Abstract: An integrated circuit (IC) device is provided. The IC device includes a detector configured to detect an abnormal condition of the IC device and to generate a detection result as an attack signal, and a noise filter configured to filter out the attack signal as noise and to generate a filtered attack signal. The noise filter is configured to filter out the attack signal as noise when the attack signal is not maintained at a first logic level for a reference period and to generate the filtered attack signal when the attack signal is maintained at the first logic level for the reference period.