Patent ID: 6946623

Claim:
A solder heating appliance with adjustable duty cycle comprising: a body portion; at least one electrical heating element associated with the body portion, the at least one electrical heating element for radiating heat to the solder; a power source electrically coupled to the at least one electrical heating element, wherein the power source provides power to the at least one electrical heating element; a sensor for sensing the at least one electrical heating element temperature and generating a corresponding signal; a comparator circuit for comparing a reference signal to the sensor generated corresponding signal and generating a first output signal only until a comparison is made and only then ceasing to generate the first output signal and generating a second output signal; and a pulsing circuit, including a power transistor electrically coupled between the power source and the at least one electrical heating element, the power transistor further having a trigger electrically coupled to the comparator for receiving the first output signal, wherein the power transistor provides continuous power to the at least one electrical heating element only as long as the first output signal from the comparator is received at the trigger.