Redundancy circuit and method of a semiconductor memory device

Abstract

The present invention provides a redundancy circuit in a semiconductor memory device which has spare memory cells which can store information that can be substituted for data of defective memory cells after the completion of the manufacturing process. If addresses designating the defective memory cells are externally input, the redundancy circuit generates a defective cell relief address signal which corresponds to the address designating the defective memory cell and is used to prevent defective data stored in normal memory cells from being output and causes correction data, to be substituted for the defective data output in correspondence with the defective cell relief address.