Soldering apparatus processor having temperature selection, calibration and heating control of tip

摘要

A soldering system is disclosed having a stored program microcontroller by which one or more temperatures can be selected for a soldering iron tip. The system then automatically maintains such tip temperature during the soldering operation. The programmed microcontroller is coupled through input/output and interface circuits to a heating control that in turn is connected to the iron heater element for switching AC power in units of full waveform cycles across the element while the temperature of the tip is measured by a resistor sensor and an associated bridge measurement circuit so as to produce a signal that is applied to an input of the microcontroller forming a feedback loop. This causes the resistor sensor and hence the iron tip to reach the desired temperature. A thermocouple is provided for measuring and calibrating the actual temperature of the iron tip thus ensuring that the resistor sensor and associated feedback loop causes the microprocessor to drive the heater element as needed to cause the soldering tip to stabilize at the selected temperature. The external thermocouple probe may also be used separately and simultaneously with the soldering operation to ensure that the temperature of a probed component does not exceed a predetermined safe level.