subject: How SD cards progressed [print this page] How SD cards progressed How SD cards progressed
The forbear of the micro and mini SD cards was, of course, the SD card. The SD or Secure Digital card first saw light of day back in August 1999 and has come a long way already.
Three companies with stakes in digital technology decided to develop and market the SD card to compete with another well known company's memory stick design. This latest memory card had a lot in common with its predecessor the MMC or Multimedia Card. However, there were design differences, which were a definite improvement on the older memory card. One such improvement was that it was made to be asymmetrical which meant that, unlike a MMC, it could not be accidentally inserted into a device upside down. SD cards were also designed with the electrical contacts hidden beneath the card's surface. This improvement meant that the contacts could not be accidentally touched by the user's fingers while inserting or extracting the card from the device.
The SD card was slightly thicker than the MMC but the micro SD card and mini SD cards, as their name would suggest, are a lot smaller and thinner than the standard SD card. The 'high capacity' standard meant that the card's capacity for storage was increased to 32 GB. In the future, there may well be an upgrade of this particular specification to allow for greater capacities. The theory is that a SDHC card can store as much as 2048 GB.
SD and SDHC cards have certain compatibility problems. For example, if a device such as a camcorder, a phone or a PDA which do not support the SDHC format specifically will not accept SDHC cards, because although the SDHC card may physically fit the device in question, the device will not recognise the card's memory format. Another issue is that, at the time SDHC cards were introduced onto the market, some non-standard high-capacity cards were already available. Since the two different sorts of high capacity cards were not interchangeable, a certain amount of confusion among consumers was the result.
It cannot be denied that where digital cameras are concerned, Secure Digital cards are certainly an amazing success story. By now, all the leading manufacturers are using SD as part of their cameras' storage Where some smaller electronic devices are being used, the tendency is for micro or mini SD cards to be used. It is possible for mini-SD cards to be used in a standard Secure Digital card slot. All this requires is the use of a passive adapter. The reason this simple adaptation works is that, although the cards may differ in size as well as shape, their electrical interfaces are the same. There are some SD cards with the capability to be used with computers, both desktop and laptop. This is achieved by the use of a USB connector.
At Memory Card Zoo, you will be able to find SD cards and micro SD cards to suit your particular needs; from phones to PDAs, netbooks to desktops, we will have the storage media you require.
