Abstract: A transformer includes primary and secondary windings coupled electromagnetically to each other and wounded respectively around primary and secondary winding portions of a bobbin unit, and a core unit mounted to the bobbin unit and including first and second core parts that form a magnetic circuit path. The first core part includes insertion and extension segments extending from a connecting segment. The second core part includes insertion and extension segments, and an adjusting segment extending from a connecting segment toward the first core part. The extension segments of the first and second core parts contact each other. The insertion segments of the first and second core parts extend respectively through the primary and secondary winding portions to contact each other.

Abstract: A transformer includes primary and secondary windings coupled electromagnetically to each other and wounded respectively around primary and secondary winding portions of a bobbin unit, and a core unit mounted to the bobbin unit and including first and second core parts that form a magnetic circuit path. The first core part includes insertion and extension segments extending from a connecting segment. The second core part includes insertion and extension segments, and an adjusting segment extending from a connecting segment toward the first core part. The extension segments of the first and second core parts contact each other. The insertion segments of the first and second core parts extend respectively through the primary and secondary winding portions to contact each other.

Abstract: A current balancing circuit for first and second lamp sets includes a step-up transformer and a current balancer. The step-up transformer is adapted to be coupled to a power supply for receiving an alternating-current source power, and for generating a drive signal by varying magnitude of the alternating-current source power. The step-up transformer is further adapted to be coupled to the first and second lamp sets for providing the drive signal thereto. The current balancer includes first and second shunt transformers. Each of the first and second shunt transformers includes primary and secondary windings that correspond to each other in number of turns thereof. The first and second shunt transformers are adapted to be coupled to corresponding discharge lamps of the first lamp set. The current balancer is adapted to mirror current flowing through the first and second shunt transformers to the second lamp set.

Abstract: A transformer includes a bobbin unit, a primary winding, a secondary winding, and a core unit. The bobbin unit has a first winding portion and a second winding portion. The primary winding is wound around the first winding portion of the bobbin unit. The secondary winding is wound around the second winding portion of the bobbin unit, and is coupled electromagnetically to the primary winding. The core unit is mounted to the bobbin unit, and includes a first core part, and a second core part that forms a magnetic circuit path with the first core part. The first core part is movable relative to the second core part from a tunable position to an assembled position for varying a size of an effective magnetic flux region defined between the first core part and the second core part.

Abstract: A lamp driving circuit includes a step-up transformer, a detector, and a controller. The step-up transformer includes a primary winding, and a secondary winding configured to cooperate with a discharge lamp to form a tank circuit that generates a tank current. The detector is adapted for detecting current magnitude of current flowing through the discharge lamp, and outputs a detecting signal corresponding to the current magnitude. The controller receives the detecting signal from the detector, and generates a drive signal for driving the step-up transformer. The controller includes a capacitor, and configures a waveform of the drive signal by controlling charging of the capacitor based on a calculation value that corresponds to a frequency of the drive signal, a start-setting value, and a difference between the detecting signal and a current-setting signal.

Abstract: An inverter transformer includes a coil unit and a transformer core unit. The coil unit includes a bobbin formed with a core-receiving compartment, and a plurality of windings including two primary windings and two secondary windings wound around the bobbin. The secondary windings are disposed adjacent to each other and are coupled electromagnetically and respectively to the primary windings. The transformer core unit includes an internal core part that extends into the core-receiving compartment of the bobbin, and an external core part that forms a magnetic circuit path with the internal core part. The external core part includes a main segment extending externally at one side of the bobbin and a protrusion segment extending from the main segment toward a portion of the bobbin that is disposed between the secondary windings.

Abstract: An inverter transformer includes a coil unit including a bobbin and a plurality of windings, and a transformer core unit. The bobbin is formed with a core-receiving compartment, and includes first, second and third coil winding portions. The windings are wound around the first, second and third coil winding portions, respectively. The transformer core unit has an internal core part that extends into the core-receiving compartment.

Abstract: A method for adjusting mutual inductance is adapted for use in a transformer including a main core and two windings that are wound on the main core and that have the mutual inductance established therebetween. The method includes the steps of: (A) disposing an adjusting core between the windings and adjacent to the main core, the adjusting core having a cross-sectional area smaller than that of the main core; and (B) without resulting in division of flux of the mutual inductance established between the windings, and division of an exciting magnetic flux into a plurality of independent magnetic paths, adjusting position of the adjusting core relative to the main core to vary the mutual inductance established between the two windings.

Abstract: A circuit includes a first circuit including therein a first coil connected to a power source and a first capacitance component, and a second circuit including therein a second coil connected to the power source and a second capacitance component, wherein the second coil is avenged so as to generate a magnetic field in such a direction as to offset a magnetic field generated by a current flowing through the first coil. Here, a self inductance of the first coil is substantially the same as a self inductance of the second coil, currents flowing through the first and second coils are made substantially the same by a mutual inductance between the first and second coils, a leakage inductance component of the first coil and the first capacitance component form a resonance circuit, and a leakage inductance component of the second coil and the second capacitance component form a resonance circuit.

Abstract: An inverter transformer includes a coil unit including a bobbin and a plurality of windings, and a transformer core unit. The bobbin is formed with a core-receiving compartment, and includes first, second and third coil winding portions. The windings are wound around the first, second and third coil winding portions, respectively. The transformer core unit has an internal core part that extends into the core-receiving compartment.