Abstract:
A method of manufacturing a power supply unit (PSU) is provided. The method includes providing at least one PSU supplying a dimming signal to at least one light source, performing a first test for electrical characteristics of the at least one PSU, detecting light emitted from the at least one light source, measuring a flicker of the at least one light source, and performing a second test for a state of the at least one PSU based on a flicker measurement result, and packing a PSU determined to be in a normal state among the at least one PSU, as a result of the first test and the second test.
Abstract:
A light emitting diode driving apparatus includes a rectifier, a converter, a feedback circuit, and a controller. The rectifier converts alternating current power to direct current (DC) power. The converter supplies driving power to a plurality of LEDs based on the DC power. The feedback circuit generates a feedback signal based on a current flowing in the plurality of LEDs and adjusts a magnitude of the feedback signal. The controller changes a maximum value of a current output by the converter based on the adjusted magnitude of the feedback signal.
Abstract:
A light emitting device includes a light source unit, a connection controller, and a driving controller. The light source unit includes a first LED array including a plurality of first LEDs connected in series and a second LED array including a plurality of second LEDs connected in series. The connection controller selectively sets a connection structure between the first and second LED arrays as a series connection, a parallel connection, or a series-parallel connection based on a peak value of a driving voltage driving the light source unit. The driving controller controls the number of LEDs driven in the light source unit according to a magnitude of the driving voltage. Each of the first and second LED arrays is connected between a plurality of first nodes and a plurality of second nodes.
Abstract:
A light emitting diode (LED) driving device is provided. The LED driving device includes a rectifier configured to rectify alternating current (AC) power to generate rectified power; an AC driver configured to control operations of a plurality of LED groups so that the plurality of LED groups receive the rectified power generated by the rectifier; and a light amount controller configured to reduce an amount of current applied to the plurality of LED groups when a peak value of the rectified power is increased, and increase the amount of current applied to the plurality of LED groups when the peak value of the rectified power is reduced.