Digital circuit for measuring relative frequency in separate pulse trains

摘要: A digital circuit determines the maximum frequency present in a first pulse train and indicates when selected fraction of this is exceeded subsequent trains. The invention comprises prescaler for purpose reducing input to level suitable period-measuring circuit; period-measurement that measures period output compares measured value stored value; frequency-multiplier produces reference used measure control operate circuits mode storing representative train, second comparing trains with mode. an signal exceeds train.