Capacity (SD/SDHC/SDXC)

There are three standards for capacity :

SD standard - Up to 2GB SD memory card using FAT 12 and 16 file systems.

SDHC standard - over 2GB-32GB SDHC memory card using FAT32 file system.

SDXC standard - over 32GB-2TB SDXC memory card using exFAT file system.

Card form factor

SD : 32 x 24 x 2.1 mm, Approx 2g.

 

mini SD : 20 x 21.5 x 1.4 mm, Approx 1g.

 

micro SD : 11 x 15 x 1.0 mm, Approx 0.5g.


 

What is UHS ?

UHS stands for 〝Ultra High Speed〞 and refers to the new technology that enables higher bus interface speeds on Secure Digital High Capacity (SDHC) and Secure Digital Extended Capacity (SDXC) cards.

Speed Class and UHS Speed Class* symbols indicate minimum writing performance to ensure smooth writing of streaming content such as video shooting. This is important mainly for camcorders, video recorders and other devices with video recording capabilities.

Speed Class designates minimum writing performance to record video. The Speed Classes defined by the SD Association are Class 2, 4, 6 and 10.

UHS Speed Class is designed for UHS** devices only and designates minimum writing performance to record video on UHS products.

* (Speed Class and the UHS Speed Class are two different ratings.)
**UHS (Ultra High Speed), the fastest performance category available today, defines bus-interface speeds up to 312 Megabytes per second for greater device performance. It is available on SDXC and SDHC memory cards and devices.

	Marks	Operable Under	Applications	Speed
Speed Class		High Speed Bus I/F	Full HD video recording HD still consecutive recording	≥10 MB/s
		Normal Bus I/F	HD ~ Full HD video recording	≥6 MB/s; ≥4 MB/s
			SD video recording	≥2 MB/s
UHS Speed Class		UHS-I Bus I/F	Full higher potential of recording real-time broadcasts and capturing large-size HD videos	≥10 MB/s