Difference between EPROM and EEPROM
EPROM and EEPROM are pretty similar because they have many similarities, such as they both can be erasable and reusable, and both have non-volatile memory, so it is tough to differentiate between them. Before jumping into the distinction between EPROM and EEPROM. Let us know the meaning of EPROM and EEPROM.
EPROM
EPROM is short form Erasable Programmable Read Only Memory. It is a kind of Read Only Memory (ROM). It was developed by Dov Frohman at Intel in 1971.
EPROM memory is non-volatile, and the data on the EPROM chip is not lost once the power supply is turned off. EPROM is an erasable chip, so if you want to erase the data, you can erase and store new data and reuse the chips. The chip is exposed to a strong ultraviolet light source, and the data is erased using an EPROM eraser.
It has a transparent quartz crystal window cover on top of the chip, which makes it easily recognizable. EPROM chips are used in microcontrollers, BIOS of computers, etc.
EEPROM
EEPROM is an abbreviation for Electrically Erasable Programmable Read Only Memory. It is also a type of ROM (Read Only Memory). Eliyahou Harari invented the electrically reprogrammable read-only memory chip at the Hughes Aircraft Company. It was a replacement for EPROM.
The data is retained even after the power supply is cut. EEPROM consists of arrays of floating-gate transistors. Initially, EEPROM chips were slow due to single-byte operations, but modern EEPROM chips are faster due to multi-byte operations. It can be erased and reprogrammed electrically.
It can frequently erase and reprogram the chip without taking much time, but erasing and reprogramming an EEPROM chip has a limited life. It can erase and reprogram the chip about 10,000 times.
It takes about 5 to 10ms to erase and reprogram the chip. It can selectively erase data from the chip, which means one can erase the part of the data you want to delete instead of erasing the entire chip.
It stores small amounts of data in devices like smart cards, computer microcontrollers, etc.
The vital difference between EPROM and EEPROM are as follows:
| EPROM | EEPROM |
| EPROM is the term used for Erasable Programmable Read Only Memory. | EEPROM is the abbreviated form of Electrically Erasable Programmable Read Only Memory. |
| It allows ultraviolet light to enter from the top of a transparent fused quartz window. | It is kept enclosed in an opaque plastic case. |
| Dov Frohman developed EPROM at Intel in 1971. | EPROM was developed by Eliyahou Harari. |
| Strong ultraviolet light is used to erase data from EPROMs. | An electric signal is used to erase data from EEPROMs. |
| It is a previous version of EEPROM. | It is a new version of EPROM. |
| The chip should be taken out from the computer to erase and reprogram data. | Removing the chip from the computer is not required to erase the data and reprogram it. |
| It is one time programmable (OTP). | It can be reprogrammed over and over again. |
| It can store an enormous amount of data as compared to EEPROM. | It can store less amount of data in comparison to EPROM. |
| It is less expensive than EEPROM. | It is more expensive than EPROM. |
| It takes several minutes to erase and reprogram the data from the EPROMs. | It takes 5 to 10 milliseconds to erase and reprogram the data from EEPROM. |
| When erasing data, the entire data is erased from the chip. | When erasing data, parts of the data may be erased from the chip. |
We conclude that the main difference between EPROM and EEPROM is that the EPROM is erased with the help of ultraviolet light, i.e., optically. In contrast, EEPROM is erased with the help of an electrical signal, i.e., electrically. The table above demonstrates the difference between EPROM and EEPROM.