EEPROM(also E2PROM) stands for electrically erasable programmable read-only memory) is the latest trend in RAM technology, where data retains when power supply switched off,We know traditional RAM are volatile memory they can't retain data after a power failure,EEPROM traditionally used in microcontrollers,smart cards,remote keyless system,where RAM needs are limited and individual Bytes to be programmable and eraed,which is revolutionary in modern day Ram technology where we can use it as an alternative to traditional DRAM,Significantly reduces today's computer booting time
EEPROMs are organized as arrays of floating-gate transistors.EEPROM can be programmed and erased in circuite using special programming codes,traditionally EEPROM could only represent one byte at time limited read and write cycles,,But advanced research in EEPROM for using as an alternative for RAM made it much capable than earlier,modern day EEPROM could make millions of read and write operation while working.Unlike traditional non volatile memory where data can't be represented in single bytes rather block of data that erased wholly, but in EEPROM could allows data to be written in a single Byte (or a word)Revolutionary in terms of RAM technology.
Nowadays, EEPROM is used for embedded microcontrollers as well as standard EEPROM products. EEPROM still requires 2 transistors structure per bit to erase a dedicated byte in the memory, while flash memory has 1 transistor per bit to erase a region of the memory.
EEPROM memory is used to enable features in other types of products that are not strictly memory products. Products such as real-time clocks, digital potentiometers, digital temperature sensors, among others, may have small amounts of EEPROM to store calibration information or other data that needs to be available in the event of power loss. It was also used on video game cartridges to save game progress and configurations, before the usage of external and internal flash memories.
Flash memory is a later form of EEPROM. In the industry, there is a convention to reserve the term EEPROM to byte-wise erasable memories compared to block-wise erasable flash memories. EEPROM occupies more die area than flash memory for the same capacity, because each cell usually needs a read, a write, and an erase transistor, while flash memory erase circuits are shared by large blocks of cells (often 512×8).
Newer non-volatile memory technologies such as FeRAM and MRAM are slowly replacing EEPROMs in some applications, but are expected to remain a small fraction of the EEPROM market for the foreseeable future.