Sony Corporation

Kenji Iwai

Hiroshi Sakamoto

Junzo Watanabe

Seiji Kawaberi

Akihiro Ueyama

A fluorescent-lamp-driving device contains a driving control circuit that receives direct current power voltage and a lamp control signal for performing drive control on fluorescent lamps and converts the direct current power voltage to alternating current power voltage, and a transformer containing a winding at its primary side and windings for driving a heater and for maintaining discharge at its secondary side. The alternating current power voltage is supplied to heaters of the fluorescent lamps at their high electric potential side. The driving control circuit increases the frequency of the alternating current power supply to a frequency thereof in which voltage of the fluorescent lamps is equal to a discharge start voltage of the fluorescent lamps or less based on the lamp control signal at a period of starting-up time of the fluorescent lamps.

Fluorescent lamp driving device and liquid crystal display apparatus using the same

A transformer includes: a primary winding receiving portion having a primary winding wound around an axis; and a pair of secondary winding receiving portions each having a secondary winding wound around an axis and disposed on the opposite sides of the first primary winding receiving portion with a gap left in the axial direction. The gaps are formed in a size of a value higher than a first predetermined value, and the coupling coefficients between the first primary winding and the two secondary windings are set lower than a second predetermined value by the gaps.

Transformer, backlight apparatus, and display apparatus

Disclosed herein is a transformer including: an iron core; and a winding wound around the iron core; wherein the iron core includes a column-shaped output side iron core part, a plurality of column-shaped input side iron core parts, and a connecting iron core part, the winding includes a plurality of primary windings, a secondary winding, and generated magnetic fluxes.

Transformer

A switching power source apparatus reduces power loss and improves conversion efficiency of a switching power source part by rectifying and smoothing a commercially available alternating power source supplied to an oscillation drive circuit and a switching circuit part that constitutes a half-bridge circuit. An output of the half-bridge circuit is grounded via a resonance capacitor, a choke coil, and a primary winding of an insulated type converter transformer. This converter transformer has a secondary winding for obtaining a &plus;B voltage and high-voltage windings for obtaining a high-level output voltage. Further, fluctuation in the voltage of the high-level output voltage is supplied to the oscillation drive circuit via resistors, a control circuit, and a photo-coupler, whereby the switching circuit part is controlled. The secondary winding is connected in series to a saturable reactor, so that by controlling the inductance of this saturable reactor, the &plus;B voltage taken out from the secondary winding is controlled.

Switching power source apparatus

A coil (11) is connected in series to a primary winding (1a) of a flyback transformer (1). A series circuit of a capacitor (15) and a switching circuit (12) is connected in parallel to the coil (11). By turning on and off the switching circuit (12), the connection of the capacitor (15) to the coil (11) is switched, to thereby connect or disconnect the coil (11) in an AC fashion. Therefore, it is possible to realize a high voltage regulating circuit which can be made inexpensive.

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Kanagawa, Japan

Kenji Iwai