Abstract: An encryption/decryption device includes a control unit, an encryption/decryption unit and a verification unit. The control unit generates a start text and an encryption/decryption control signal in response to a command signal and one of an input text and an inner text according to an operational mode. The encryption/decryption unit encrypts or decrypts the start text to generate a result text in response to the encryption/decryption control signal. The verification unit provides the result text to the control unit as the inner text and generates an output text and an alarm signal based on the result text and the input text according to the operational mode, where the output text is an encrypted version of the input text or a decrypted version of the input text, and the alarm signal indicates the integrity of the output text.

Abstract: A semiconductor memory device according to some embodiments includes a random converter that receives data and address information including a start address value and an end address value of the address from a central processing unit (CPU), generates and stores at least one random number for each address value from the start address value to the end address value, performs a logical operation on the random number and the data corresponding to the address, and responsively generates randomized data to be stored in memory. Accordingly, the semiconductor memory device randomizes a power consumption signature that can occur when data is stored, thereby writing and reading data in a manner that is resistant to a power attack.

Abstract: A semiconductor memory device according to some embodiments includes a random converter that receives data and address information including a start address value and an end address value of the address from a central processing unit (CPU), generates and stores at least one random number for each address value from the start address value to the end address value, performs a logical operation on the random number and the data corresponding to the address, and responsively generates randomized data to be stored in memory. Accordingly, the semiconductor memory device randomizes a power consumption signature that can occur when data is stored, thereby writing and reading data in a manner that is resistant to a power attack.