TOKYO After more than a year of stealthy preparation, startup Y Media Inc. has come out of hiding to trumpet a 3-million-pixel CMOS image sensor that aims for nothing less than dethroning the charged-coupled devices (CCDs) that are the heart of today's most advanced digital still cameras and digital video cameras.
One of the few to develop a low-power CMOS sensor with such a high pixel count, Y Media is betting the combination of high resolution and proprietary low-noise technology will usher in a new class of cameras capable of high-quality video and still images.
"We can finally show that CMOS imagers will displace CCDs," said president Ian Olsen, founder and chief executive officer of Y Media (Irvine, Calif.). "We'll enable companies to go from discrete to hybrid cameras that can do digital stills and video. What's also important is that we're going up in resolution."
Based on 0.25-micron design rules, the company's YM-3170A CMOS sensor has a 2,056 x 1,544 pixel array (2,048 x 1,536 visible) on a half-inch format. Each pixel is 3.3 x 3.3 microns the smallest among available CMOS sensors, the company said. Sampling will begin in November, and Y Media officials said they expect consumer electronics companies in Japan to ship first products with the sensors early next year. Y Media said the cost will be competitive with imaging devices capable of similar resolutions.
Y Media is touting several architectural innovations that allow it to combine pixel processing with analog functionality on its CMOS sensor, though company officials declined to elaborate on the device's unique architectural features. Y Media does not have any U.S. patents registered, but has several pending, Olsen said.
One of the chip's best attributes is noise performance, a nagging problem for CMOS imagers that has prevented some designs from migrating down the process technology curve. Y Media, however, claims it has developed an architecture and process technology recipe that actually surpasses the noise performance of CCDs. The company declined to reveal its noise benchmarks, however.
With noise in check, Y Media said it was then free to work on features to enable full-frame rate video. "For CCDs to run at high frame rates, the noise goes up proportionally to the frame rate," Olsen said. "Ours is flat from 1 frame per second to 30 frames per second. And our imagers will go to 120 frames per second."
"With CCDs the charge is dumped down the line to one single output amplifier, and that's the noise bane of a CCD," said Greg Urban, founder and vice president of marketing and sales for Y Media. "In CMOS it can be put anywhere and optimized so that there's no heavy-duty swing with a single output amplifier."
Y Media officials declined to explain how the charge can be handled better in CMOS, though they suggested there could be places to dump the charge in various regions of the chip. "In CMOS, we can make intelligent columns and rows that can compensate for the noise and provide for added features to enhance the pixels in a lot of ways," Olsen said.
Another benefit of low noise is that it allowed Y Media to use a more advanced 0.25-micron process technology, which it developed with foundry partner Taiwan Semiconductor Manufacturing Co. Ltd. The process allows Y Media to pack more pixels onto one chip, in contrast to other CMOS imager sensors that must use design rules no finer than 0.5-micron to ensure good noise performance, Olsen said.
The company claims the combination of low noise and high pixel count enables full-frame video with a 4:3 aspect ratio that approaches film quality. The device can also be programmed to handle different aspect ratios like 3:2 and the 16:9 HDTV format, as well as features like stabilization, pan and zoom. In addition, the sensor is capable of VGA (640 x 480-pixel) resolution sub-sampling when previewing an image or video on an LCD.
Y Media plans to publicly demonstrate the sensor's capabilities here on Sept. 14.
Because the chip uses CMOS technology, Y Media was able to integrate functions that are normally handled by companion ASICs or processors. These include timing generators, voltage regulators and sub-sampling processors. Moreover, use of CMOS results in a big reduction in power consumption compared to a CCD, which can burn up to 1.5 watts of power, while the YM-3170A maxes out at 120-milliwatts, Olsen said.
Founded in March 1999, Y Media claims to have an experienced team of researchers and engineers who collectively have designed 150 imagers while working in previous positions. Many of its 38 employees come from defense and aerospace companies like Lockheed, Ford Aerospace, Hughes and JPL. Founders Olsen and Urban, as well as Japan regional director Norio Tsuruta, hail from Conexant, which designs and produces its own CMOS image sensors.
Even with these attributes, Y Media is likely to face stiff competition in Japan, where it hopes to establish a market position. Many well-known suppliers of digital cameras also design and sell image sensors Matsushita, Sony and Sharp. Others, like Canon and Fuji Photo Film, often design their own high-resolution image sensors. Canon, for example, announced a new camera with its own 3-million pixel CMOS sensor, while Olympus unveiled a CCD camera with 4-million pixel resolution.
Y Media officials remain confident, saying they already have a number of undisclosed top-tier companies that will design in their sensor for products coming out early next year. To kick off manufacturing and bring up engineering services in Japan, the company recently secured $7.5 million in second-round venture capital funding from Enterprise Partners, TechFund Capital and Chase Capital Partners.