Difference Between EPROM and EEPROM


Both EPROM and EEPROM are the types of ROM or Read Only Memory, but they are different from each other in many aspects that we will discuss in this article. Let's start with some basics of EPROM and EEPROM so that it becomes easier to understand the differences between them.

What is EPROM?

EPROM stands for Erasable Programmable Read Only Memory. EPROM is a modern version PROM (or Programmable Read Only Memory). EPROM provides the facility of erasing data stored on it. It uses ultraviolet rays (UV rays) to erase the content stored it.

EPROM is built up of MOS (Metal Oxide Semiconductor) transistors. EPROM is a type of ROM on which data is written or deleted optically. For erasing the content in EPROM, a rock crystal window is provided at top of its packaging.

What is EEPROM?

EEPROM stands for Electrically Erasable Programmable Read Only Memory. It is a type of ROM that uses electrical signals for erasing the data stored in the EEPROM. Basically, EEPROM is an extended variant of EPROM.

The whole circuitry of the EEPROM is encased in an opaque plastic case. The chief advantage of EEPROM is that it does not need to be separated from the circuit for erasing its content. Although, EEPROM is very expensive relative to PROM.

Difference between EPROM and EEPROM

The following highlights all the important differences between EPROM and EEPROM −

EPROM EEPROM
EPROM stands for Erasable and Programmable Read Only Memory. EEPROM stands for Electrically Erasable and Programmable Read Only Memory.
UV (ultra violet) rays are used to erase the content in EPROM. An electric signal is used to erase the contents of EEPROM.
It includes a rock crystal window at the top. The area in an EEPROM is completely sheathed in an opaque plastic case.
The relative cell size in an EPROM is 1. The relative cell size in an EEPROM is 3.
EPROM is considered as the modern version of PROM. EEPROM is considered as the modern version of EPROM.
EPROM is an external programming technique. EEPROM is an external programming technique.
Once erased, EPROM memory can't be reprogrammed. EEPROM can be reprogrammed after erasing (like EPROM).
The transistor used with EPROM consumes 12.5 volts. The transistor used with EEPROM consumes 5 volts.
The hot electron injection programming technique is used with EPROM. The tunnel effect is used as programming technique in EEPROM.
The operation of erasing consumes 15 to 20 minutes in EPROM. Erasing contents of EEPROM consumes 5 milliseconds.
To erase and reprogram the system's BIOS, EPROM chip has to be switched off from the circuit. The operation of erasing and reprogramming can be done without switching off the electrical circuit of the system.

Conclusion

Both EPROM and EEPROM were developed to rectify the problems associated with ROM and PROM. The major advantage of the EPROM and EEPROM over the ROM and PROM is that they can be erased and reprogrammed. The most significant difference between EPROM and EEPROM is that an EPROM is erased by using UV rays, while an EEPROM is erased by using electrical signals.

Updated on: 24-Nov-2022

6K+ Views

Kickstart Your Career

Get certified by completing the course

Get Started
Advertisements