Faster speeds, more mobility, and greater power efficiency expected to begin hitting designs next year

Universal Serial Bus is about to get faster, more versatile—and far more ubiquitous.
Jeff Ravencraft, chairman of the USB Implementer’s Forum and a technology strategist at Intel, provided a glimpse of the upcoming roadmap that includes three separate efforts. The first effort is to clean up problems with existing versions and make them more efficient. The second effort will focus on speeding up the standard through Superspeed USB. The third effort is focused on wireless USB. All of these efforts will be rolled out over the next couple of years as the standard continues to make inroads into all electronics.

“USB is the most successful interface in history,” Ravencraft told attendees at a Synopsys’ Experts on the Road IP Seminar recently. Ravencraft said the next step would be to focus on power, both in terms of USB’s efficiency and its ability to charge devices. “When we first designed USB 2.0, than there was not the focus on power there is today. But power in portable devices is the number one thing that has to be delivered.”

The problem now is that the host constantly is sending calls out to the device through the USB interface asking if there is traffic; this requires power on both sides. Ravencraft said that would change in future versions of USB to allow the devices to power down when there is no traffic. This change will be combined with new functionality, such as the ability to charge more devices over USB, and the ability to have devices trade off between being the host or being a device connected to the host. For example, a car stereo or a set-top box will be able to act as either a host or the connected device to another host, such as an MP3 player.

Superspeed USB 3.0, first announced at the Intel® Developer’s Forum last fall, will begin showing up in product designs in 2009, propelled by a standards promotion group established last fall by such heavyweights as Intel, HP, NXP, NEC, Microsoft and Texas Instruments. The new standard will allow a 27-Gbyte high-definition movie to download in 70 seconds, compared to 13.9 minutes using USB 2.0 and 9.3 hours using USB 1. Under the new standard, a 4-Mbyte song can be downloaded over USB 3.0 in .01 seconds, compared to .1 seconds using USB 2.0 and 5.3 seconds using USB 1.0.

Ravencraft said there are more than 160 companies contributing to the USB 3.0 specification at the moment. He said the next step would be to move into the adopter stage with broad deployment of USB 3.0 expected in 2010.

Ed Sperling is a regular contributing editor to Chip Design magazine. Ed has spent the past two decades immersed in technology. He is the recipient of numerous awards for journalistic excellence.