# One Time Programmable
**Wikidata**: [Q9300811](https://www.wikidata.org/wiki/Q9300811)  
**Source**: https://4ort.xyz/entity/one-time-programmable

## Summary
One Time Programmable (OTP) is a form of digital memory that can be written once. This memory type achieves its single-write capability by physically altering its structure, specifically by blowing fuses or antifuses to permanently set the bits. Once programmed, the data stored in OTP memory cannot be changed or erased.

## Key Facts
- One Time Programmable (OTP) is a form of digital memory.
- It is a subclass of programmable read-only memory.
- Data is written once by blowing fuses or antifuses to set bits.
- It is also known by the alias OTP.
- Wikipedia articles related to OTP are available in German (de) and Portuguese (pt) languages.
- It has a sitelink count of 2.
- Its Google Knowledge Graph ID is /g/122vl5c1.

## FAQs
### Q: What is One Time Programmable memory?
A: One Time Programmable (OTP) memory is a type of digital memory that can be written only once. Its unique characteristic is that once data is written, it becomes permanently stored and cannot be altered or erased.

### Q: How does One Time Programmable memory work?
A: Data is written to One Time Programmable memory by a physical process that permanently alters the memory cells. This typically involves blowing microscopic fuses or creating antifuse connections to set the desired bit values, making the stored information irreversible.

### Q: What class of memory does One Time Programmable belong to?
A: One Time Programmable memory is classified as a subclass of programmable read-only memory (PROM). PROM itself is a broader category of digital memory designed to be written once.

## Why It Matters
One Time Programmable (OTP) memory holds significant importance due to its irreversible programming characteristic. By allowing data to be written only once through the physical alteration of fuses or antifuses, OTP provides a highly reliable and non-volatile storage solution for critical, unchangeable information. This permanence ensures that once data is set, it cannot be accidentally or maliciously modified, offering a robust foundation for fixed configurations. It is crucial in applications where data integrity and immutability are paramount, such as storing unique device IDs, calibration parameters, or initial boot code that must remain constant throughout a product's lifecycle. The "write once" nature of OTP memory makes it an essential component for ensuring the long-term stability and security of embedded systems and electronic devices.

## Notable For
- Its unique "write once" characteristic, ensuring data immutability after programming.
- The physical mechanism of programming, which involves blowing fuses or antifuses to set bits permanently.
- Being a specific and irreversible form of programmable read-only memory.

## Body

### Definition and Functionality
One Time Programmable (OTP) refers to a specific type of digital memory. Its fundamental characteristic is that it can be written to only a single time. The process of writing data to OTP memory involves a physical alteration of the memory cells. This alteration is typically achieved by blowing microscopic fuses or creating antifuse connections, which permanently sets the state of individual bits. Once these bits are set, the data stored in the OTP memory becomes fixed and cannot be changed or erased.

### Classification
OTP memory is formally classified as a subclass of programmable read-only memory (PROM). Programmable read-only memory itself is a broader category of digital memory that shares the characteristic of being writable only once.

### Identification and Aliases
One Time Programmable memory is commonly recognized and referred to by its acronym, OTP. Its unique identifier within the Google Knowledge Graph is /g/122vl5c1.

### Global Presence
Information and resources related to One Time Programmable memory are available across various platforms. Specifically, Wikipedia articles discussing OTP are present in multiple languages, including German (de) and Portuguese (pt). The entity has a reported sitelink count of 2, indicating its presence and linkage across different knowledge bases.