A control circuit (1) for driving a gas discharge lamp, in particular a
fluorescent lamp (FL), having a controllable converter (2) for converting
a DC voltage to an AC voltage and having two feed lines (3, 4), which are
connected on the AC-voltage side to the converter (2), and between which
the gas discharge lamp can be connected, an inductor (L1), a first
capacitance (C1) and a first controllable switching element (T1) being
connected in series in the feed lines (3, 4). The feed lines (3, 4) are
connected to one another via a second switching element (T2). A control
unit (ST2) controls the switching elements (T1, T2, T3) in synchronism
with the AC voltage of the converter (2) and is designed such that the
second switching element (T2) is opened after a closed phase for the
purpose of starting the gas discharge lamp at such a point in time that
the AC voltage at the inductor (L1), which is set in the resonant circuit
including the inductor (L1) and the parasitic capacitance (C4) of the
second switching element (T2), and the AC voltage of the converter (2),
approximately in-phase in terms of their extrema, are added to give a
starting voltage. Furthermore, provided is a corresponding method for
driving the gas discharge lamp.