Next-Gen SD Format Nearing Completion: 300MB/sec Transfer Promised

We've already heard of SDXC--in fact, it's a format that was announced almost a year ago now--but we've really seen nothing to make us believe it (or the technology behind it) was ready for primetime. Now, however, it looks as if the underpinnings are finally coming together, and we're hearing things that are making us smile about existing Secure Digital options as well (backwards compatibility, anyone?)

Reportedly, the next-generation Secure Digital (SD) memory card standard, SD Specification Version 4.00, is expected to be completed by the Spring of 2010, which could mean that SDXC cards will be available for purchase in early-to-mid 2010. Why should you be excited? With new crops of DSLRs shooting high-definition video, the need for quicker cards is more dire than ever. The existing limit of 104MB/sec transfer rate is looking mighty slow at this point, but the new specification will pave the way for 300MB/sec transfers. That's almost a 3x jump, and it's a leap that should be noticeable in almost any application.

The plan is to institute a new pin and a new transfer scheme in order to boost rates. The parallel technology that is currently used will be upstaged by a serial transfer technology, which will also be made available for use in SD Input/Output (SDIO), with the objective of making it possible to use the SD bus as the internal bus for embedded systems. The goal there is to target mobile phones, which will also be able to use the faster speeds when transferring images and videos shot with their increasingly large sensors.

The best part of all this (as if a 3 jump in speed wasn't awesome enough) is that the overall size and form factor of these ultra-fast SD cards will remain as they are, and the parallel pins will remain in place as well. That means that (at least theoretically) SDXC cards could be used, read, and written to within older SD card readers, albeit at slower rates. The only challenge is to ensure that no cross-talk occurs by having two transfer schemes within a single card, but if the folks designing USB 3.0 figured it out, we see no reason why SD engineers can't.