Patent ID: 6147486
Filing Date: 2000-11-14
Classification: F02D

Abstract:
A device for analyzing an alternating voltage or current signal that includes a variable D. C. voltage or D. C. current component, said device comprising:a window comparator including means for comparing the alternating voltage or current signal to an upper threshold and a lower threshold; andmeans for adjusting said upper threshold and said lower threshold when one of the upper and the lower thresholds is reached by the alternating voltage or current signal;wherein said means for adjusting said upper and lower thresholds comprises a threshold adjustment circuit portion, said window comparator includes means for generating control signals for said threshold adjustment circuit portion and said threshold adjustment circuit portion is connected to said window comparator to receive said control signals therefrom;wherein the threshold adjustment circuit portion includes a counter holding a count and means for converting said count into an auxiliary voltage and for setting the upper threshold and the lower threshold of the window comparator according to the auxiliary voltage; andwherein the control signals from the window comparator include up-count signals, stop signals and down-count signals that activate the counter to count up, that maintain the count and that activate the counter to count down respectively.