APPARATUS FOR EVALUATING AC VOLTAGE OR AC CURRENT SIGNAL

摘要

PROBLEM TO BE SOLVED: To enable a reliable signal evaluation by allowing both limit values to be changed when an AC voltage or a current signal to be evaluated reaches an upper or lower limit value of a window comparator. SOLUTION: Input AC voltage UE is compared with an upper limit value UOS and a lower limit value UUS by comparators V1 , V2 , and when the voltage is within a window region the window comparators send out a STOP signal to shut a block SN to followingly control the voltage. If the voltage exceeds the upper limit value UOS or the voltage is less than the lower limit value UUS, the window comparators send out an UP signal and a DOWN signal respectively. The UP and DOWN signals respectively follow to control the voltage so as to raise or lower the voltage to have both limit values UOS, UUS raised or lowered. A rectangular signal is output from a clock output side TA of the block SN, and final information on the number of rotations is obtained from the level and supplied to an internal combustion engine controller or the like to allow an adjustment mode to be determined.