Difference Between Cf And Sd Cards

By | 11/10/2022

A CompactFlash menu (CF card) is a memory card format developed by SanDisk in 1994 that uses flash memory technology to store data on a very pocket-size portable device. It has no moving mechanical parts and does non need a bombardment to retain data. Small-scale retention cards allow users to add information to a wide variety of computing devices. CF cards today are primarily used every bit removable retentiveness for college-end digital photo and video cameras.

The original CompactFlash carte du jour was congenital using NOR wink memory. NOR flash has the advantage of being able to execute programs directly from flash without having to be copied in a device’due south system random access memory (RAM). Notwithstanding, NAND is better suited for big amounts of information storage and became the default blazon of flash memory used in all removable retentiveness cards, including the CompactFlash card and its primary competitor, the Secure Digital (SD) bill of fare.

Considering flash is nonvolatile retentivity, stored information is retained when a device’s power source is turned off or lost. A CF card features solid-land construction, which makes information technology much more rugged than most traditional storage devices. The operating daze rating (basically, the height they tin be dropped from and still piece of work) for a CF bill of fare is 2,000 gauss (1000) compared to a 100 G to 200 Yard rating for the mechanical drive of a typical portable computing device. This translates to a drop to the floor from x anxiety versus a single pes for the mechanical deejay drive.

CompactFlash image

CompactFlash is a pop card choice for use with digital single-lens reflux cameras. A high-stop version, Ultra CompactFlash (Ultra CF), is optimized for more demanding photography, such every bit a apace shot succession of loftier-resolution pictures or pictures of a moving subject. Ultra CF provides a transfer charge per unit twice that of SanDisk’s standard memory cards, allowing data to be chop-chop saved and the photographic camera to be ready to capture another image.

CFast, or CompactFast, combines the CompactFlash card form gene with the Series ATA (SATA) interface.

Technical specifications and vendors

Based on the Parallel Avant-garde Technology Zipper (PATA) interface, CF cards measure 42.8 mm by 36.iv mm (well-nigh the size of a matchbook) and are bachelor with storage capacities ranging up to 512 gigabytes (GB).

CompactFlash cards support three.3V and 5V functioning and can switch between the two. This varies from other small-scale form factor flash memory, which tin can only operate at 1V.

There are two types of CF cards, in varying thicknesses, to accommodate unlike capacities: Type I CF cards are 3.3 mm thick vs. five.0 mm for Blazon Ii cards. The extra thickness of a Type 2 CompactFlash carte is because almost all of them were Microdrives, a tiny spinning hd format originally developed by IBM.

SanDisk is nonetheless one of the largest suppliers of CF cards in the world, simply it has enough of competition. Consistently getting loftier reviews from digital imaging websites are cards from Kingston Technology, Lexar and Transcend Data. Other suppliers include Delkin Devices, KomputerBay and Verbatim Americas.

While 512 GB CompactFlash cards are bachelor, the best-selling size on Amazon is 32 GB, possibly because of the higher cost of CF cards compared to SD cards.

CompactFlash Association and compliance

A CompactFlash bill of fare is self-tested for interoperability by member manufacturers of the CompactFlash Association (CFA), which was established in 1995. The group cites 80 members and states it is primarily focused on the needs of the professional photo and video markets, as well every bit the industrial marketplace.

Cards completing this testing are labeled as follows:

  • CF 4.1a:
    Products are widely available at speeds upwards to 90 megabytes per second (MBps) sequential access speed.
  • CF 5.0:
    Products have more efficient commands and support TRIM operations providing consistent speed.
  • CF 6.0:
    Implements Ultra Direct Mode Access 7 (UDMA seven), which provides bus speeds upward to 167 MBps, and supports the Sanitize command.

In addition to setting standards for CF and CFast cards, the CFA handles standards for the newest removable flash retentivity card format, XQD. Instead of connecting via the PATA bus equally in a CF card or the SATA jitney with a CFast card, XQD cards connect via the much faster PCI Express (PCIe) motorcoach. A XQD card measures 29.6 mm by 38.5 mm, and is iii.viii mm thick.

Boosted wink retentiveness card formats

To save and transfer files, images and songs among devices that are ever decreasing in physical size, newer wink memory card formats were introduced. For example, Secure Digital memory cards — which are regulated past the SD Association, an industry organization similar to the CompactFlash Association — come in a variety of styles and capacity. SD cards are 32 mm by 24 mm by 2.1 mm in size. They are easy to spot due to their cut-corner profile.

SD cards accept replaced the bulkier CompactFlash bill of fare in many device applications because of smaller size, lower weight and lower cost. Depending on the manufacturer and factors such as read/write speed, an SD bill of fare tin be equally much as one-half the cost of a CF card of equivalent data storage size.

MiniSD and microSD memory cards have been designed for apply in mobile phone engineering. MiniSD cards are 21.5 mm by 20 mm by i.4 mm in size, while microSD cards are 15 mm by 11 mm by ane mm in size.

The main difference, bated from size and cost, betwixt SD cards and the CompactFlash card is that SD cards do not contain a microcontroller.

Other types of removable flash-based retentiveness cards that take been developed include Sony’s Retentivity Stick Duo, MultiMediaCard (MMC) and the xD-Picture Card. The Memory Stick is the only one of these formats still used with any regularity, but the MMC has gained a new life as a form of embedded wink memory for many device applications requiring reliability, such every bit in the automotive industry.

XQD cards used the first generation of the PCIe connection, capping out at a speed of 250 MBps. In April 2017, the CFA announced a new protocol, CFexpress 1.0, which is based on PCIe Gen iii and the NVM Express (NVMe) protocols. Information technology tin can operate at data speeds of upwardly to ii GBps and has the same grade cistron equally XQD cards.

This was last updated in
May 2017

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Source: https://www.techtarget.com/searchstorage/definition/CompactFlash-card