Memory Stick is a removable flash memory card format, launched by Sony in October 1998 , and is also used in general to describe the whole family of Memory Sticks. In addition to the original Memory Stick, this family includes the Memory Stick PRO, a revision that allows greater maximum storage capacity and faster file transfer speeds; Memory Stick Duo, a small-form-factor version of the Memory Stick (including the PRO Duo); and the even smaller Memory Stick Micro (M2). In December 2006 Sony added the Memory Stick PRO-HG, a high speed variant of the PRO, to be used for high definition still and video cameras.
The original memory stick was available in sizes up to 128 MB
, and a sub-version, Memory Stick Select
allowed two banks of 128 MB selectable by a slider switch, essentially two cards squeezed into one. The largest capacity Memory Stick currently available is 16 GB
which was unveiled at the 2008 Consumer Electronics Show
in Las Vegas
. According to Sony, the Memory Stick PRO has a maximum potential size of 32 GB (Available 2009).
The Memory Stick has outlived most other flash memory formats, with a longevity comparable to CompactFlash and SD cards.
Typically, Memory Sticks are used as storage media for a portable device, in a form that can easily be removed for access by a personal computer
. For example, Sony digital compact cameras
use Memory Sticks for storing image files. With a Memory Stick-capable reader (typically a small box that connects via USB
or some other serial connection), a user can copy the pictures taken with the Sony digital camera onto his or her computer. Sony uses and has used Memory Sticks in digital cameras, digital music players
, cellular phones
, the PlayStation Portable (PSP)
, and in other devices, and the Sony VAIO
line of personal computers has long included Memory Stick slots. The exception for now is the A100 DSLR
camera which actually has a CompactFlash slot, although the new A700 DSLR
camera is compatible with Compactflash and Memory Stick Pro Duo formats.
A special Memory Stick can be used by Sony's AIBO robot pet, to enable the use of Aiboware—software intended for use on AIBOs. The Sticks include a copy protection mechanism used by the robot, allowing users to write programs. These are referred to as programmable or programming Memory Sticks and are coloured pink. Only 8 MB and 16 MB versions are available.
The Duo and PRO Duo versions of Memory Stick are used with the Sony PlayStation Portable (PSP), which when inserted into the Memory Stick Slot show saved game data, music, pictures, videos and games.
Formats and form factors
Memory Sticks include a wide range of actual formats, including three different form factors.
The original Memory Stick is approximately the size and thickness of a stick of chewing gum. It was available in sizes from 4MB to 128MB. The original Memory Stick is no longer manufactured.
Memory Stick Select
In response to the storage limitations of the original Memory Stick, Sony introduced the Memory Stick Select
. The Memory Stick Select was two separate 128 MB partitions which the user could switch between using a (physical) switch on the card. This solution was fairly unpopular, but it did give users of older Memory Stick devices more capacity.
Memory Stick PRO
The Memory Stick PRO
, introduced in 2003 as a joint effort between Sony and SanDisk
, would be the longer-lasting solution to the space problem. Most devices that use the original Memory Sticks support both the original and PRO sticks since both formats have identical form factors. Some readers that were not compatible could be upgraded to Memory Stick PRO support via a firmware
update. Memory Stick PROs have a marginally higher transfer speed and a maximum theoretical capacity of 32 GB, although it appears capacities higher than 4GB are only available in Duo and Pro Duo form factors. High Speed Memory Stick PROs are available, and newer devices support this High Speed mode, allowing for faster file transfers. All Memory Stick PROs larger than 1 GB support this High Speed mode, and High Speed Memory Stick Pros are backwards-compatible with devices that don't support the High Speed mode. High capacity memory sticks such as the 4 GB versions are expensive compared to other types of flash memory such as SD cards and CompactFlash.
Memory Stick Duo
The Memory Stick Duo
was developed in response to Sony's need for a smaller flash memory card for pocket-sized digital cameras and cell phones. It is slightly smaller than the competing Secure Digital
(SD) format and roughly two thirds the length of the standard Memory Stick form factor. Memory Stick Duos are available with the same features as the larger standard Memory Stick, available with and without High Speed mode, and with and without MagicGate
A simple adapter allows Memory Stick Duo to be used in devices designed to accept the original Memory Stick form factor.
Memory Stick PRO Duo
The Memory Stick PRO Duo
quickly replaced the Memory Stick Duo due to its size limitation of 128MB and slow transfer speed. Memory Stick PRO Duos are available in all the same variants as the larger Memory Stick PRO, with and without High Speed mode, and with and without MagicGate support. In March 2008, Sony released a 16GB version of the Memory Stick PRO Duo. Sony has plans to release a 32GB version in 2009. Theory says though that the theoretical maximum could be 2TB, equal to the SDHC limit.
Memory Stick PRO-HG Duo
On December 11 2006
, Sony, together with SanDisk, announced the Memory Stick PRO-HG Duo
. While only serial and 4-bit parallel interfaces are supported in the Memory Stick PRO format, an 8-bit parallel interface was added to the Memory Stick PRO-HG format. Also, the maximum interface clock frequency was increased from 40 MHz to 60 MHz. With these enhancements, a theoretical transfer rate of 480Mbit/s (60Mbyte/s) is achieved, which is three times faster than the Memory Stick PRO format.
Memory Stick Micro
In a joint venture with SanDisk, Sony released a new Memory Stick format on February 6, 2006. The Memory Stick Micro (M2) measures 15 × 12.5 × 1.2 mm—roughly one-quarter the size of the Duo, around the size of a fingernail—with 128MB, 256 MB, 512 MB, 1 GB, 2 GB, 4 GB, 8GB, 16GB capacities, with a theoretical limit of 32 GB. SanDisk has recently launched a 16GB M2 memory stick. Maximum transfer speed is 160 Mbit/s. It comes with an adapter, much like the Duo Sticks, to ensure physical compatibility with current PRO devices. However, not all devices with a PRO slot are compatible with the M2/Adapter combination, as the larger capacities can pose problems for the software of older devices. One example are some Sony Clie PDAs USA version, which can not use M2 cards larger than 2 GB.
However it also has the deficit of being unable to function when introduced to some computers.
Mark 2 Certification
As of early 2008, Mark 2
-certified versions of Memory Stick PRO Duo became available (Faster than the standard Memory Stick PRO Duo released before). The Mark 2 designation indicates the Memory Stick is suitable for use with AVCHD
recording products or other faster Memory Stick enable devices by providing appropriate minimum write performance.