SDXC- Secure Digital Extended Capacity card belongs to the family of SD card association, which provides larger storage capacity and especially fast data transfer rates. It is based on SD association card specification 3.01. The latest SD card storage capacities range from more than 32GB to 2TB. The new Ultra High Speed architecture allows for improved transfer rates intended to make speeds up to a highest transfer rate of 104MB/s today and 300MB/s in the expectations.
Secured digital extended capacity card series are exclusively deliberated to meet the High Storage Capacity, High Definition Audio and Full High Definition Video necessity for the latest Digital Cameras, Mobile, DV Recorders, etc. The latest approached Speed Class enables the host to support AV applications to carry out real time recording to the Secure Digital memory card.
The SDXC specification defines two modes of functions and they are, DS i.e. Default speed mode with operating voltage of 3.3V and HS i.e. High-speed mode with operating voltage of 1.8V. The system wakes up at Default Speed mode. Whenever the system is compulsory to switch to High Speed mode then the host controller is necessary to change its working voltage level from 3.3V to 1.8V dynamically.
SDXC Card Interface
SDXC cards and host devices communicates through a synchronous one-bit interface, where the host device furnish a clock signal that blinks single bits in and out of the SDXC card. The host devices can send 48-bit commands meanwhile receives responses. The memory card can signal that a reply will be postponed, but the host device can terminate the dialogue.
Through issuing various commands, the host device can: