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Difference between PROM and EPROM

  • Last Updated : 12 Jun, 2019

PROM stands for Programmable Read Only Memory is the type of ROM is written only. It was meant to fulfil the requirement of a group of ROMs which may contain a selected memory content. It’s memory is written just the once and programmed electrically by the user at the time or when the initial chip fabrication. the required content file is equipped by the user and inserted within the machine referred to as storage coder. There exist a fuse at every programmable association and it’s blown once the association isn’t required.

EPROM stands for Erasable Programmable Read Only Memory is also the type of ROM is read and written optically. To write associate EPROM, its storage cells should stay within the same initial state. EPROM provides reduced storage permanency as compared to PROM as a result of the EPROM is receptive to radiation and electrical noise. in the construction of EPROM, MOS transistors are used.

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The main distinction between PROM and EPROM is that, PROM may be programmed just the once implies that it may be written only 1 time whereas EPROM is erasable; therefore it may be reprogrammed.

Let’s see that the difference between PROM and EPROM:

1.PROM is not reusable.While EPROM is reusable multiple times.
2.PROM is inexpensive.While it is costlier than PROM.
3.The processes of PROMS is irreversible, means it’s memory is permanent.Whereas EPROM’s processes can be reversed.
4.The storage endurance of PROM is high.While EPROM’s storage endurance of PROM is less than PROM.
5.PROM is totally sheathed during a plastic cowl.While EPROM is boxed in during a rock crystal window so the ultraviolet radiation rays will transfer through it.
6.PROM is the type of ROM is written only.While EPROM is also the type of ROM is read and written optically.
7.If there’s miscalculation or error or bug while writing on PROM, it becomes unusable.Whereas if there’s miscalculation or error or bug while writing on EPROM, it will still be used once more.
8.PROM is the older version of EPROM.While EPROM is modern version of PROM.
9.PROM is better than EPROM in terms of flexibility and scale.While EPROM have less flexibility and scalability.
10.In PROM, bipolar transistor is used.While in EPROM, MOS transistor is used.

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