Patent ID: 9126530
Filing Date: 2015-09-08
Classification: B60Q,H05B,Y02B

Abstract:
1. A lighting device, comprising: a power converter configured to convert a first power supply voltage that is received from a DC power supply through a first path, and supply an output obtained by the conversion to a load in which a plurality of light emitting elements are connected in series; a bypass unit configured to short-circuit at least one light emitting element of the plurality of light emitting elements, as part of the load; and a controller configured to control the power converter, the controller being configured to control switching a first state where the at least one light emitting element is short-circuited by the bypass unit, and a second state where the short-circuiting is opened, the controller being configured to perform a first control and a second control, the first control being of: starting operation of the power converter, when the first power supply voltage exceeds a starting voltage; and stopping the operation of the power converter, when the first power supply voltage is below a maintaining voltage that is lower than the starting voltage, the second control being of: switching to the second state, when a second power supply voltage exceeds a first threshold voltage that is lower than the starting voltage, the second power supply voltage being input from the DC power supply through a second path different from the first path; maintaining the second state until the second power supply voltage is below a second threshold voltage that is lower than the first threshold voltage; and switching to the first state, when the second power supply voltage is below the second threshold voltage.