| 摘要 |
The electronic ballast has a rectifier arrangement (1)-which is fed by AC power supply voltage (U)-with active step-up converter (SW2), a storage capacitor (C2), a network for limiting an inrush current and two outputs, at which a stabilized DC voltage (U+) referred to housing ground as reference potential (Uref) is output. An inverter (2) is connected to the rectifier arrangement, a load circuit (3) with at least one fluorescent lamp (La1 and/or La2) being assigned to said inverter on the output side. The inverter has a converter network (T1/1, T1/2, C1, SW3, SW4), preferably designed as a push-pull circuit, with two bridge paths, which, in the steady-state operating condition, are alternatively switched through to the reference potential. In this case, the switching network for limiting the inrush current comprises a limiting resistor (R1), which, in series with the storage capacitor (C2), is connected to reference potential. The junction point between the storage capacitor and the limiting resistor is coupled to the two bridge paths of the converter network in such a way that it is connected, in the steady-state condition of the inverter, via the latter to housing ground and the limiting resistor, which is thus effective only in the switch-on phase, is bridged.
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