No. WO89/06085 PCT Pub. Date Jun. 29, 1989.A novel circuit for igniting and operating gas discharge lamps, in particular metal vapour lamps, comprises a buffer capacitor (C4) connected to a direct-current voltage (1,2) and connected in parallel with a circuit consisting of a choke and a capacitor connected in series (L1, C1). An electronic switch (S), for example a transistor and a recovery diode (D), is connected in parallel with the capacitor (C1). A second choke-capacitor series circuit (L2, C3) connected in series with the metal vapour lamp (L) is connected in parallel with the capacitor (C1), which is connected in parallel with the electronic switch (S). A second capacitor (C2) is directly connected in parallel with the the metal vapour lamp (L). The ignition circuit and the power supply circuit for the metal vapour lamp (L) are combined in this fluorescent lamp ballast, thus obviating the need for a separate ignition circuit. In addition, the circuit operates independently of the supply voltage. |
