A semiconductor apparatus includes a plurality of stacked chips. Each of the plurality of stacked chips includes a delay chain. Each of the plurality of stacked chips comprises a plurality of Through-Vias, wherein one of the plurality of Through-Vias formed in a first one of the plurality of stacked chips and electrically coupled to a predetermined location of a first delay chain on the first one of the plurality of stacked chips and one of the plurality of Through-Vias formed in a neighboring one of the plurality of stacked chips and electrically coupled to a predetermined location of a delay chain on the neighboring one of the plurality of stacked chips are configured to electrically couple the first one of the plurality of stacked chips to the neighboring one of the plurality of stacked chips. A signal transmitted from a first one of the plurality of stacked chips generates a feedback signal to the first one of the plurality of stacked chips through one or more of the plurality of Through-Vias.