| 摘要 |
PURPOSE:To monitor the defects of an analog input circuit by extracting only a data related to a signal for monitor from a signal, on which the signal for monitor having frequency different from the system input and the system input are overlapped. CONSTITUTION:A signal Eref for monitor is generated by a signal circuit 23 for monitor, and applied at all times in a shape that the signal Eref is overlapped to PCT inputs 21 by filters 24. Consequently, the signal Eref for monitor overlapped is converted into a digital value by an A/D converter 12 through the filters 24, sample-and-hold sections 25 and a multiplexer 26. A digital processing section 9 extracts only a signal Eref component for monitor from a digital data, and computes the magnitude of the signal for monitor from a sampling data. The defects of the A/D converter 12 can be detected from the filters 24 from the magnitude of the signal for monitor computed. |
