A conventional lighting system is coupled to an alternating current (AC) power source, and includes a plurality of lamps. Each of the lamps includes a light emitting diode (LED) unit, and a power converting device that is coupled between the AC power source and the LED unit, and that converts an AC input voltage from the AC power source into a direct current (DC) output voltage for powering the LED unit.
For the conventional lighting system, a total number of the power converting devices increases with increasing total number of the lamps, and greater total number of the power converting devices leads to higher manufacturing cost and higher power consumption of the conventional lighting system. Moreover, for each of the lamps, heat generated during operation of the power converting device increases internal temperature of the lamp and reduces service life of the LED unit.