Microchip's AT25128B-SSHL-T is an electrically erasable programmable read-only memory (EEPROM) chip used for non-volatile storage of data. It has a 128K density, meaning that it can store up to 128 kilobits of data. It has a SPI 16,384 x 8 organization, meaning that it has 16,384 individual memory cells, each one 8 bits in size. It can be externally erased in blocks as small as 256 bytes when connected to suitable voltage sources. The chip also has several features aimed at improving reliability, including protection against low and high supply voltages, multiple write cycles and data retention of up to 100 years.