Programmable memory data protection scheme

摘要

An integrated, non-volatile memory protect register is provided for the memory array of a monolithic integrated circuit device. The memory array includes a plurality of programmable data storage registers, each having an associated address. The storage register addresses define the storage registers sequentially from an initial register in the array to a final register in the array. The memory protect register stores the address of a preselected storage register in the array. All registers in the array having addresses equal to or greater than the address of the preselected register are protected from any write operation. This address can be "locked" into the memory protect register to provide permanent data security to all protected registers.