| 摘要 |
PURPOSE: A nonvolatile semiconductor memory is provided, which has 1st access time of a multivalued memory as much as an access time of a two-valued flash memory. CONSTITUTION: A sub data circuit(REGRq) has five data storing units(DS1,DS2,DS3,DS4,DS5). Data storing units(DS1,DS2) are constituted with depletion type N channel MOS capacitors(C1,C2). The data storing unit(DS1) has read/write data. The data storing unit(DS3) comprises a latch circuit which is a cross couple flip flop circuit whose power supply is controlled by control signals(SEN,SEN'). The data storing unit(DS4) is constituted with a cross couple flip flop circuit whose power supply is controlled by control signals(LAT1,LAT1'). The data storing unit(DS5) is constituted with a cross couple flip flop circuit whose power supply is controlled by control signals(LAT2,LAT2'). |
