What Is A PROM? What Are Its Characteristics And Uses?

Do you know computing devices rely on ROM for initial operations? If you don’t, I will recommend you to check out my article on ROM. The quickest way is to type ROM in the search bar and you will find the said article.

what is a prom
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Just a short revision, ROM or ROM or Read Only Memory provides a set of guidelines to a number of computing devices including computers.

Despite computers being smart enough to solve unimaginably complex mathematical problems, they simply can’t function without a ROM. When you power on the computer, it remains blank until the ROM provides it with the initial instructions on what to do.

There are many types of ROM used in computing devices. As for the following post, we will just stick to one called PROM. Scroll down and unlock the rocket science behind it.

What Is A PROM?

PROM or Programmable ROM is a memory device installed in laptops and computers. Also called Programmable Read Only Memory, it is non-volatile in nature and can’t be programmed more than once.

This means, If you enter data into a PROM, there is no chance you can erase it afterward. It is a memory device backed with bipolar transistors for operational functioning.

Developed especially for the ICBM program of the United States Air Force in 1956, PROM took a few years to be commercialized. When introduced in the commercial market in the early 1960s, it was the highest standard Read-Only Memory device.

PROM remained an inexpensive and readily available coding solution for computers and many other types of electronic devices for more than a decade.

How Is A PROM Programmed?

Understanding the science behind the programming of a PROM is pretty simple. There is no complex rocket science involved in the programming of a PROM at all. Instead, it is a process that involves a little bit of burning of the fuses.

A PROM device consists of a central chip to hold the data and several fuses for programming. After the PROM device is manufactured, a few of its fuses are burned while others are kept open. While the burned fuses represent zero, the opened fuses represent one.

This process leads to the creation of a binary pattern of zeros and ones that acts as a program for a PROM. Simple enough, right? Now get to know, It is because of the burned fuses that it is impossible to erase the program of a PROM.

Yeah, if you can reverse the process of burning the fuses, you can reprogram the PROM which is simply irrational and out of reality.

Characteristics Of PROM

A PROM owns a number of the following characteristics that make it the most unique type of ROM.

Data Retention

PROMs are famed for their impressive capability to retain data. When it comes to all types of ROM, PROMs can retain the data for the longest period of time. They are specifically designed to retain data for longer periods of time. In fact, according to some manufacturers, PROMs can retain the data for decades. It equates to a data retention capacity of several times more than other types of ROM.

No Data Reading

Unlike other types of ROM, PROMs can’t be read. They can only be utilized for one-time data writing. Once the data is written on a PROM, there is no way to read it.


If used in a computing machine, you can’t use a PROM device again. It is no less than a fun fact that PROMs are built to be used only once. They can’t be recycled to be reused in another computing machine.

No Error Recovery

PROMs are sophisticated memory devices with no room for errors. They require special attention from a programmer during the programming process. If there is an error during the programming process of a PROM, it becomes useless.

Uses Of PROM

While PROMs have been widely applied to computers and laptops, there is more to their uses than just that. Since PROMs are code carriers, they have been used in other types of devices as well.

For example, PROMs have been included in mobile phones for User Specific Selections. They have also been applied to video game consoles and radio-frequency identification (RFID) tags. Other uses of PROMs include automotive, HDMI, and medical devices.

Despite PROMs can be found on a number of devices, they are primarily dedicated to computers and laptops. It wouldn’t be wrong to say the PC industry is the largest beneficiary of PROM devices.

Frequently Asked Questions

Wrap Up

In the domain of memory systems, the invention of the PROM memory device is a separate chapter to be discussed. It is fascinating to realize that several computer components were basically invented for military purposes including PROMs.

It is also amazing to know that after serving in the military, these components or hardware made their way into the commercial market and became widely available to the public. Soon, I will create a separate post about all the computer components or hardware that were first developed for military purposes and were later commercialized.

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Bilal Khan
Bilal Khan

Bilal might look like a Bearded Caucasian right out of a Viking movie but trust me he's a native Pakistani. He has a long list of hobbies among which staying updated on the Latest Technology and Hardware happens to be on the top. If you are looking for detailed hardware explanations through no tricky terminologies, follow him to read Tech Content curated perfectly for the human brain.

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