Patent ID: 8638043

Claim:
A light-emitting diode (LED) lighting device, comprising: a luminescent device configured to provide light according to a first current; a two-terminal current controller coupled in parallel with the luminescent device and configured to regulate the first current according to a voltage established across the luminescent device, wherein: during a rising period of a rectified alternative-current (AC) voltage when the voltage established across the luminescent device does not exceed a first voltage, the two-terminal current controller operates in a first mode; during the rising period when the voltage established across the luminescent device exceeds the first voltage but does not exceed a second voltage, the two-terminal current controller operates in a second mode; during the rising period when the voltage established across the luminescent device exceeds the second voltage, the two-terminal current controller operates in a third mode; and the two-terminal current controller includes: a current limiting unit configured to: conduct a second current associated with the rectified AC voltage, regulate the second current according to the voltage established across the luminescent device and maintain the first current at zero when the two-terminal current controller operates in the first mode; conduct the second current, maintain the second current at a first predetermined value larger than zero and maintain the first current at zero when the two-terminal current controller operates in the second mode; and switch off when the two-terminal current controller operates in the third mode; and an adjusting unit configured to adjust the first predetermined value and the second voltage.