Browse Definitions :
Definition

SRAM (static random access memory)

What is SRAM (static random access memory)?

SRAM (static RAM) is a type of random access memory (RAM) that retains data bits in its memory as long as power is being supplied. Unlike dynamic RAM (DRAM), which must be continuously refreshed, SRAM does not have this requirement, resulting in better performance and lower power usage. However, SRAM is also more expensive than DRAM, and it requires a lot more space.

SRAM is commonly used for a computer's cache memory, such as a processor's L2 or L3 cache. It is not used for a computer's main memory because of its cost and size. Most computers use DRAM instead because it supports greater densities at a lower cost per megabyte (MB). However, SRAM is often used for other purposes. For example, it might be part of a RAM digital-to-analog converter (RAMDAC) on a computer's video or graphic card. It might also be used in a disk drive as buffer cache, in a peripheral such as a printer or LCD display, or in a network device such as router or switch.

SRAM can be found in other devices ways as well. For example, SRAM chips are often used in cell phones, wearables and other consumer electronics. They might also be embedded in medical products, which can include anything from hearing aids to body area networks that include multiple devices embedded in the body. In addition, SRAM is used in toys, appliances, automobiles, industrial equipment and a wide range of IoT devices.

comparing memory types

Static RAM vs. dynamic RAM

Both SRAM and DRAM are types of volatile memory, which means they lose their data if the power goes out. Despite this similarity, they differ in important ways. Much of this difference lies in how they're constructed. SRAM uses a flip-flop circuit to store each data bit. The circuit delivers two stable states, which are read as 1 or 0. To support these states, the circuit requires six transistors, four to store the bit and two to control access to the cell. Because of all these transistors, a SRAM chip has a much lower capacity that a DRAM chip of comparable size.

DRAM requires only one transistor and one capacitor to store a bit. The capacitor holds the electrons that determine whether the bit is a 0 or 1. The transistor acts as a switch for reading and changing the capacitor's state. Unfortunately, DRAM capacitors have a tendency to leak electrons and lose their charge, so they must be refreshed periodically to retain their data, which can affect access speeds and increase power usage.

Because of the different architectures, SRAM tends to perform better and require less power, especially when it sits idle. However, it cannot store as much data as DRAM, and it is more expensive. The following table outlines several of the key differences between SRAM and DRAM.

SRAM vs. DRAM
The differences between static random access memory (SRAM) and dynamic random access memory (DRAM).

Both SRAM and DRAM easily outperform most of today's nonvolatile memory, even the latest generation of flash drives and storage class memory devices such as Intel Optane. Computer systems are likely to rely on SRAM and DRAM for some time to come, although there is a great deal of research underway looking into alternatives to both memory and storage.

Until then, SRAM and DRAM offer both advantages and disadvantages that make them best suited for specific use cases. This is why DRAM is used for a computer's memory and SRAM is used for its cache, which requires the fastest possible access speeds. In fact, SRAM could potentially benefit any type of device in which performance and power usage are of primary concern.

See also: Cache vs. RAM: Differences between the two memory types and Flash memory vs. RAM: What's the difference?

This was last updated in May 2022

Continue Reading About SRAM (static random access memory)

Networking
  • firewall as a service (FWaaS)

    Firewall as a service (FWaaS), also known as a cloud firewall, is a service that provides cloud-based network traffic analysis ...

  • private 5G

    Private 5G is a wireless network technology that delivers 5G cellular connectivity for private network use cases.

  • NFVi (network functions virtualization infrastructure)

    NFVi (network functions virtualization infrastructure) encompasses all of the networking hardware and software needed to support ...

Security
  • virus (computer virus)

    A computer virus is a type of malware that attaches itself to a program or file. A virus can replicate and spread across an ...

  • Certified Information Security Manager (CISM)

    Certified Information Security Manager (CISM) is an advanced certification that indicates that an individual possesses the ...

  • cryptography

    Cryptography is a method of protecting information and communications using codes, so that only those for whom the information is...

CIO
  • B2B (business to business)

    B2B (business-to-business) is a type of commerce involving the exchange of products, services or information between businesses, ...

  • return on investment (ROI)

    Return on investment (ROI) is a crucial financial metric investors and businesses use to evaluate an investment's efficiency or ...

  • big data as a service (BDaaS)

    Big data as a service (BDaS) is the delivery of data platforms and tools by a cloud provider to help organizations process, ...

HRSoftware
  • talent acquisition

    Talent acquisition is the strategic process an organization uses to identify, recruit and hire the people it needs to achieve its...

  • human capital management (HCM)

    Human capital management (HCM) is a comprehensive set of practices and tools used for recruiting, managing and developing ...

  • Betterworks

    Betterworks is performance management software that helps workforces and organizations to improve manager effectiveness and ...

Customer Experience
  • martech (marketing technology)

    Martech (marketing technology) refers to the integration of software tools, platforms, and applications designed to streamline ...

  • transactional marketing

    Transactional marketing is a business strategy that focuses on single, point-of-sale transactions.

  • customer profiling

    Customer profiling is the detailed and systematic process of constructing a clear portrait of a company's ideal customer by ...

Close