A lamp driving apparatus wherein a plurality of two-winding balance
circuits are connected to a plurality of parallel-connected lamp groups
so that all of the lamps may be illuminated even though ambient
conditions cause some of the lamps to have low resistance. Capacitors are
connected to first electrodes and certain of the balance coil windings
are connected to second electrodes of one of the lamp groups while, in a
second lamp group, others of the balance coil windings are connected to
the first electrodes and capacitors are connected to the second
electrodes thereof, current flowing through balance coil windings to some
lamps being affected by current flowing through balance coil windings to
other lamps.