Nichia Corporation

Harumi Sakuragi

Wataru Ogura

Minoru Kitahara

Teruo Watanabe

Yoshinori Shimizu

Ryuhei Tsuji

Tomoaki Inuzuka

Yasuhiro Kunisaki

Masayuki Taru

Katsunori Mitani

An LED driving apparatus is provided. The apparatus includes an LED Portion, a charging/discharging capacitor, a capacitor charging and discharging paths, and a capacitor charging constant current portion. The LED driving portioncontrols a current in the LED portion. The capacitoris connected in parallel to the LED portion. The charging and discharging paths are connected to the capacitor whereby charging and discharging the capacitor, respectively. The constant current portionis connected on the charging path and controls a charging current so that the capacitor is charged at a constant current. When rectified voltage applied to the LED portion becomes high, the capacitor is charged with the charging current through the charging path. When the voltage becomes low, the capacitor is discharged at a discharging current through the discharging path so that the discharging current is applied to the LED portion.

Light-emitting diode driving device for reducing light off period

A charging diodeis connected to the capacitorand the anode of a first LED, and limits the direction of the charging current. A discharging diodeis connected to the capacitorand the cathode of the first LED, and limits the direction of the discharging current. A charging path CP is provided which includes the capacitor, the charging diode, and the charger. The capacitoris charged through the charging path CP. A discharging path DP is provided which includes the capacitor, the discharging diodeand a discharger. The capacitoris discharged through the discharging path DP. A transient path TP is provided which does not include the capacitorbut includes the first LED, the chargerand the discharger

Light-emitting diode driving apparatus including charging/discharging capacitor

An apparatus includes first and fourth bypasses, a current detector, and a current controller. The first bypass is connected serially to a first LED, and controls the current amount in the first LED. The fourth bypass is connected serially to a second LED, and controls the current amount in the first and second LEDs. The detector detects current detection signal based on the current amount on an output line along which the first and second LEDs are connected serially to each other. The controller provides control signal for controlling the first and fourth bypasses based on the detection signal. The controller includes one output for providing the control signal. The first and fourth bypasses are connected in parallel to the one output.

Light-emitting diode driving apparatus

An LED driving apparatus for suppressing harmonic components is provided. First and fourth portionsandare in parallel to the first and second LEDsand, respectively. The first portioncontrols the current amount in said first LED. The fourth portioncontrols the current amount in said first and second LEDsand. The first and fourth controllersandcontrol the first and fourth portions, respectively. A current detectordetects a signal based on the amount of a current flowing from the first and second LEDsand. A signal providing portionprovides a voltage based on a rectified voltage provided from a rectifying circuit. The first and fourth controllersandcompare the current detection signal with the signal voltage, and control the first and fourth portionsandbased on the comparison.

Light-emitting diode driving apparatus for suppressing harmonic components

A light emitting apparatus comprises at least two light emitting elements with different chromaticities; and a light emitting element controller that controls light emitted from the light emitting apparatus so as to be a desired chromaticity. The light emitting element controller controls the light emitting elements based on a predetermined function of light emitting element temperature variation. Accordingly, it is possible to provide a light emitting apparatus that, even if the temperature varies, has a stable desired chromaticity without chromaticity variation. In addition, since control is performed based on a property function of wavelength fluctuation due to light emitting element temperature variation, it is possible to provide more reliable reproduction characteristics, and a desired chromaticity.

Light emitting apparatus, LED lighting, LED light emitting apparatus, and control method of light emitting apparatus

It is an object of the present invention to provide a control circuit for charging and discharging () etc., which can prevent an undesirable-emission caused by a residual charge, capable of obtaining a high-quality display and so on. The control circuit for charging and discharging () includes a driven element (E-E) with a driving-on status and a driving-off status; a charging element, whose one end is grounded; and a driving circuit (), which is connected to the driven element (E-E), for controlling the driving-on status or the driving-off status in the driven element. The control circuit further includes a charging path, which is connected to the driven element (E-E), for charging the charging element with a residual charge, which is produced in the driven element (E-E) and/or a line connected to the driven element (E-E) during the driving-on status, and a discharging path, which is connected to the charging path, for discharging the residual charge from the charging element to a ground in the driving-on status.

Growing community of inventors

Tokushima, Japan

Harumi Sakuragi