| 摘要 |
PCT No. PCT/DE93/01079 Sec. 371 Date Feb. 13, 1995 Sec. 102(e) Date Feb. 13, 1995 PCT Filed Nov. 11, 1993 PCT Pub. No. WO94/12007 PCT Pub. Date May 26, 1994A circuit arrangement for high-frequency operation of a low-pressure discharge lamp (18) includes a mains rectifier (10), a radio interference suppression filter (12) connected to the mains rectifier (10), an RF inverter (14), connected to the direct current output of the mains rectifier (10) and having two alternatingly switching transistors (T1, T2) along with an inductance (LK), a trigger circuit and a center tap (M), which is between the two transistors (T1, T2). A filter capacitor (CS) is connected parallel to the switching paths of the two transistors (T1, T2) of the RF inverter (14). A series resonant circuit (16) is assigned to the low-pressure discharge lamp (18), and comprises a resonant inductance (L3), a coupling capacitor (C3), and a resonant capacitance parallel to the lamp. The connection lines for the low-pressure discharge lamp (18) lead on the one hand from a first electrode (E1) via the resonant inductance (L3) to the center tap (M) and on the other from a second electrode (E2) via the center tap of a diode series circuit, connected in the direct current forward direction in series with the filter capacitor (CS) and comprising a first and a second diode (D1, D2), to the positive and negative terminal, respectively, of the mains rectifier (10). The capacitance parallel to the lamp of the series resonant circuit (16) assigned to the low-pressure discharge lamp (18) comprises two parallel-connected capacitors (CR1, CR2); one (CR2) of the capacitors (CR1, CR2) parallel to the lamp is connected directly to the positive or negative terminal of the filter capacitor (CS).
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