Patent ID: 8698416
Filing Date: 2014-04-15
Classification: H05B,Y02B

Abstract:
1. A continuous dimming AC LED device, comprising: a rectifier for converting AC sinusoidal power into DC sinusoidal power and outputting the DC sinusoidal power from an anode and a cathode of the rectifier; a low-voltage DC power generator having a power input terminal, a ground terminal and a power output terminal, wherein the power input terminal is connected to the anode of the rectifier and the ground terminal is connected to the cathode of the rectifier; an LED unit having a first power terminal and a second power terminal, wherein the first power terminal is connected to the anode of the rectifier; a voltage-controlled switch connected between the second power terminal of the LED unit and the cathode of the rectifier and having a control terminal; a current detector connected between the voltage-controlled switch and the cathode of the rectifier and having an output terminal; a switch having a first contact, a second contact, a common point and a control terminal, wherein the first contact is connected in series with a resistor and then to the anode of the rectifier, and the common point is connected to the control terminal of the voltage-controlled switch; a control unit comprising a voltage detection terminal, an output terminal and a voltage detection unit, wherein the voltage detection unit is connected to the anode of the rectifier via the voltage detection terminal, and the output terminal is connected to the control terminal of the switch; and an AC LED driver having two power input terminals, an output terminal, and an input terminal, wherein the two power input terminals are electrically connected to the power output terminal and ground terminal of the low-voltage DC power generator, the output terminal of the AC LED driver is connected to the second contact of the switch, and the input terminal of the AC LED driver is connected to the output terminal of the current detector; wherein the common point of the switch is connected to the output terminal of the AC LED driver via the second contact of the switch when a supply voltage applied to the AC LED driver is higher than a limit voltage, and the common point of the switch is alternatively connected to the anode of the rectifier via the first contact when the supply voltage applied to the AC LED driver is lower than the limit voltage.