| 摘要 |
PURPOSE:To perform the redundant/normal bit switching without using a large amount of current and to improve both integration density and reliability, by using a stacked gate type MIS transistor in place of a polycrystal silicon fuse used to a redundant/normal bit switching circuit. CONSTITUTION:A redundant/normal bit switching circuit contains transistors TRQ24-Q26 provided in series between a writing power supply terminal VPP and an earth, the 1st node N23, and a diode Q27, inverters Q22 and Q23 , a pull-up resistance Q21, level shaping circuits Q2A and Q2B or Q28 and Q29, and transfer gates Q2D and Q2C which are provided between the node N23 and a power supply terminal VCC. Thus it is possible to perform switching between redundant and normal bits without requiring a large amount of current. This improves both integration density and reliability of a semiconductor device. |
