Difference Between EEPROM and EPROM

Edited by Diffzy | Updated on: April 30, 2023


Difference Between EEPROM and EPROM

Why read @ Diffzy

Our articles are well-researched

We make unbiased comparisons

Our content is free to access

We are a one-stop platform for finding differences and comparisons

We compare similar terms in both tabular forms as well as in points


Read-only memory, often known as ROM, is a kind of computer memory that stores only data that cannot be altered in any way. Everyone is familiar with this type of memory. Because it is a non-volatile memory, it cannot be altered very readily, and in certain cases, it cannot even be altered at all. However, current ROMs have the capability of being deleted and reprogrammed in some kind.

There are two forms of programmable read-only memory: EEPROM and EPROM (ROM). Both of these things are examples of nonvolatile memory, which is a kind of storage used in computers to store programs. Both of them are considered to be external programming devices. They can have their memories wiped clean and rewritten. EEPROM is an expanded form of EPROM, which is an extended version of PROM. Likewise, PROM was an extended version of EPROM.

There is a distinction to be made between these two forms of ROM, also known as Random Access Memory, however, EPROM and EEPROM are both ROMs. But before we get into that, it would be helpful if you could tell us a little bit more about ROM. It is a sort of non-volatile memory that we either have no control over at all or very little control over at all. On the other hand, it is not out of the question for us to delete the current ROM and then rewrite it.


The most significant distinction between EEPROM and EPROM is that the data stored in EEPROM may be overwritten using electric impulses, while the data stored in EPROM can be overwritten using ultraviolet rays. The more up-to-date successor of EPROM is known as EEPROM. In addition, contemporary EEPROM supports operations that include several bytes per page. In addition, it erases faster than an EPROM.

The EEPROM memory is a non-volatile kind of storage. It is an enhanced form of EPROM that gives you the ability to store data as well as read, write and modify that data. Because of this, it is superior to EPROM since it has a greater number of functionalities. EEPROM is often used for activities that involve several bytes per page. Through the application of electric impulses, its contents may be wiped clean in a matter of milliseconds.

An EPROM is essentially a more advanced form of PROM. Memory cannot be lost if the power goes off. In addition to that, it enables you to rewrite data. Even though the process just takes a few minutes, The data may be removed from the medium by subjecting it to UV radiation. Because it emits ultraviolet light, a mercury vapor lamp is a suitable choice for this application.

There are many different altered forms of RAM, and two of them are called EPROM and EEPROM. Both of them can be readily erased and reprogrammed, but the pace at which either of these operations may be performed is exceedingly slow. Erasing anything needs using certain specialized tools and equipment. As a result, we can only do this action a certain amount of times. There is a fundamental distinction that may be made between EPROM and EEPROM. Using UV (ultraviolet) radiation, it is possible to delete the information stored in an EPROM. On the other hand, to delete information from an EEPROM, electric impulses are required to be used.

Difference Between EEPROM And EPROM in Tabular Form

Parameters of Comparison EEPROM EPROM
Definition A more advanced kind of EPROM that can store data. In addition to that, it enables the rewriting of programming. A kind of ROM that permits the writing of new data.
Programming Technique The programming method known as the tunnel effect is used here. The method of programming that is used is called "hot electron injection."
Erasing Technique The information stored on it is wiped clean using electric impulses. Erasing data using ultraviolet radiation is a common practice.
Time Takes to Erase It happens in a matter of milliseconds. It takes around 15 to 20 minutes to complete.
The relative size of the cell The size of the cell of others is three. The size of the cell in comparison to other cells is one.

What is EEPROM?

EEPROM is an acronym that stands for electrically erasable programmable read-only memory. EEPROM is often referred to as E2PROM. It is a nonvolatile memory type that is used in computing devices such as PCs. The information that has been saved in this kind of form is simple to access when it is needed. For data to be stored, it is also used in integrated microcontrollers for electrical devices.

The majority of the time, it is used in the manufacturing of security devices such as smart cards, remote keyless entry systems, Sim cards, Credit cards, etc. It enables the storing of data in volumes that are not very large. Additionally, it enables the erasure and subsequent reprogramming of individual bytes. It doesn't take more than a few seconds to delete the info. In an EEPROM, the data may be deleted by the use of electric impulses.

To delete a byte from an EEPROM memory, a structure consisting of two transistors is necessary for each bit. It just requires 5 volts of power since the transistor that is used in it has a low voltage need. The tunnel approach is used to program EEPROMs and is one of their programming methods.

Products like digital potentiometers, digital temperature sensors, and real-time clocks, amongst others, all make use of EEPROM, although in very small quantities. However, this technology does have certain restrictions attached to it as well. The only two restrictions are the capacity to store data and the duration of the test. The greatest number that may be reached for endurance is one million. And the maximum amount of time that data may be stored in ten years.

It is not necessary to remove the EEPROM from the computer to delete the information stored on it, which is one of the numerous benefits of using this kind of memory.

