The IS25LD040 are 4Mbit Serial Peripheral Interface （SPI） Flash memories， providing single- or dual-output. The devices are designed to support a 33 MHz clock rate in normal read mode， and 100 MHz in fast read， the fastest in the industry. The devices use a single low voltage power supply， wide operating voltage ranging from 2.30 Volt to 3.60 Volt， to perform read， erase and program operations. The devices can be programmed in standard EPROM programmers. The IS25LD040 are accessed through a 4-wire SPI Interface consisting of Serial Data Input/Output （SlO）， Serial Data Output （SO）， Serial Clock （SCK）， and Chip Enable （CE#） pins. They comply with all recognized command codes and operations. The dual-output fast read operation provides and effective serial data rate of 200MHz. The devices support page program mode， where 1 to 256 bytes data can be programmed into the memory in one program operation. These devices are divided into uniform 4 KByte sectors or uniform 64 KByte blocks. The IS25LD040 are manufactured on pFLASH?’s advanced non-volatile technology. The devices are offered in 8-pin 208mil SOIC， 8-pin SOIC 150mil， 8-pin VVSOP 150mil， and 8-pin WSON 。 The devices operate at wide temperatures between -40°C to +105°C.