SanDisk has unveiled its TrustedFlash MicroSD memory cards at the CTIA Wireless IT and Entertainment tradeshow in San Francisco.

The storage cards include embedded digital rights management (DRM) and decryption technology, as well as a subscription manager allowing them to be used for digital music and subscription music services.

SanDisk will keep control of TrustedFlash for now, but said that it expects to open up the technology as it matures and gains support from the industry.

MicroSD memory is used in many mobile phones, including the Motorola Rokr and the Nokia 3250 music phones. Incorporating DRM directly onto the chip allows it to be used as a content holder similar to a CD or DVD.

Digital content today is often limited to one device or requires a computer to be moved around. Apple's iTunes music content, for instance, can be played on a limited number of computers.

Because the SanDisk DRM technology is embedded on the chip that also holds the actual content, the user can move it between devices.

"Today content is locked to play back on one device. Now we have the freedom to enjoy content on whatever device consumers want to use," said SanDisk chief executive Eli Harari at the unveiling.

Record labels and games developers are expected to release content stored on TrustedFlash memory cards.

The latest Rolling Stones album is scheduled for release in November in a format that holds four additional albums that can be unlocked after the consumer buys the music. The chip with the first album will sell for $39.95. 

Pedro Vargas, manager for mobile entertainment at SanDisk, told vnunet.com that the content will play on smartphones running Palm OS or Windows Mobile.

In the future the chip should also enable users to download content directly from the internet onto their mobile devices, as well as play content from subscription music services such as Yahoo Music and Napster.

Yahoo Music is a SanDisk partner in TrustedFlash, but for now only supports play back of music sold preloaded onto memory chips and will not allow the use of TrustedFlash to transfer content from the subscription service.

Harari also pointed out that TrustedFlash could enable new business models for content creators, such as limiting the number of times that a consumer can listen to a song or offer a free one-time preview play.