# US 2014/0152182 A1 · Lighting device and luminaire including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0152182 A1 - Document ID: US20140152182A1 - Status: Published application - Kind: A1 - Application number: 14/093,704 - Filed: 2013-12-02 - Published: 2014-06-05 - Earliest claimed: 2012-12-04 - Assignees: Panasonic Corporation - Applicants: Panasonic Corporation - Inventors: Masafumi YAMAMOTO; Satoru NAGATA; Masato HIMEDA; Hisaya TAKIKITA; Koki MATSUI - Web page: https://patentgrep.com/patent/US20140152182A1 ## CPC - H05B 45/375: using buck topology - H05B 45/38: using boost topology - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract A lighting device (10) includes a voltage converter (2) for generating a predetermined DC voltage, a detector (4) for obtaining a detection voltage corresponding to a predetermined DC voltage applied across a light source (20), a controller (3) for controlling the voltage converter (2) so that a current flowing through the light source (20) is constant, and a determination unit (5) for determining whether the detection voltage is a preset first reference voltage or higher. The first reference voltage is set higher by a specified voltage than the detection voltage, and is set to vary more slowly than the detection voltage. The controller (3) stops an operation of the voltage converter (2) when the detection voltage is determined to be the first reference voltage or higher through the determination unit (5). ## Claims ### Claim 1 A lighting device, configured to be detachably attached with a light source comprising an LED device as a lighting object, the lighting device comprising: a voltage converter configured to convert a DC voltage supplied from a DC power supply into a predetermined DC voltage; a detector configured to detect the predetermined DC voltage applied across the light source to generate a detection voltage; a controller configured to control the voltage converter so that a current flowing through the light source is constant; and a determination unit configured to determine whether the detection voltage by the detector is a preset first reference voltage or higher, wherein the first reference voltage is set higher by a specified voltage than the detection voltage by the detector, and is set to vary more slowly than the detection voltage, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the first reference voltage or higher through the determination unit. ### Claim 2 (depends on 1) The lighting device of claim 1, wherein the light source includes a plurality of different LED devices having different rated voltages. ### Claim 3 (depends on 1) The lighting device of claim 1, wherein the light source includes at least two LED units, each of the LED units including a plurality of LED devices connected in series or parallel, and the at least two LED units are connected in series. ### Claim 4 (depends on 2) The lighting device of to claim 2, wherein the light source includes at least two LED units, each of the LED units including a plurality of LED devices connected in series or parallel, and the at least two LED units are connected in series. ### Claim 5 (depends on 1) The lighting device of claim 1, wherein the first reference voltage is set to be higher than the detection voltage in at least a specified period after a time when the predetermined DC voltage is output from the voltage converter, the detection voltage being obtained from the predetermined DC voltage. ### Claim 6 (depends on 2) The lighting device of claim 2, wherein the first reference voltage is set to be higher than the detection voltage in at least a specified period after a time when the predetermined DC voltage is output from the voltage converter, the detection voltage being obtained from the predetermined DC voltage. ### Claim 7 (depends on 3) The lighting device of claim 3, wherein the first reference voltage is set to be higher than the detection voltage in at least a specified period after a time when the predetermined DC voltage is output from the voltage converter, the detection voltage being obtained from the predetermined DC voltage. ### Claim 8 (depends on 4) The lighting device of claim 4, wherein the first reference voltage is set to be higher than the detection voltage in at least a specified period after a time when the predetermined DC voltage is output from the voltage converter, the detection voltage being obtained from the predetermined DC voltage. ### Claim 9 (depends on 1) The lighting device of claim 1, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 10 (depends on 2) The lighting device of claim 2, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 11 (depends on 3) The lighting device of claim 3, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 12 (depends on 4) The lighting device of claim 4, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 13 (depends on 5) The lighting device of claim 5, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 14 (depends on 6) The lighting device of claim 6, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 15 (depends on 7) The lighting device of claim 7, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit. ### Claim 16 A luminaire, comprising: a light source comprising an LED device; and a lighting device configured to be detachably attached with the light source, wherein the lighting device comprises: a voltage converter configured to convert a DC voltage supplied from a DC power supply into a predetermined DC voltage; a detector configured to detect the predetermined DC voltage applied across the light source to generate a detection voltage; a controller configured to control the voltage converter so that a current flowing through the light source is constant; and a determination unit configured to determine whether the detection voltage by the detector is a preset first reference voltage or higher, wherein the first reference voltage is set higher by a specified voltage than the detection voltage by the detector, and is set to vary more slowly than the detection voltage, and wherein the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the first reference voltage or higher through the determination unit. ### Claim 17 (depends on 16) The luminaire of claim 16, wherein the light source includes a plurality of different LED devices having different rated voltages. ### Claim 18 (depends on 16) The luminaire of claim 16, wherein the light source includes at least two LED units, each of the LED units including a plurality of LED devices connected in series or parallel, and the at least two LED units are connected in series. ### Claim 19 (depends on 16) The luminaire of claim 16, wherein the first reference voltage is set to be higher than the detection voltage in at least a specified period after a time when the predetermined DC voltage is output from the voltage converter, the detection voltage being obtained from the predetermined DC voltage. ### Claim 20 (depends on 16) The luminaire of claim 16, wherein a second reference voltage is previously set in the determination unit, the second reference voltage being a fixed voltage higher than the detection voltage obtained from the predetermined DC voltage, the determination unit is configured to determine whether the detection voltage by the detector is the second reference voltage or higher, and the controller is configured to stop an operation of the voltage converter when the detection voltage by the detector is determined to be the second reference voltage or higher through the determination unit.