A circuit arrangement (3) is provided for operating at least one low-power lighting unit with a power supply (4) and in particular with a self-oscillating power supply. The circuit arrangement (3) comprises at least an input (12) for receiving an operating voltage (28) from said power supply (4) and an output (11) for connection to one or more low-power lighting units. To allow an efficient operation of said low-power lighting unit with the power supply (4), the circuit (3) comprises a pulse generator (17), connected with said input (12) and adapted to inject at least one trigger pulse (40a, 40b) into said power supply (4) during operation.