Patent ID: 7301292

Claim:
A circuit arrangement for operating at least one first (LP 1 ) and one second (LP 2 ) lamp which can be inserted in said circuit arrangement, each lamp (LP 1 ; LP 2 ) having a first (W 11 ; W 21 ) and a second filament (W 12 ; W 22 ), having a drive circuit ( 18 ) for the purpose of driving the at least one first (LP 1 ) and second (LP 2 ) lamp, the drive circuit ( 18 ) being designed to operate the at least one first (LP 1 ) and second (LP 2 ) lamp using a radiofrequency signal, characterized in that it also comprises: a comparator circuit ( 10 ) for the purpose of comparing a first (U 6 ) and a second (U 7 ) voltage potential within the circuit arrangement, and a deactivation apparatus ( 16 ) for the purpose of deactivating the drive circuit ( 18 ), the comparator circuit ( 10 ) being designed to activate the deactivation apparatus ( 16 ) if the difference between the first (U 6 ) and the second (U 7 ) voltage potential exceeds a predeterminable limit value during operation of the at least one first (LP 1 ) and one second (LP 2 ) lamp using a radiofrequency signal.