5 Types of Read Only Memory(ROM)

As you power up your computer or electronic device, have you ever wondered where all the important information necessary for the system to operate comes from? The answer lies in a type of memory known as Read-only memory or ROM.

Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. It stores important information that is used to operate the system, like firmware. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Therefore, ROM is useful for storing software that is rarely changed during the life of the system, also known as firmware. The manufacturer fits a specifically designed ROM chip into a device during the building process. ROM chip contains integrated circuits. ROM is responsible for holding the vital information necessary for a system to operate, which includes both the hardware and software components.

There are several types of ROM, each with its specific characteristics and applications. Here are some commonly used types of ROM:

Mask ROM (MROM): This type of ROM is created during the manufacturing process, and its contents cannot be changed after production.

Programmable Read-Only Memory (PROM): PROMs can be programmed once using a special programmer. After programming, the content becomes permanent, much like Mask ROM. The difference between PROM and the ROM is that PROM is manufactured as a blank memory, while the ROM is programmed during the manufacturing process.

Erasable Programmable Read-Only Memory (EPROM): EPROMs can be erased using ultraviolet light and reprogrammed multiple times. However, the process of erasing the chip can be time-consuming and complicated.

Electrically Erasable Programmable Read-Only Memory (EEPROM): EEPROMs can be erased and reprogrammed while they are still in the electronic device. This makes them more convenient than EPROMs. It can be erased and reprogrammed about 10,000 times. Both erasing and programming take about 4 to 10 milliseconds.

Flash Memory: Flash memory is a type of EEPROM that can be programmed and erased in blocks at a time. It is commonly used in USB drives, memory cards, and solid-state drives.