SDHC® is the new designation for Secure Digital cards exceeding 2GB in size. The HC series adheres to the SD Specification Version 2 which allows the cards to reach 32GB in size.
Aside from the larger storage capacity, SDHC cards offer optimized recording performance with support for FAT32 file formats. The SD Association has defined 3 speed classes in order to identify speed and performance capabilities of the SD/SDHC cards and the host products. The SD speed Class Ratings specify the minimum sustained write speed for SDHC cards, as follows:
Class 4 : 4 MB/s
Class 6 : 6 MB/s*
SDHC-compliant cards have both the SDHC and Speed Class logo in their packaging.
Though SDHC cards are identical in size with the standard SD card, only SDHC-compatible products will be able to accept the newer SDHC cards. SDHC host products can use both SD and SDHC memory cards, while SD host products can use only SD memory cards of 2GB or lesser size.
*1 megabyte (MB) = 1 million bytes
Note: SDHC, the SDHC logo and SD are trademarks
