A regular sense amplifier and a defect-information sense amplifier are
provided for each regular sector and each defect-information sector,
respectively. This can prevent an excess load from being applied to a
read path, and minimize the access time. A write amplifier is provided in
common to the regular sector, the reference sector, and the
defect-information sector. Generally, the write operation time of a
nonvolatile semiconductor memory is long, so that an increase in a wiring
load on a data transmission path and an increase in a load on a switch do
not affect the write operation time much. As a result, the circuit scale
can be made smaller without lengthening the read access time, and thereby
the fabrication cost of the nonvolatile semiconductor memory can be
reduced.