Toshiba Lighting & Technology Corporation

Kabushiki Kaisha Toshiba

Panasonic Corporation

Panasonic Electric Works Co., Ltd.

Hiroshi Terasaka

Masahiko Kamata

Naoko Iwai

Hirokazu Otake

Takuro Hiramatsu

Koji Takahashi

Yosuke Saito

Takeshi Saito

Hiroshi Kubota

Hitoshi Kawano

Hiroki Nakagawa

Masatoshi Kumagai

Mitsuhiko Nishiie

Katsunobu Hamamoto

Hiroyuki Sako

Hiromichi Nakajima

Toshihiko Sasai

Hideo Kozuka

Tomokazu Usami

Keiichi Shimizu

Tatsuya Konishi

Noriyuki Kitamura

Shinichiro Matsumoto

Toshiyuki Hiraoka

Kenji Sakai

Kazuhiko Sato

Toru Ishikita

Go Kato

Kiyoteru Kosa

Hiroyuki Kudo

Hirokazu Ohtake

A power supply device includes a control circuit and a first circuit. The control circuit switches between a current control mode and a voltage control mode according to an inputted dimming signal and thus dims a light-emitting element. In the current control mode the control circuit controls an output current supplied to the light-emitting element to a target current, and in the voltage control mode the control circuit controls an output voltage supplied to the light-emitting element to a target voltage. The first circuit detects the output current and the output voltage, and sets the target voltage at which switching between the current control mode and the voltage control mode is carried out as a first voltage.

Power supply device and luminaire

A dedicated power source for LED lamps capable of reliably detecting attachment of an LED lamp is provided. A dedicated power source has a DC power source portion, and includes a lighting circuit which receives power supplied from the DC power source portion and light-controls an LED lamp including an LED element and a detection resistor connected in parallel to the LED element and an attachment detecting portion for detecting attachment of the LED lamp based on a voltage level changing in accordance with attachment/detachment of the detection resistor by attachment/detachment of the LED lamp.

Power source unit for LED lamps, and LED lamp system

A DC power source unitis provided which boosts source voltage from a power source portion. A lighting circuitis provided which supplies DC voltage to loads, the DC voltage being obtained by stepping down output current of the DC power source circuit. A control circuitis provided which controls the lighting circuitin accordance with at least either voltage or current of LEDsand controls the DC power source unitso that a ratio of output voltage to voltage of the LEDsbecomes a preset fixed ratio.

DC power source unit and LED lamp system

According to one embodiment, a luminaire includes a lighting circuit configured to light a light source with a power supply from the outside, an accumulated-lighting-time storing section configured to store accumulated lighting time of the light source, and a control circuit configured to control the lighting circuit in a set mode. The control circuit sets, if a pattern for turning on and off the power supply from the outside is a predetermined initial illuminance correction setting pattern, a mode in an initial illuminance correction mode for performing initial illuminance correction corresponding to the accumulated lighting time of the light source. The control circuit sets, if the pattern for turning on and off the power supply from the outside is a predetermined normal setting pattern, the mode in a normal mode for not performing the initial illuminance correction.

Power supply device, luminaire and power source system

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

According to one embodiment, a lighting device includes a control circuit that includes a threshold for a case where a pair of the illumination lamps are connected in series between a positive output end and a negative output end of a power supply circuit, and a threshold for a case where one illumination lamp is connected between the positive output end and the negative output end of the power supply circuit. The control circuit determines the connected lamp number of the illumination lamps to a direct-current power supply device based on a voltage between the positive output end and the negative output end of the power supply circuit and a voltage between a non-potential connection end and the positive output end or the negative output end, and selects the threshold corresponding to the connected lamp number to control the direct-current power supply device.

Lighting device and luminaire

In one embodiment, a DC power supply unit includes a DC power supply source; a load circuit connected to an output end of the DC power supply source; a load state detection device to detect a load voltage or an electric quantity corresponding to the load voltage; and a control device to receive the detected output of the load state detection device. The control device controls a maximum output voltage of the DC power supply source so that the voltage difference between the maximum output voltage of the DC power supply source and the load voltage at the time of normal operation falls within a predetermined range in which arc discharge is suppressed.

DC power supply unit and LED lighting apparatus

The LED lighting device includes a lighting circuit unit, a current detecting unit, a voltage detecting unit, and a control unit. The lighting circuit unit is adapted in use to be connected to a lamp socket to be connected to a LED lamp, and is configured to provide an output voltage in the form of a DC voltage to the lamp socket in a manner to turn on the LED lamp. The current detecting unit is configured to detect an output current which is caused by the output voltage and is supplied from said lighting circuit unit to said lamp socket. The voltage detecting unit is configured to detect the output voltage of said lighting circuit unit. The control unit configured to control the lighting circuit unit. The control unit is configured to perform constant-current control of control the lighting circuit unit in a manner to regulate the output voltage such that the output current is identical to a target value while keeping the output voltage not higher than a maximum-load voltage, when the output current detected by the current detecting unit is not less than a predetermined threshold value, and is configured to perform no-load control of controlling the lighting circuit unit in a manner to regulate the output voltage such that the output voltage is kept identical to a no-load voltage higher than the maximum-load voltage, when the output current detected by the current detecting unit is less than the predetermined threshold value.

LED lighting device

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

An LED lighting device includes light emitting diode, a current control circuit having a first series circuit of first and second switching elements, a second series circuit of third and fourth switching elements, and a condenser, which is configured so that the first and second series circuits are parallel connected and the condenser is connected between a connection point of the first and second switching elements and a connection point of the third and fourth switching elements, and a control circuit for alternatively on-off controlling a pair of the first and fourth switching elements and a pair of the second and third switching elements.

LED lighting device and lighting equipment

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

Electronic ballast and lighting fixture

Growing community of inventors

Yokosuka, Japan

Hiroshi Terasaka