Memory cards are generally characterized by small size, large storage capacity, etc.. They are independent storage media for mobile phones, digital cameras, portable computers, MP3, and other digital products. They are generally card forms, so they are collectively referred to as “memory cards.” Also known as “digital memory card”, “digital memory card”, “storage card” and so on. It is often used as a storage vehicle for our daily life. Let’s take stock of the memory cards we use in our lives and their applications.
The memory cards mainly include MMC cards, SD cards, memory sticks, PCIe flash cards, XQD cards, CF cards, XD image cards, SM cards, and M2 cards. They are described below:
The MMC Card
It is mainly aimed at digital images, music, mobile phones, PDAs, e-books, toys and other products. Its size is only 32mm × 24mm × 1.4 mm and its weight is only 1.5 grams. However, due to the lack of support from consumer digital manufacturers, there are not many products that can use MMC memory cards in the digital product market.
SD card(Secure Digital)
Developed by Matsushita, Toshiba, and SanDisk in Japan, it is 32mm × 24mm × 2.1 mm in size and weighs only 2 grams, but it has the characteristics of large capacity, high data transmission rate, and good flexibility. The structure of the SD card guarantees the security of digital file transmission and is easily reformatted, so it has a wide range of applications. Many digital cameras use SD as a storage medium. This also makes the SD card the most widely used memory card.
Mini SD was developed from SD cards. Performance is not much different from traditional SD cards. The Mini SD card, like the SD card, has a hardware data write protection switch to avoid the risk of content being mistakenly deleted. However, the Mini SD card is smaller in size, only 21.5 mm × 20 mm × 1.4 mm, which is 40 % less than the SD card. It can be used with a dedicated switching card and is fully compatible with the standard SD card slot. On the other hand, the most important thing is that the Mini SD card uses a low-power design and is therefore more suitable for mobile communication devices than the SD card. At present, it is mainly used on information terminal devices such as mobile phones, PDAs, and handheld computers.
The TF card, also known as the T-Flash card, full name: TransFLash(aka: Micro SD), is a very small flash memory card developed by Motorola and SANDISK. It has the advantage of being very small, mainly for mobile phones, but with increasing capacity, it slowly began to apply to a wider area. At the same time, it can also be connected to the SD card slot with a adapter and has a large capacity.
The SM Media card is a type of microstorage card, similar to the SD card. Published by Toshiba Corporation in November 1995. SmartMedia uses a 22-pin interface that uses physical formats and logical formats, in which physical formats ensure compatibility between different device models and are mandatory for systems and control vendors. The physical format is based on the FAT standards of ATA and DOS files to make it easier to exchange data between different systems, but the configuration of the physical format will vary in the size of the page, depending on the type of memory and the capacity of the memory card. As for the logical format, the DOS-FAT format is used, which is the cylindrical head sector parameter, main sector, and partition. SmartMedia also has 3.3 V and 5 V operating voltages, but it can not support both voltages at the same time. However, there are no products that use SM memory cards in the digital cameras that are now introduced.