Programmable read-only memory

Definition

Programmable read-only memory (PROM) is a type of non-volatile memory that can be programmed once after manufacturing, allowing data to be written to it using a special programming device. This technology bridges the gap between traditional read-only memory (ROM) and more flexible forms of memory, enabling specific applications to store permanent data. PROM is especially useful in applications where the data does not need to be altered frequently, offering a reliable solution for embedded systems and electronic devices.

5 Must Know Facts For Your Next Test

1. PROM is created by fusing links inside the chip, which makes it irreversible after programming, leading to its classification as non-volatile memory.
2. The primary advantage of PROM is its ability to hold data permanently without the need for power, making it suitable for applications like firmware storage.
3. While PROM can only be programmed once, it is often used in situations where the final application does not require changes to the stored data.
4. The programming process for PROM typically involves applying higher voltage to specific memory cells, which alters their state and records the intended data.
5. Due to its reliability and simplicity, PROM remains relevant in various applications, especially in consumer electronics and specialized industrial equipment.

Review Questions

• How does programmable read-only memory differ from other types of read-only memory like EPROM?
  • Programmable read-only memory (PROM) differs from EPROM primarily in its ability to be programmed only once after manufacturing, while EPROM can be erased and reprogrammed multiple times using ultraviolet light. This characteristic makes PROM suitable for applications where permanent data storage is needed without future modifications. In contrast, EPROM provides flexibility for updates or changes but requires more complex programming processes and additional equipment.
• Discuss the advantages and disadvantages of using PROM in embedded systems compared to Flash Memory.
  • Using PROM in embedded systems has the advantage of providing permanent data storage that does not require power, which is critical for firmware and essential operational instructions. However, PROM's inability to be reprogrammed limits its flexibility, making it less suitable for applications that require frequent updates. In comparison, Flash Memory offers the ability to erase and rewrite data multiple times, providing greater adaptability for evolving applications but at the cost of slightly higher complexity in managing data retention and reliability.
• Evaluate the impact of programmable read-only memory on the design of electronic devices in terms of cost-effectiveness and performance.
  • Programmable read-only memory has significantly influenced the design of electronic devices by balancing cost-effectiveness with reliable performance. By allowing manufacturers to program essential data into devices permanently without ongoing maintenance costs or power requirements, PROM reduces overall production expenses while ensuring consistent functionality. As a result, many consumer electronics and industrial products leverage PROM's advantages to achieve efficient designs that meet user needs without overcomplicating storage solutions or incurring unnecessary expenses.

Related terms

EPROM: Erasable programmable read-only memory (EPROM) is a type of memory that can be erased and reprogrammed using UV light, allowing for multiple cycles of programming.

Flash Memory: Flash memory is a type of non-volatile storage that can be electrically erased and reprogrammed, providing a more versatile alternative to PROM.

Mask ROM: Mask ROM is a form of ROM that is programmed during the manufacturing process and cannot be modified afterward, offering a permanent storage solution.