公开(公告)号：US09780875B2

公开(公告)日：2017-10-03

申请号：US14843458

申请日：2015-09-02

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Masahiro Naruo ,  Shojirou Kido

IPC: H05B37/02 ,  H05B39/00 ,  H04B10/116 ,  H05B33/08

CPC classification number: H04B10/116 ,  H05B33/0845 ,  H05B37/0272

Abstract: A visible light communication modulation circuit includes a modulation resistance circuit configured to change a current flowing through an LED light source by changing a resistance thereof, a measurement circuit configured to simultaneously measure a voltage applied to the LED light source and the current flowing through the LED light source at least twice until the current is stabilized, an calculation circuit configured to obtain an equivalent series resistance of the LED light source based on at least two sets of voltage values and current values and determine a target resistance of the modulation resistance circuit based on the equivalent series resistance and a predetermined modulation degree, and a conversion circuit configured to change the resistance of the modulation resistance circuit based on the target resistance.

公开(公告)号：US09204511B2

公开(公告)日：2015-12-01

申请号：US14433785

申请日：2013-10-10

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Sana Esaki ,  Masahiro Naruo ,  Kenichi Fukuda

IPC: H05B37/02 ,  H05B33/08 ,  H02M3/156

CPC classification number: H05B33/0845 ,  H02M3/156 ,  H05B33/0815 ,  H05B33/0818 ,  H05B33/0821 ,  H05B33/0857

Abstract: A lighting apparatus includes a chopper circuit and a control circuit that controls the chopper circuit. The control circuit includes a determining unit that determines a duty ratio of a dimming signal, and an output control unit that outputs a drive signal. The control circuit outputs a drive signal from the output control unit according to a result of a determination by the determining unit and causes the solid state light-emitting element to be lighted in a normal mode. In the charging mode, the control circuit sets an average value of a current flowing through an inductor to be higher than in the normal mode and charges a smoothing capacitor until a voltage across the smoothing capacitor reaches a prescribed voltage. When power is supplied, the control circuit charges the smoothing capacitor in the charging mode and subsequently lights the solid state light-emitting element in the normal mode.

Abstract translation: 照明装置包括斩波电路和控制斩波电路的控制电路。 控制电路包括确定调光信号的占空比的确定单元和输出驱动信号的输出控制单元。 控制电路根据确定单元的确定结果从输出控制单元输出驱动信号，并使固态发光元件以正常模式点亮。 在充电模式中，控制电路将流过电感器的电流的平均值设定为高于正常模式，并对平滑电容器充电直到平滑电容器两端的电压达到规定电压。 当供电时，控制电路在充电模式下对平滑电容器充电，随后在正常模式下点亮固态发光元件。

公开(公告)号：US09999104B2

公开(公告)日：2018-06-12

申请号：US15047446

申请日：2016-02-18

Applicant: Panasonic Intellectual Property Management Co., Ltd.

Inventor： Masahiro Naruo ,  Kenichi Fukuda ,  Shinji Makimura ,  Akira Nakajo

IPC: H05B33/08

CPC classification number: H05B33/0815 ,  H05B33/0827 ,  H05B33/0866

Abstract: A lighting device that supplies current to light-emitting units includes: a DC-to-DC converter; a switch unit connected to the light-emitting units; and a control circuit which controls the DC-to-DC converter and the switch unit. The DC-to-DC converter includes: an inductor through which current from the DC-to-DC converter is provided to the light-emitting units; and a first switch element connected in series with the inductor and which switches ON/OFF. The control circuit includes: a zero-crossing detector that detects that current flowing in the inductor is substantially zero due to the first switch element switching OFF, and outputs a zero-current detection signal; and a switch controller that selects one of the light-emitting units and controls the switch unit to cause the current from the DC-to-DC converter to be supplied to the selected light-emitting unit when the first switch element subsequently switches ON, each time the switch controller receives the zero-current detection signal.