Everything you should know about SD cards.
There is no doubt that the SD card is the most widely used memory card at present. For the vast majority of users, it is necessary to understand the relevant knowledge of SD cards.
1: size :
SD card family has three members: SD, Mini SD, and Micro SD, and the size decreases in turn. Standard SD cards are used for most cameras and cameras. Ontology has a write protection switch - but it does not affect the internal memory card, but affects the identification of card reading devices. Mini SD card has been withdrawn from the stage of history. Micro SD card, also known as TF card, is mainly used in mobile phones, motion cameras, UAVs and other products.
Dimensions of different SD cards
Micro SD cards can be converted to standard SD cards through card sets. This conversion does not slow down but may reduce system reliability (after all, one more connection). Why is a Microsoft SD card with the same capacity and approximate speed cheaper than an SD card? I'm sorry, ET hasn't found a reliable explanation.
Micro SD Card to Standard SD Card.
Micro SD card to the standard SD card holder.
There are many versions of SD cards in terms of maximum capacity. The original SD card, with a maximum capacity of only 2GB, is now out of the mainstream view (if you have a hobby for collecting old digital cameras, you may need this SD card). The most common SDHC and SDXC memory cards have a maximum capacity of 32GB and 2TB, respectively. The theoretical capacity of the newly launched SD card can reach 128TB. Uh, I wonder if I can see this full capacity SD card in my lifetime.
It is worth mentioning that SD cards (SDXC and SDUC) with 64 GB or more adopt the exFAT format, and the size of a single file can be larger than 4 GB. Recommend users who need long continuous recording and 4K high bit rate video shooting.
Capacity compatibility requires the support of devices (cameras, mobile phones, card readers, operating systems) to use large capacity SD cards (such as SDXC cards or future SDUC cards). For example, the use of SDXC cards on cameras that only support SDHC cards will result in unusable situations.
Devices that support large SD cards can use small SD cards; conversely, they cannot.
3: Speed grade:
UHS-I: Single-row contacts, the highest standard C10, U3, V30 (continuous write speed 30MB/s), theoretical speed 104MB/s. This is the main product in the current market.
UHS-II: Double-row contacts, the highest standard C10, U3, V90 (continuous write speed 90MB/s). Full duplex mode theoretical speed 156 MB/s (most cameras), half duplex mode theoretical speed 312 MB/s (card reader, etc.).
UHS-III: Dual-row contacts, the highest standard C10, U3, V90, the full duplex mode can reach 624 MB/s. However, there is no actual product yet.
The quality of the SD card is very important if there is damage, sd card picture recovery, which is more troublesome. We recommend two excellent data recovery software, iFinD Data Recovery, and Testdisk.