Electrically Erasable Programmable ROM is what is meant to be referred to when using the word EPROM. When clearing the data stored in an EEPROM, this kind of ROM makes use of electrical current. The memory in an EEPROM may be non-volatile. The basic input/output system (BIOS) of a computer or laptop may take advantage of its limited capacity to store data and information. It may take the place of both PROM and EPROM in a computer's memory.

To delete data from an EEPROM, which stands for "Electrically Erasable Programmable Read-Only Memory," an electric signal must be sent through the device. An EEPROM may be a non-volatile memory, which means that it can keep its data even if the power supply is turned off. It holds the relatively little amount of data required for the BIOS of a laptop or personal computer. It was a replacement in every sense of the word for both the PROM and the EPROM.

What is  EPROM?

Erasable Programmable Read-Only Memory is what is meant by the acronym EPROM. An external programming integrated chip, sometimes known as an expanded PROM, is what you'll find here. There is an optical reading and writing capability built into this kind of ROM. The EPROM is a kind of chip that remembers data and can recover it when needed. Even if the power supply fails, the data on this chip will not be lost. Your data will remain secure in this manner.

The EPROM features a rock-solid window made of clear rock crystal at the very top, through which one can see the silicon chip. To delete data from an EPROM, the memory device must be removed from the computer. It is necessary to disconnect it from the computer circuit before exposing it to the UV light source, such as a mercury-vapor lamp, which will cause the memory to be removed. The amount of time needed might vary depending on the source of the UV radiation. It takes many weeks for sunshine to eradicate the memory.

After then, reprogramming the computer is an available option. In addition, the process of programming EPROM cannot be electronically reversed after it has been completed. Data stored on a programmed EPROM chip may remain accessible for at least ten to twenty years.

When it comes to programming the EPROM, a technique known as hot electron injection programming is used. The MOS transistor in an EPROM may operate at voltages of up to 12.5 volts. The transistors need to be subjected to a greater voltage for the data to be stored in the memory.

Erasable Programmable ROM is what the name EPROM refers to when broken down into its acronym form. It is a special kind of ROOM that can be written in and read using optical signals. The storage cells that it includes must continue to be in the beginning phases for a linked EPROM to be written. In comparison to PROM, EPROM has a much lower storage permanence. As a direct consequence of this, the EPROM will now be susceptible to undesired radiation and electrical noise. MOS transistors are essential to the manufacturing process of EPROM and must be used.

Another kind of ROM that can be read and written optically is called EPROM, which stands for erasable programmable read-only memory. The storage cells of an EPROM must remain in the same starting condition to write data to it. EPROM has a lower storage permanence compared to PROM as a consequence of EPROM being responsive to radiation and electrical noise. This is in contrast to PROM, which is not receptive to any of these factors. MOS transistors are used throughout the manufacturing process of EPROMs.

Main Differences Between EEPROM And EPROM in Points

  • The data stored in an EPROM device may be overwritten by an electric signal, but the data stored in an EEPROM device must be overwritten by ultraviolet radiation.
  • EEPROM cells have a relative size of three times that of EPROM cells, which are just one.
  • EEPROM may have its information wiped off in moments, but EPROM takes many minutes.
  • Since EEPROM is an expanded version of EPROM, it possesses more advanced functionality than its predecessor.
  • The transistor that is used in EEPROM only requires 5 volts, but the transistor that is used in EPROM requires 12.5 volts.
  • The memory of an EEPROM does not need to be removed from the computer to be erased, however, an EPROM must be removed for the memory to be erased.
  • When we want to erase the data that is stored in an EPROM, we have to make use of UV rays, but when we want to delete the data that is stored in an EEPROM, we have to make use of electrical signals.
  • In an EEPROM, the memory remains enclosed in a plastic casing that is opaque, in contrast to an EPROM, which has windows made of quartz crystals that are see-through at the very top.


Both EEPROM and EPROM are examples of non-volatile memory, which is a kind of storage that may be found in computers and other electronic devices. The most up-to-date format is known as EEPROM. In an EEPROM, the data may be erased using electric impulses, and the process only takes a few moments. In addition to having a rapid speed, it also has a high density. The majority of the time, it is used when just a limited quantity of storage is available.

EPROM's information must be erased over a much longer period than EEPROM's, and EPROM's transistor requires a higher voltage supply. It deletes its material by the use of UV light-based methods. The silicon chip that is used in EPROM can be seen on top of it. Therefore, removing the chip from the computer is necessary to delete the data stored on it.

ROM and PROM were initially more cost-effective, but the expense of modifying them over time increased, and users were unable to alter the information contained in the BIOS. As a result, EPROM was developed as a substitute for ROM and PROM. As a result, EPROM was designed to address the issues that were caused by ROM and PROM. EEPROM, on the other hand, is the updated version of EPROM.


Cite this article

Use the citation below to add this article to your bibliography:



MLA Style Citation

"Difference Between EEPROM and EPROM." Diffzy.com, 2024. Mon. 17 Jun. 2024. <https://www.diffzy.com/article/difference-between-eeprom-and-eprom-731>.

Edited by

Share this article