1 

     2 ==========

     3  SD cards

     4 ==========

     5 .. contents::

     6    :local:

     7 

     8 Standards

     9 =========

    10 

    11 ======= =========== ====== ======= =============== ==================

    12 Acronym Capacity    FS     Spec    Compatibility   Name

    13 ======= =========== ====== ======= =============== ==================

    14 SD      128MB-2GB   FAT16          SD, SDHC, SDXC

    15 SDHC    4-32 GB     FAT32  SDA 2.0 SDHC, SDXC      High Capacity

    16 SDXC    64GB-2TB    exFAT  SDA 3.0 SDXC            Extended Capacity

    17 ======= =========== ====== ======= =============== ==================

    18 

    19 Ultra High Speed, Phase I (UHS-I):

    20 * 50MB/s (UHS-50)

    21 * 104MB/s (UHS-104)

    22 

    23 Ultra High Speed Phase II (UHS-II):

    24 * 156MB/s

    25 * 312MB/s

    26 

    27 Speed

    28 =====

    29 

    30 SD Speed Class:

    31 

    32 ====== =========

    33 Class  Min Speed

    34 ====== =========

    35 2      2MB/s

    36 4      4MB/s

    37 6      6MB/s

    38 8      8MB/s

    39 10     10MB/s

    40 ====== =========

    41 

    42 UHS Speed Class:

    43 

    44 ====== =========

    45 Class  Min Speed

    46 ====== =========

    47 1      10MB/s

    48 3      30MB/s

    49 ====== =========

    50 

    51 https://support-in.wd.com/app/answers/detailweb/a_id/36273/~/specifications-and-compatibility-for-sd%2Fsdhc%2Fsdxc-memory-cards

    52   Specifications and Compatibility for SD/SDHC/SDXC Memory Cards.

    53