US Patent 7224617 Nonvolatile semiconductor memory

A nonvolatile semiconductor memory according to an example of the present invention comprises an internal circuit which writes, erases or reads in one of a high-speed operation mode in which a peak of current consumption takes a first value and a low current consumption mode having a second value lower than the first value, and a mode switch control circuit which controls a switchover between the high-speed operation mode and the low current consumption mode.