| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an NAND type mask ROM in which erroneous data is prevented from being read out. SOLUTION: The NAND type mask ROM comprises a first transistor TR1 connected with a plus power supply VDD, a second transistor TR2 connected with a minus power supply VSS, a plurality of memory transistors T1-Tn connected in series between the first and second transistors TR1, TR2 and also connected with the first transistor TR1, and a bit line BL for reading out data from the memory transistors T1-Tn. A pull-up transistor TR3 is connected between the plus power supply VDD and the bit line BL in order to suppress voltage drop of bit line at the time of reading out the data.</p> |
