EPROM is abbreviated as Erasable Programmable Read-Only Memory. EPROM is a type of power chip that keeps its data despite having no power supply. They can easily store and erase the data and then recover it using Ultraviolet rays. The UV light helps to clear the data on the chip so that it can be later reprogrammed easily. But to write and erase data on an EPROM, you would need a particular type of device PROM programmer. The process of programming in EPROM is mainly referred to as BURNING, and the box into which it is plugged is known as an EPROM burner.
EPROM is a non-volatile memory and was developed by Dov Frohman in 1971 at intel. When an EPROM is programmed, it can retain its data for a minimum of 10 to 20 years. A clear quartz crystal window at the top of the EPROM permits the UV light to erase the data. But you always need to be careful because an excessive amount of data erasing can damage the silicon dioxide layer, and the use of a chip becomes unreliable. Once programmed, it cannot be electrically reversed.
Applications of EPROM
An EPROM was developed to replace ROM and PROM and overcome their disadvantages. Nowadays, EPROM chips are not commonly used in computers, and EPROM memory chips have replaced them. For the mass volume of product parts, mask-programmed ROMs are the minimum cost products to use. However, many weeks of lead time are required to manufacture them. It takes a long time because the artwork for an IC mask layer must be altered so that data can be stored on the ROMs. In earlier days, it was always thought that EPROM would be highly expensive to produce and that it would be restricted to development only. It was soon discovered that small mass production was less costly with EPROM parts, specifically when the benefit of quick upgrades of firmware was considered.
Before the times of EEPROMs and flash memory, some microcontrollers used an on-chip EPROM to store their program data. These microcontrollers may consist of the versions of the intel 8048, the Freescale 68HC11, and the "C" versions of the PIC microcontroller. Like EPROM chips, such microcontrollers came in expensive versions mainly for program development and debugging. The same chip could be available in opaque OTP packaging for production, which was cheaper than the former type. When you leave the dye of such a chip exposed to light, it can change the behavior in surprising ways when it is being shifted from a windowed part for development to a non-windowed part used for production. The windowed version is the expensive one, while the non-windowed version is the less expensive option.
Advantages of EPROM
- EPROM is cost-effective because of which it can be used in mass production.
- It can effectively be used for programming.
- An EPROM is highly convenient for debugging and testing.
- In EPROM, no external memory is needed.
- An EPROM can retain its data even without the supply of power.
Differences Between EPROM and EEPROM
- First of all, EPROM stands for Erasable Programmable Read-Only Memory, and EEPROM stands for Electrically Erasable Programmable Read-Only Memory.
- In EPROM, the data is erased by using UV light, while in EEPROM, it is erased electrically.
- You need to remove the EPROM chip from the computer to erase the data and reprogram it, while for EEPROM, there is no such need.