摘要 |
A circuit arrangement for starting and operating one or more discharge lamps comprising a self-oscillating inverter (1), a resonant circuit (2), a low-pressure discharge lamp (5), a starting voltage controller (3) with a variable resistor (R1), and a lamp filament heating controller (4), wherein the lamp filament heating controller includes an additional variable resistor (R2) in the resonant circuit, which variable resistor measures the current flowing in the resonant circuit, and, in the event of a threshold value being exceeded, disconnects the half-bridge transistor (Q2) and thus limits the current flowing in the resonant circuit, this additional variable resistor (R2) being bypassed by a switch (Q3), depending on the lamp state. |