Patent attributes
A redundancy circuit can include a first fuse set that is configured to receive an address signal and an initializing signal activated when power is up, and to output a first redundancy signal, the first redundancy signal being used to repair a defective cell by using a laser beam radiating method, a second fuse set that is configured to receive the initializing signal, a specific address signal, a test mode signal that is activated when a defective cell exists, and the address signal, and to output a second redundancy signal, the second redundancy signal being used to repair the defective cell by using an electrical fusing method, a first memory cell array that is controlled by the first redundancy signal, and a second memory cell array that is controlled by the second redundancy signal.