SSDs are dead; long live the SSD - or something like that. Sandisk today outlined its vision for mobile devices filled with smaller versions of the Nand flash memory hard disk and cited smartbooks as the obvious device in which they will find a home.

Solid state disk drives first appeared in 2007 and were originally assumed to be natural companions to the netbook: their light weight, small footprint and lack of moving parts that could be damaged seemed to make them an obvious successor to the hard disk drive. But while high-end ultraportable laptops such as the premium model of the Apple Macbook Air and some of the first generation of notebooks came in SSD models, they haven't been widely adopted.

Sandisk expects it to be a different story with smartbooks and pico SSD (pSSD) drives. As before, they come in versions from 4GB to 64GB, but they'll be used with different hardware. 

Were smartbooks based on Windows, the level of storage pSSD offers would be laughable. Sandisk has just unveiled a 64GB iNAND chip to be embedded in devices and that is the same size as a microSD card chip. 

But smartbooks have more in common with smartphones than they do other laptops. Connectivity and portability are their main reasons for existence - and they don't require hefty apps or a desktop operating system on which to run. Instead they run Linux or Android, draw little power and have batteries that last a full day. They are also fairly inexpensive, putting them within the financial grasp of the consumer.

Doreet Oren, Sandisk's director of product marketing for SSD, cites the global recession and the expense of high-capacity SSD drives as the main reasons they haven't yet taken off for the company. But she also sees a strong case for SSD eventually coming to replace the hard disk, at least in some types of device.

The arguments for SSD are the same as they ever were, but it's the introduction of a compelling, usable mobile OS for larger-screen devices such as smartbooks that tips the balance. Screens that draw less power than previous netbooks and laptops did are also part of the equation, as is the persistent availability of web access thanks to 3G. Oren says 60 percent of netbook use is web-based. 

Oren won't offer predictions of her own for the eventual success of the pSSD, but she points to analyst predictions of 30 percent of smartbooks using them by 2012 or 2013. That's not an overwhelming prediction, perhaps, but if it's a success, it seems likely that will be in this smaller, lower-capacity iteration. And Sandisk has also won some significant customers. 

The first three devices to be publicly shown and that use pico SSD drives are the Sony X, plus models from Asus and LG. Others are also working with Sandisk but have not yet publicly played their hand.

As a co-owner with Toshiba of the Japanese fab that makes Nand flash memory for the world, Sandisk has come to the SSD market almost by default. This year is the first year Sandisk's SSD branch has been at Mobile World Congress.

Until the evolution of the smartbook, the company was primarily about memory cards for mobile phones and digital cameras. It still is, making more than a million cards every day. These, says Sandisk PR director Mike Wong, are sold in more than 100 countries and account for almost all of the 22-year-old company's annual $3.57bn revenue. But if analyst predictions are to be believed, it may just have another strong suit once smartbooks take off.