TCO RESISTOR PROTECTION CIRCUIT OF CRT

摘要

PURPOSE: A TCO resistor protection circuit of a CRT is provided to sense instantaneous overcurrent flowing in a TCO resistor(Rtcc) to turn a system power supply off. CONSTITUTION: The CRT generates a TCO signal having a phase opposite to a phase of a horizontal pulse signal to supply it to a TCO sensor through a TCO resistor(Rtcc), thereby offsetting harmful electromagnetic wave irradiated from a front of the CRT. An overcurrent sensing part(24) senses instantaneous overcurrent flowing in the TCO resistor(Rtcc) to output an overcurrent sensing signal. A microcomputer turns a power supply(50) off by controlling the power supply if the overcurrent sensing signal is input. The overcurrent sensing part(24) consists of a DC converter(25) and a comparator(26).