Toshiba Lighting & Technology Corporation

Kabushiki Kaisha Toshiba

Takuro Hiramatsu

Hirokazu Otake

Mitsuhiko Nishiie

Keiichi Shimizu

Masatoshi Kumagai

Sumio Hashimoto

Masaru Inoue

Masahiko Kamata

Hiroshi Terasaka

Toshiyuki Hiraoka

Naoko Iwai

Hajime Osaki

Tsutomu Araki

Hiroshi Kubota

Shinya Hakuta

Shigeru Osawa

Hitoshi Kawano

Takeshi Hisayasu

Yusuke Shibahara

Kenji Sakai

Katsusuke Uchino

Hiromichi Nakajima

Go Kato

Fumihiko Nagasaki

Mitsuhiro Matsuda

Hiroshi Takenaga

Katsuya Ooto

Hirokazu Ohtake

Tomoaki Shimizu

Chikako Katano

Sumio Hashimto

A power supply device according to one embodiment is configured to control a lighting of semiconductor light-emitting elements, wherein a dimming signal is canceled during a predetermined time period (T) from a timing immediately after power-ON, so as to light on light-emitting diodes to have a predetermined light amount, for example, a minimum light amount. After an elapse of the predetermined time period (T), cancellation of the dimming signal is released to light on the light-emitting diodes to have a light amount instructed by the dimming signal.

Power supply device and lighting equipment provided with power supply device

According to one embodiment, a power supply device includes a rectifying circuit configured to rectify an alternating-current power supply, a first capacitor configured to smooth a voltage after rectification, and a falling voltage chopper circuit configured to supply electric power to a load. The first capacitor is set to a capacity in which a section where a voltage after smoothing drops to an output voltage to the load is provided in a rectified half period of the alternating-current power supply. The falling voltage chopper circuit includes at least one switching element configured to receive an input of the voltage after smoothing, operate in a section where the voltage after smoothing exceeds the output voltage, and pause in a section of the output voltage and a second capacitor provided on an output side and having a capacity larger than the capacity of the first capacitor.

Power supply device with smoothing capacitor and falling voltage chopper circuit

A lighting circuit according to embodiments includes: a self-hold element connected in series to an AC power source that generates power for lighting an illumination load, together with the illumination load, the self-hold element being configured to control supply of the power provided by the AC power source to the illumination load by the self-hold element being turned on/off; a noise prevention circuit connected in parallel to the self-hold element; and a damping circuit configured to connect a damping resistance to the noise prevention circuit parallely only for a predetermined period from turning-on of the self-hold element, thereby preventing the self-hold element from being repeatedly turned on/off during a period in which the self-hold element is on under normal conditions, due to a transient during power supply.

Lighting circuit and illumination device

A luminaire according to one embodiment includes a DC power supply circuit, a switching power supply, and a lighting load. The DC power supply circuit converts an AC voltage controlled in phase to a DC voltage. The switching power supply is connected to the DC power supply circuit, and is controlled so that an input current becomes a constant current. The lighting load is connected as a load circuit of the switching power supply.

Luminaire

In a power supply device according to one embodiment, a reference signal (Vref), which changes from a value corresponding to a maximum current in a full lighting state to that corresponding to a minimum current in case of a deepest dimming depth, and a reference signal (Vref), which changes from a value corresponding to a load voltage at the time of a maximum current in a full lighting state to that corresponding to a minimum current in case of the deepest dimming depth, are prepared in accordance with dimming depths of a dimming signal. In a shallow dimming depth region close to a full lighting state, the reference signal (Vref) is selected to apply constant-current control to light-emitting diodes in a current control mode. In a deep dimming depth region, the reference signal (Vref) is selected to apply constant-voltage control to the diodes in a voltage control mode.

Power supply device and lighting equipment

A light-emitting device and an illumination apparatus are disclosed. A plurality of LED elements are connected in series between positive and negative lines, and first bypass capacitor is connected in parallel to the LED elements respectively. Each series circuit of a predetermined number of LED elements is connected in parallel to second bypass capacitors. As a result, with the negative power line set as a grounding point, the AC impedance at connection points of the series circuit of the LED elements against the ground is reduced. Thus, the erroneous lighting or 'flicker' of each LED which otherwise might be caused by an external noise is prevented.

Light-emitting device and illumination apparatus

In a power supply unit, if a dimmer rate is changed within a range of k, k, . . . kby a dimmer signal k of a dimmer signal generator, light-emitting diodes are controlled to be lighted by a constant current characteristic in an area where the dimmer rate is small according to a load characteristic corresponding to the dimmer rates k, k, . . . k. As the dimmer rate becomes larger, a tendency of a constant voltage characteristic is gradually strengthened from a constant current characteristic so that the light-emitting diodes are lighted at the larger dimmer rate.

Power supply unit having dimmer function and lighting unit

Certain embodiments provide an LED lighting equipment including a lighting main body. An LED power device has a DC power source and a DC-DC converter having an input terminal connected to the DC power source and the DC-DC converter having an output terminal. An LED light source has a board and a plurality of LED packages; each including a plurality of LED chips connected in series. The LED packages are mounted on the board and connected in series to the output terminal of the DC-DC converter.

LED lighting equipment

Light emitting diode module

A light-emitting module includes a module substrate, semiconductor light-emitting elements and a connection substrate. On one face of the module substrate, a conductive layer is formed. The semiconductor light-emitting elements and the connection substrate are mounted on the conductive layer of the module substrate. Electric wires, which extend from a lighting circuit, are connected to the connection substrate. Power is supplied to the semiconductor light-emitting elements through the connection substrate and the conductive layer of the module substrate.

Light-emitting module, self-ballasted lamp and lighting equipment

There is provided an LED lighting device having a satisfactory temperature characteristic and a small amount of variation in output current. The step-down chopper is provided with a first circuit including the switching element, the impedance means and a first inductor connected in series and a second circuit including the first inductor and a diode connected in series. A self-excited drive signal generation circuit is provided with a second inductor magnetically coupled with the first inductor and applies a voltage induced in the second inductor to the switching element to keep the switching element on. A turn-off circuit outputs an output voltage when the voltage of the impedance means detected by a comparator exceeds the reference value, and the output voltage allows a switching element to turn on to short-circuit the output terminals of the self-excited drive signal generation circuit, resulting in that the switching element is turned off.

Light-emitting diode lighting device with step-down chopper

Growing community of inventors

Yokosuka, Japan

Takuro Hiramatsu