Browse Definitions:
Definition

phase-change memory (PCM)

Phase-change memory (PCM) is a form of computer RAM (random-access memory) that stores data by altering the state of the matter from which the device is fabricated. The structure of the material can change rapidly back and forth between amorphous and crystalline on a microscopic scale. In the amorphous or disordered phase, the material has high electrical resistance ; in the crystalline or ordered phase, its resistance is reduced. This allows electrical current s to be switched on and off, representing digital high and low states. Working prototype s of PCM chips have been tested by IBM, Infineon, Samsung, Macronix and others.

According to its proponents, PCM technology has the potential to provide inexpensive, high-speed, high-density, high-volume nonvolatile storage on an unprecedented scale. The physical structure is three-dimensional, maximizing the number of transistor s that can exist in a chip of fixed size. PCM is sometimes called "perfect RAM" (PRAM) because data can be overwritten without having to erase it first. This makes it possible for PCM to function many times faster than conventional flash memory while using less power. In addition, PCM chips are expected to last several times as long as currently available flash memory chips and may prove cheaper to mass-produce.

The acronym PCM also stands for pulse code modulation . The acronym PRAM also stands for parameter RAM .

This was last updated in March 2011

Continue Reading About phase-change memory (PCM)

Start the conversation

Send me notifications when other members comment.

By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Please create a username to comment.

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

SearchSecurity

  • copyright

    Copyright is a legal term describing ownership of control of the rights to the use and distribution of certain works of creative ...

  • keylogger (keystroke logger or system monitor)

    A keylogger, sometimes called a keystroke logger or system monitor, is a type of surveillance technology used to monitor and ...

  • password

    A password is an unspaced sequence of characters used to determine that a computer user requesting access to a computer system is...

SearchHealthIT

SearchDisasterRecovery

  • call tree

    A call tree -- sometimes referred to as a phone tree -- is a telecommunications chain for notifying specific individuals of an ...

  • mass notification system (MNS)

    A mass notification system is a platform that sends one-way messages to inform employees and the public of an emergency.

  • disaster recovery as a service (DRaaS)

    One approach to a strong disaster recovery plan is DRaaS, where companies offload data replication and restoration ...

SearchStorage

  • RAID (redundant array of independent disks)

    RAID (redundant array of independent disks) is a way of storing the same data in different places on multiple hard disks to ...

  • data migration

    Data migration is the process of transferring data between data storage systems, data formats or computer systems.

  • compact disc (CD)

    A compact disc is a portable storage medium that can be used for recording, storing and playing back audio, video and other data ...

SearchSolidStateStorage

  • NVMe (non-volatile memory express)

    NVMe (non-volatile memory express) is a host controller interface and storage protocol to enable a solid-state drive to use the ...

  • SSD RAID (solid-state drive RAID)

    SSD RAID (solid-state drive RAID) is a methodology commonly used to protect data by distributing redundant data blocks across ...

  • Tier 0

    Tier 0 (tier zero) is a level of data storage that is faster, and perhaps more expensive, than any other level in the storage ...

SearchCloudStorage

  • RESTful API

    A RESTful application program interface breaks down a transaction to create a series of small modules, each of which addresses an...

  • cloud storage infrastructure

    Cloud storage infrastructure is the hardware and software framework that supports the computing requirements of a private or ...

  • Zadara VPSA and ZIOS

    Zadara Storage provides block, file or object storage with varying levels of compute and capacity through its ZIOS and VPSA ...

Close