Tuesday, July 17, 2007

Pause TV is coming

MANHASSET, N.Y. — Get ready for Pause TV, a television receiver equipped with flash memory that lets TV viewers to pause for a fridge break or rewind in mid-broadcast for instant replays.

A new TV prototype capable of pausing live TV broadcasts without the use of a hard disk drive is about to debut, according to industry sources, as early as next month at IFA, the world's largest consumer electronics trade show in Berlin. Commercial products are expected to reach the consumer market later this year or early 2008.

Without revealing manufacturers currently developing Pause TV, several consumer chip vendors have told EE Times that Pause TV represents a new product category that is being promoted to the current TV market. Magnum Semiconductor already has a Pause TV reference design and is talking with several customers, according to the company.

"A pause TV won't record a full movie, but it enables 'pause' and 'replay'—some of the most popular functions of today's personal video recorders" (PVR), said Magnum CEO Jack Guedj. Added Mark Singer, Magnum's director of corporate marketing: "Pause TV will add to the TV set the first new, everyday feature in a long time."

While Mobilygen has yet to launch a Pause TV reference platform, Chris Day, senior vice president sales and marketing at Mobilygen, acknowledged that it plans to offer OEMs a platform with several memory options, including flash memory, DRAM or hard-disk drives.

The Pause TV concept is not new. Day said CE manufacturers have contemplated Pause TV, but for various reasons haven't yet brought it to the market.

Now, two factors favor its introduction: the rapidly sinking price of flash memory and and a new generation of codecs like H.264, that can transcode the video stream and store more video into a limited flash memory.

Integrating flash memory into a TV isn't a technical problem, but a closer look at its implementation reveals several thorny design issues. The least of these is choosing the right kind of flash memory, and figuring out how much memory is needed. "It's determined by a number of variables," said Singer, including: the life expectancy of a TV set and the flash memory (measured in write cycles); how much pause time is enough; how often the same memory cell can be rewritten; and the video bit rate used for storage.

The crux of the issue is memory life expectancy. In a Pause TV application, each second of viewed broadcast TV needs to be written to flash since the system doesn't know when a user might hit the pause button. Typically, flash memory doesn't last as long as a TV. Moreover, wear and tear on a flash memory inside a TV is determined by how many hours per day a family watches TV, and how long the set is expected to last. Combining statistics on typical household TV use compiled by the U.S Energy Star program and Consumer Electronics Association and Nielsen survey, Magnum set a lifetime target for its Pause TV design of "10 years when a TV is on for 5.5 hours per day—2,000 hours per year," said Singer.


Two types of NAND flash memory are candidates for Pause TV: multilevel cell (MLC) and single-level cell flash (SLC). MLC is said to be capable of 10,000 writes per cell, with 100,000 writes for SLC. Although SLC lasts longer, it's as much as 30 percent more expensive.

Four-gigabyte MLC flash, when video is recorded at 9.4-Mbits/second (fixed-bit rate at full-DVD quality) yields 60.9 minutes of buffered TV—the maximum possible for a Pause TV application. According to Magnum, that translates into a life-expectancy of 5.1 years. "This is a solution that we would reject," said Magnum's Singer.

Instead, Magnum is proposing either doubling the flash or reducing the bit rate of the encoded video by about one half. That would allow it to deliver Pause TV with a 10-year life expectancy while doubling available pause time. For example, when a variable bit rate averaging 4.5 Mbits/second (standard definition broadcast TV quality) is applied, 4-Gbyte MLC flash delivers 127.3 minutes of pause time. That works out to a life-expectancy of 10.6 years, said Singer.

Magnum's reference design consists of a TV tuner, DVB-T (European DTV standard) demodulator, MPEG-2 encoder, DRAM associated with MPEG-2 codec along with flash and input/output for digital and analog TV signals.


If a future Pause TV reference design includes H.264, the amount of flash can be reduced further. That's where Mobilygen hopes to enter the market with its latest H.254 codec.

Magnum also made a move in the market recently when it acquired LSI Logic's consumer chip business. The deal underscores Magnum's ambition to advance its reference design by adding H.264 codec and an ATSC (the U.S. DTV standard) demodulator. LSI Logic had already developed both.

Marketing issues remain


Still, fundamental marketing issues remain for Pause TV, said Michelle Abraham, principal analyst at In-Stat. "Many U.S. consumers already have Pause TV functions in cable or satellite set tops integrated with PVR. Will consumers still want that pause function embedded in a TV? If so, at what cost?" Abraham said. "It may be hard to get consumers to understand what the Pause TV does, and why they need to pay extra $50."

Mobilygen's Day acknowledged that Pause TV could be a regional product, faring best in "free-to-air" TV markets in Europe and Asia, he added.

Magnum estimates the addition of Pause TV functions to a current DTV design will cost about $40 when implemented as a "bolt-on" solution. But there are many duplicate DTV functions with Pause TV, said Singer, including the MPEG-2 decoder already inside a DTV and associated memory. An integrated DTV/Pause TV solution, "can bring the cost down," he claimed.

Consumer chip vendors and system companies are also considering other Pause TV design options. One approach is adding a slot for a USB stick that would allow TV set vendors to reduce their bill of materials and market sets as "Pause-TV ready."

Meanwhile, several Japanese manufacturers are pushing a removable hard drive for TVs. An HDD-based PVR solution may prove difficult, according to Singer. "It's much easier to implement simple pause and instant replay functions on a TV," he said.