Abstract: A lighting apparatus includes a control circuit configured to control a power supply circuit such that a measurement value of an output current measured by a current measuring device approaches a target value. The control circuit is configured to execute a control mode alternatively selected from the plurality of control modes to control the power supply circuit. The plurality of control modes of the control circuit includes at least a first control mode and a second control mode. The first control mode is a control mode of adjusting the target value in accordance with a first direct-current voltage. The second control mode is a control mode which includes adjusting the target value regardless of the first direct-current voltage.

Abstract: A lighting apparatus includes a step-up converter, at least one step-down converter, and a controller. The step-up converter is configured to step up a voltage of a direct-current power supply to obtain an output voltage having a first voltage value and output the output voltage. The at least one step-down converter is configured to step down the output voltage of the step-up converter to have a second voltage value to output a current having a current value according to the second voltage value to a light source. The controller is configured to acquire information about a specification of the light source, control the step-down converter such that the current value becomes a current value according to the specification, and control the step-up converter such that the first voltage value changes in accordance with the specification.

Abstract: A lighting apparatus includes a control circuit configured to control a power supply circuit such that a measurement value of an output current measured by a current measuring device approaches a target value. The control circuit is configured to execute a control mode alternatively selected from the plurality of control modes to control the power supply circuit. The plurality of control modes of the control circuit includes at least a first control mode and a second control mode. The first control mode is a control mode of adjusting the target value in accordance with a first direct-current voltage. The second control mode is a control mode which includes adjusting the target value regardless of the first direct-current voltage.