This application note provides library source code in C for the M29F040 and the M29W040 Flash memories. The M29W040, with a rated power supply of 3V, is a low voltage version of the M29F040 whose power supply is rated at 5V. The M29W040 has slightly slower access times than the M29F040, but the two devices are otherwise very similar. This application note supports both devices and all technical information about the M29F040 also applies to the M29W040, except where otherwise specified.