Current-limiting device and light-emitting diode apparatus containing the same

An LED apparatus;

• comprising:
• an LED component corresponding to a current-limiting resistance value and comprising at least one LED of a forward voltage and an operating current;
• and
• a current-limiting device comprising a plurality of positive temperature coefficient devices merely connected in series, the positive temperature coefficient devices being capable of sensing temperature of the LED and electrically coupled to the LED component;
• wherein a resistance value of the current-limiting device increases with increasing sensed temperature, the resistance value of the current-limiting device at an LED normal operating temperature is close to or equal to the current-limiting resistance value;
• when the temperature of the LED gradually increases to an abnormal temperature, current allowable to be flowed through the current-limiting device gradually decreases to be lower than the operating current, wherein the plurality of positive temperature coefficient devices have yet to reach a trip temperature thereof when the at least one LED increases to the abnormal temperature.