The LE25S40FD is a SPI bus flash memory device with a 4M bit (512K x 8-bit) configuration. It uses a single 1.8V power supply. While making the most of the features inherent to a serial flash memory device, the LE25S40FD is housed in an 8-pin ultra-miniature package. All these featuresmake this device ideally suited to storing program in applications such as portable information devices, which are required to have increasingly more compact dimensions. The LE25S40FD also has a small sector erase capability which makes the device ideal for storing parameters or data that have fewer rewrite cycles and conventional EEPROMs cannot handle due to insufficient capacity.

• Read/write operations enabled by single 1.8V power supply :
• 1.65 to 1.95V supply voltage range
• Operating frequency : 40MHz
• Temperature range : -40 to 85°C
• Serial interface : SPI mode 0, mode 3 supported
• Sector size : 4K bytes/small sector, 64K bytes/sector
• Small sector erase, sector erase, chip erase functions
• Page program function (256 bytes / page)
• Block protect function
• Highly reliable read/write
• Number of rewrite times : 100,000 times
• Small sector erase time : 40ms (typ), 150ms (max)
• Sector erase time : 80ms (typ), 250ms (max)
• Chip erase time : 300ms (typ), 3.0s (max)
• Page program time : 6.0ms/256 bytes (typ), 8.0ms/256 bytes (max)
• Status functions : Ready/busy information, protect information
• Data retention period : 20 years