COLUMN REPAIR CIRCUIT OF SEMICONDUCTOR MEMORY DEVICE

摘要

PURPOSE: A column repair circuit of semiconductor memory device is provided to reduce an occupied area of semiconductor memory device due to providing a repair circuit by repairing a wrong bit line without increasing in a fuse array block. CONSTITUTION: A cell block(20) has a column cell array transferring data into a bit line when a particular word line is activated. A redundant column block(21) has an additional column cell array to substitute for the bit line of the cell block when it is disordered. An input/output line decoder(23) generates a selecting signal for selecting either a normal bit line or a redundant bit line compared with a stored bit line information when the information of the disordered bit line is stored in the ROM form to input Y selecting information from the external. An input/output coding block(24) makes the redundant bit line within the redundant column block and the normal bit line of the disordered bit line to be replaced to the input/output line in order to substitute only the input/output line connected the bit line on repairing. A Y address pre-decoder(25) supplies signals to a Y address decoder for activating the normal bit line and redundant bit line so that a Y address signal is received to make an access from the external to select a particular bit line.