THERMAL HEAD DEFECT DETECTIVE SYSTEM

摘要

A defect detection system of a thermal element comprises a power supply line (4) for supplying the power source (5) to the thermal element (1), a converting switch (7) for switching the printing power source and a power source to detect a defect, and a comparator (9) for detecting the defect of the thermal element by comparing the voltage drop generated by selecting the power source to detect a defect with the reference voltage.