Ac led lighting apparatus using voltage edge detector

An AC LED lighting apparatus, comprising:

• a rectification unit configured to rectify an AC voltage to output a DC rectified voltage;
• an LED unit comprising a first light emitting group and a second light emitting group each including at least one LED;
• and
• an LED driving control unit comprising:
• a voltage edge detector configured to detect a slope of a currently input rectified voltage, and output a second control signal corresponding to the detected slope of the rectified voltage to a control logic;
• a reference voltage generator configured to generate a reference voltage according to a reference voltage setting signal output from the control logic;
• and
• a comparator configured to compare a voltage level of a set reference voltage with a voltage level of the currently input rectified voltage and output a first control signal corresponding to a comparison result to the control logic,
• wherein the control logic is configured to control a serial/parallel connection relationship between the first light emitting group and the second light emitting group by detecting the first control signal and the second control signal input from the comparator, and output the reference voltage setting signal,
• wherein the LED driving control unit is configured to control a serial/parallel connection relationship between the first light emitting group and the second light emitting group by comparing a voltage level of the rectified voltage input from the rectification unit with a reference voltage, and
• wherein the LED driving control unit sets the reference voltage by detecting a slope of the rectified voltage and simultaneously detecting the voltage level of the rectified voltage and the detected slope of the rectified voltage.