# US 2017/0290118 A1 · Light-emitting element driving device, light-emitting device, and vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0290118 A1 - Document ID: US20170290118A1 - Status: Published application - Kind: A1 - Application number: 15/512,341 - Filed: 2015-09-03 - Published: 2017-10-05 - Earliest claimed: 2014-10-02 - Assignees: Rohm Co., Ltd. - Applicants: Rohm Co., Ltd. - Inventors: Shinsuke TAKAGIMOTO - Web page: https://patentgrep.com/patent/US20170290118A1 ## CPC - H05B 45/37: Converter circuits - B60Q 1/00: Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor (for lighting vehicle interior B60Q3/00) - B60Q 1/1415: {Dimming circuits} - B60Q 11/00: Arrangement of monitoring devices for devices provided for in groups B60Q1/00 - B60Q9/00 - H05B 45/10: Controlling the intensity of the light - H05B 47/20: Responsive to malfunctions or to light source life; for protection - H10H 20/80: Constructional details - B60Q 1/04: the devices being headlights - B60Q 1/34: for indicating change of drive direction (B60Q1/22 takes precedence) - B60Q 1/44: for indicating braking action {or preparation for braking, e.g. by detection of the foot approaching the brake pedal} - B60Q 2400/30: Daytime running lights [DRL], e.g. circuits or arrangements therefor - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - B60Q: ARRANGEMENT OF SIGNALLING OR LIGHTING DEVICES, THE MOUNTING OR SUPPORTING THEREOF OR CIRCUITS THEREFOR, FOR VEHICLES IN GENERAL - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract A light emitting drive device has an output voltage supply unit, and an emergency drive unit. The output voltage supply unit generates an output voltage from an input voltage on the basis of a control signal transmitted from a control unit, and supplies at least one light emitting element with the output voltage. In the cases where the emergency drive unit received a signal indicating abnormality of the control unit, the emergency drive unit lights the whole or a part of the at least one light emitting element irrespective of the control signal transmitted from the control unit. ## Claims ### Claim 1 A light-emitting element driving device comprising: an output voltage feeder configured to generate an output voltage from an input voltage based on a control signal from a controller to feed the output voltage to at least one light-emitting element; and an emergency driver configured to turn ON all or part of the at least one light-emitting element irrespective of the control signal from the controller on receiving a signal indicating a fault in the controller. ### Claim 2 (depends on 1) The light-emitting element driving device of claim 1, wherein a value of a current that the emergency driver outputs to all or the part of the at least one light-emitting element is smaller than a value of a current that the output voltage feeder outputs to the at least one light-emitting element. ### Claim 3 (depends on 1) The light-emitting element driving device of claim 1, wherein the output voltage feeder and the emergency driver share between them a high-side transistor and a low-side transistor connected between a terminal to which the input voltage is applied and a ground terminal, a connection node between the high-side and low-side transistors being connected via a coil to an output capacitor, a high-side driver and a low-side driver configured to generate drive control signals for the high-side and low-side transistors respectively, an amplifier configured to generate a feedback voltage commensurate with a current through the at least one light-emitting element, and a driver controller configured to drive the high-side and low-side drivers so as to turn the high-side and low-side transistors ON and OFF according to the feedback voltage, and the high-side and low-side transistors, the high-side and low-side drivers, the amplifier, and the driver controller are all integrated in a single semiconductor device. ### Claim 4 (depends on 3) The light-emitting element driving device of claim 3, wherein the emergency driver includes a selector configured to select and output the control signal when no signal indicating a fault in the controller is received and to select and output a constant voltage when a signal indicating a fault in the controller is received, and the driver controller is configured to switch whether or not to drive the high-side and low-side drivers according to an output of the selector. ### Claim 5 (depends on 4) The light-emitting element driving device of claim 4, wherein the selector is integrated in the single semiconductor device. ### Claim 6 (depends on 1) A light-emitting device comprising: a light-emitting element driving device of claim 1; at least one light-emitting element configured to be driven by the light-emitting element driving device; a controller configured to feed a control signal to the light-emitting element driving device; and a monitor configured to monitor the controller to transmit, on detecting a fault in the controller, a signal indicating the fault in the controller to the light-emitting element driving device. ### Claim 7 (depends on 6) The light-emitting device of claim 6, wherein the light-emitting element is a light-emitting diode or an organic EL element. ### Claim 8 (depends on 7) The light-emitting device of claim 7, wherein the light-emitting device is used as a vehicle-mounted lamp. ### Claim 9 (depends on 8) The light-emitting device of claim 8, wherein the light-emitting device is mounted as a head light module, a turn lamp module, or a rear lamp module on a vehicle. ### Claim 10 (depends on 8) A vehicle comprising the light-emitting device of claim 8. ### Claim 11 (depends on 10) The vehicle of claim 10, wherein the light-emitting device is used as one of a head light, a light source for a daytime running light, a tail lamp, a stop lamp, and a turn lamp.