Patent ID: 7095652
Filing Date: 2006-08-22
Classification: G11C

Abstract:
1. A semiconductor storage device comprising: memory cells that store data by accumulating or releasing an electric charge; a memory cell array having a matrix arrangement of the memory cells; a plurality of word lines connected to memory cells aligned on rows of the memory cell array; a plurality of sub-bit lines connected to memory cells aligned on columns of the memory cell array; a bit line select circuit selecting the sub-bit line of a column; a main bit line connected to the sub-bit line selected by the bit line select circuit; a sense line detecting the potential of the sub-bit line selected by the bit line select circuit via the main bit line and reading data out of the memory cell; a write driver applying a voltage to the sub-bit line selected by the bit line select circuit via the main bit line and writing data into the memory cell; and a first switching element connected to the main bit line and turning on when the current flowing in the memory cell is detected externally via the sub-bit line without the use of the sense line or when a voltage is applied to the memory cell externally via the sub-bit line without the use of the write driver.