LED emitting device and driving method thereof

摘要

The present invention relates to an LED emitting device and a driving method thereof. The LED emitting device receives an input voltage and supplies a power supply voltage needed for operating an LED channel according to a switching operation of a power switch. The LED emitting device controls the power supply and also controls a load switch between the LED channel and an output voltage. The LED emitting device determines the LED channel to be short circuited when the output voltage is reduced to a predetermined threshold voltage during a predetermined short circuit sense period starting from the time when the output voltage reaches a regulated voltage before the LED channel is dimmed. During the short circuit sense period, the power supply is stopped and the load switch is turned on.

主权项

1. An LED emitting device comprising:
an LED channel; a power supply for receiving an input voltage and supplying an output voltage needed for an operation of the LED channel according to a switching operation of a power switch; a power controller for controlling the power supply; a load switch connected between the LED channel and the output voltage; and a short circuit sense protector for determining the LED channel to be short circuited when the output voltage is reduced to a predetermined threshold voltage for a predetermined short circuit sense period from a time when the output voltage reaches a regulated voltage before the LED channel is dimmed, wherein during the short circuit sense period, the power controller stops the power supply by stopping the switching operation of the power switch and the short circuit sense protector turns on the load switch.