Definition: EPROM (pronounced ee-prom ) stands for Erasable Programmable Read-Only Memory. EPROM is a type of ROM chip that can retain the data even if there is no power supply. The data can be erased and reprogrammed by using ultraviolet (UV) light. The UV light clears the data on the chip so that it can reprogram. For writing and erasing data on the EPROM, we need a particular device which is known as PROM programmer. The process of programming an EPROM is often called BURNING, and the box into which it is plugged to program it an EPROM burner.
EPROM is a non-volatile memory. EPROM is developed by Dov Frohman in 1971 at Intel. A programmed EPROM can retain its data for a minimum of 10 to 20 years. There is a transparent quartz crystal window at the top of the EPROM which allows the UV light to erase the data.
The data on EPROM can be erased a limited number of times because excessive erasing damages the silicon dioxide layer and it makes the use of chip unreliable. The programming process on EPROM is not electrically reversible.
EPROM was the replacement for ROM (Read-Only Memory) and PROM (Programmable Read-Only Memory), and it was developed to overcome the disadvantages of ROM and PROM.
Nowadays EPROM chips are not used in the computer, and these EPROM chips replaced by EEPROM memory chips.
We’ll be covering the following topics in this tutorial:
Difference between EPROM and EEPROM
| EPROM | EEPROM |
| • EPROM stands for Erasable Programmable Read-Only Memory. | • EEPROM stands for Electrically Erasable Programmable Read-Only memory. |
| • In EPROM, ultraviolet (UV) light is used to erase the content. | • In EEPROM, the data is erased using an electrical signal. |
| • We have to remove the EPROM chip from the computer for erasing and reprogramming of the data. | • There is no requirement of removing the chip from the computer for erasing and reprogramming of the data. |
| • An EPROM has a transparent quartz crystal window at the top. | • EEPROM completely encased in an opaque plastic case. |
| • EPROM is an older technology. | • An EEPROM is modern technology. |
Advantages of EPROM
• It is cost-effective.
• It can reprogram.
• An EPROM is convenient for testing and debugging.
• Here, no external memory is required.
• An EPROM memory can retain the data even without the power.
Disadvantages of EPROM
• An EPROM makes use of a transistor which has higher resistance.
• It has high static power consumption.
• An EPROM makes use of ultraviolet light for erasing the data, unlike EEPROM.
• In EPROM, you cannot erase the data byte per byte like EEPROM.
• For erasing and reprogramming of the data, you have to remove the EPROM chip from the computer.
• An EPROM takes some time to erase the data.
• The programming of EPROM is slow as compared to the other forms of memory.
• EPROM is costly as compared to PROMs.
Applications of EPROM
• An EPROM memory chip is to store computer BIOS which used a bootstrap loader.
• Some micro-controllers make use of an EPROM memory chip for the storage of the data.
• An EPROM can also found in the making of the video game.
• EPROM mostly used on our personal computers.
Dinesh Thakur holds an B.C.A, MCDBA, MCSD certifications. Dinesh authors the hugely popular