DYNAMIC COLUMN REDUNDANCY DRIVING CIRCUIT

摘要

PROBLEM TO BE SOLVED: To suppress the skew which is produced by detecting the output signal of an address discriminating unit composed of fuses before precharged charge is not sufficiently discharged with a simple construction by a method wherein the output signal is delayed and transmitted to a word driving unit. SOLUTION: An address discriminating unit 420 makes respective bits of which addresses are composed correspond to respective pairs of fuses and cuts off the pairs of fuses selectively in accordance with the respective bit data of defective addresses. A precharging unit 410 precharges a node K with a power supply voltage VCC. If an external address agrees with the defective address, all the N-MOS transistors 421A, 421B, 422A, 422B... provided in a plurality of routes linking the node K with a pull-down transistor 425 are not turned on and hence the node K is kept at the precharged high level. A delaying unit 440 transmits the output of the node K to a driving unit 430 a certain period later.