Light-emitting diode driving device for reducing light off period

Abstract

An LED driving apparatus is provided. The apparatus includes an LED Portion 10, a charging / discharging capacitor 111, a capacitor charging and discharging paths, and a capacitor charging constant current portion 110. The LED driving portion 3 controls a current in the LED portion 10. The capacitor 111 is connected in parallel to the LED portion 10. The charging and discharging paths are connected to the capacitor whereby charging and discharging the capacitor, respectively. The constant current portion 110 is connected on the charging path and controls a charging current so that the capacitor is charged at a constant current. When rectified voltage applied to the LED portion becomes high, the capacitor is charged with the charging current through the charging path. When the voltage becomes low, the capacitor is discharged at a discharging current through the discharging path so that the discharging current is applied to the LED portion.

Description

technical field

[0001] The present invention relates to a driving circuit for driving light-emitting diodes, in particular to a driving device for light-emitting diodes driven by AC power. Background technique

[0002] In recent years, light-emitting diodes (hereinafter also referred to as "LEDs") that can be driven with lower power consumption than incandescent lamps and fluorescent lamps have attracted attention as light sources for illumination. LED has the advantages of small size and high impact resistance, so there is no need to worry about burning out the bulb.

[0003] As such a power source for lighting equipment, it is desired to use an AC power source such as a household power source as a power source. On the other hand, LEDs are DC-driven components that only emit light under forward current. In addition, the forward voltage V of LEDs currently mostly used for lighting purposes f It is about 3.5V. The LED has a V f It will not emit light, otherwise if it exc...

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