| 摘要 |
<p>PURPOSE:To effectively allow device discrimination codes to work even when repairing is executed by writing the data of a device discrimination code in two or more column repair lines beforehand. CONSTITUTION:A device discrimination code storage element 2a is connected to a transistor Tr 1 for the device discrimination code connected to the bit lines B1-Bm of a memory cell array 2. A device discrimination code storage element for repair 20a in which the codes of the same content with the device discrimination code is provided in a redundant circuit 20. When the bit line B1 is defective, the circuit 20 is made to select a column repair line BS1 instead of the line B1 so far selected. As the data of the same device code with a Tr 3 are written in a Tr 5, the data of accurate device code are read out. In a case where the line Bm is defective, by selecting a column repair line BS2 similarly, an accurate maker code is read out since the data of the same maker code with a Tr 4 are written beforehand in a Tr 6.</p> |
