 FRAM or MRAM could potentially replace it as it is denser which would make it more cost effective.In addition to the SRAM, some microcontrollers also have internal EEPROM for data storage; and even ones that do not have any (or not enough) are often connected to external serial EEPROM chip (such as the BASIC Stamp) or external serial flash memory chip.A few recent microcontrollers beginning in 2003 have "self-programmable" flash memory.