POWER VOLTAGE ABNORMALITY DETECTOR FOR MULTI-SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To verify and warn the occurrence of power voltage abnormality for every substrate and to improve the maintenance effect in detail way by retrieving the presence or absence of a substrate that has the power voltage abnormality in an error detection process and performing the reading of the power voltage value and the comparison of data. SOLUTION: The resistances 1 to 4 of a circuit A prescribe the upper and lower thresholds of a desired optional voltage level to be monitored. If the power voltage gets out of its prescribed range, the output signal of one of comparators 5 and 6 is inverted. Then the output signal of a flip-flop circuit 8 is inverted and inputted to an I/O 14 as a signal that shows a substrate having the voltage abnormality. At the same time, the power voltage value that is converted into the digital data is automatically held by a latch circuit 10. A circuit B is mounted on a main substrate to check the power voltage and to hold the data and has the same basic operation as the circuit A. A circuit C identifies a substrate having the power voltage abnormality on the main substrate and performs the reading of the abnormal voltage value and the display of a warning.