In writing N level of multilevel data to nonvolatile semiconductor memory by repeating a verification process, a verification result of a memory cell where the Nth threshold level which is the highest level is to be written as an expected level is invalidated until completion of writing to a memory cell where the (N-1)th and lower level is to be written. The verification result of the memory cell where the Nth level is to be written is validated after reaching the (N-1)th write level. A reference current supplied to a sense amplifier corresponding to the Nth level is set at at least a level allowing no indeterminate sensing of a sense amplifier. In verification of the Nth level data, a word line voltage supplied for verify-reading is raised from VW 1 to VW 2.

 
Web www.patentalert.com

< Nuisance alarm reductions in a physiological monitor

< Universal modulator

> Set-top box with out-of band modem and cable modem

> Semiconductor memory device performing reliable data sensing

~ 00204