Abstract: A method for preventing redundant events from toggling the core logic during scan data shifting mode is provided. A logic element is controlled by SEL. During scan data shifting mode, no toggled data will interfere with the core logic because the logic element is shut off. Only the scan path (SI-SO-SI) continues toggling. Therefore, redundant events are prevented from toggling the core logic. Therefore the simulation time is reduced and the verification flow is sped up. Additionally, the power consumption during testing is significantly reduced.