Circuit for removing noise form power line and semiconductor memory device having the circuit

摘要

The power noise removing circuit includes a decoupling capacitor group, a repair circuit unit, a monitoring pad, and a testing unit. The decoupling capacitor group includes a plurality of decoupling capacitors that store noise flowing into an internal power line. The decoupling capacitors are DRAM cell type capacitors. The repair circuit unit controls a connection of each of the decoupling capacitors in the decoupling capacitor group to an external input power line. The monitoring pad measures the amount of current leaking from the decoupling capacitor group. The testing unit controls a connection of the decoupling capacitor group to the monitoring pad. If the decoupling capacitor group is tested as being defective, the defective decoupling capacitor group is made inoperative by disconnection from the external input power line.