Patent ID: 7359274

Claim:
A semiconductor memory device comprising: a memory cell array having a plurality of data select lines disposed in parallel with each other, a plurality of data transfer lines disposed in parallel with each other to intersect said data select lines, and electrically rewritable non-volatile memory cells laid out at cross portions between said data select lines and data transfer lines; a data select line driver for driving said data select lines of said memory cell array; a sense amplifier circuit connected to said data transfer lines of said memory cell array, for performing data read of memory cells selected by one of said data select lines; and a control circuit used for timing control of data read of said memory cell array, for outputting at least two types of timing signals, wherein said device has a data write mode for writing data into selected memory cells, said data write mode including a verify-read operation for verifying a write state, said memory cell array is divided into at least one first area and at least one second area in the direction of said data select lines in such a way that these areas are simultaneously selected by one of said data select lines, said control circuit has a first timing circuit for outputting a timing signal necessary for performing data read of said first and second areas simultaneously selected by one of said data select lines within a first cycle time and a second timing circuit for outputting a timing signal necessary for performing data read of at least said second area within a second cycle time shorter than said first cycle time, said data select line driver is disposed at an end portion of said data select lines in close proximity to said second area, and each of said first and second areas in said memory cell array includes a NAND type cell unit including a plurality of said memory cells connected in series and a select gate transistor connected to said data transfer line, the number of said memory cells in said NAND cell unit in said first area being equal to that in said second area.