Detector, a wafer and an electronic device

PROBLEM TO BE SOLVED: To detect process variations of a plurality of comparators at high speed with high precision.SOLUTION: A detection device detects process variations of a plurality of comparators for outputting a comparison result obtained by comparing a signal level of an input signal with a reference level. The detection device includes: a signal input portion for inputting a common input signal and a common reference level in the plurality of comparators, and sequentially changing the signal level of the input signal; and a detecting portion for detecting a number of comparison results indicating a predetermined result among the comparison results of the plurality of comparators about each signal level, and detecting the process variations on the basis of a distribution of a number of the comparison results.