An electrical device includes a brushless one-phase driving motor which drives a mechanical unit. The brushless one-phase driving motor includes a motor rotor which is radially permanently magnetized and which rotates around a rotational rotor axis, a non-symmetric stator back-iron structure which includes a rotor opening for the motor rotor and a lateral bridge portion which magnetically connect two stator poles, a single stator coil which surrounds the lateral bridge portion, a pole separation gap arranged radially opposite to the lateral bridge portion, the pole separation gap magnetically separating the two stator poles, an electronic control device which drives the single stator coil, and a single hall sensor which is electrically connected to the electronic control device. The single hall sensor is arranged approximately radially opposite to the single stator coil with respect to the rotational rotor axis.