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Agilent Technologies' Smaller CMOS Image Sensors Enable Lower Cost Digital Camera Solutions

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Agilent Technologies announced a new family of color and monochrome CMOS (complementary metal oxide semiconductor) image sensors. The smaller sensors, supplied in a 25 percent smaller and 50 percent thinner surface-mount package than previous versions, enable the design of compact, lower cost consumer and industrial digital camera solutions. The Agilent VGA color image sensors (640 x 480 pixel) are ideal for PC cameras, detachable cameras for mobile phones and PDAs, and for digital still and dual-mode cameras. The CIF monochrome image sensors (352 x 288 pixel) are excellent choices for biometrics (identifying individual human characteristics such as fingerprints), surveillance and security, machine vision and bar code scanners. "This introduction significantly enhances our image sensor product portfolio," said Jason Hartlove, vice president and general manager of Agilent's Sensor Solutions Division. "As the CMOS image sensor market leader, we will continue to apply our IC design expertise and high-volume manufacturing to deliver products that meet the needs of our customers." Agilent's CMOS image sensors are provided in the new industry-standard 32-pin CLCC (ceramic leadless chip carrier) package. The package has dimensions of 10.7 mm x 10.7 mm x 1.65 mm compared to the 13.5 mm x 14.5 mm x 3.80 mm of the previous Agilent image sensors supplied in the PQFP (plastic quad flat pack) package. The CLCC package features a flat top and more accurate height placement due to flat pins, making optical adjustment quicker and simpler. This new package also features enhanced thermal performance assuring operating stability over a wider temperature range. These CMOS image sensors also offer high sensitivity and a low-noise design for capturing more detailed pictures in a variety of lighting conditions. The sensors offer an anti-blooming feature that prevents the whiteout of images taken with a flash, as well as low power consumption that enables more efficient power management and longer battery life. The Agilent CMOS image sensors integrate a highly sensitive active pixel photodiode array with timing control and onboard A/D conversion. These image sensors, when coupled with compatible image processors from either Agilent or selected Agilent partners, provide a complete imaging system to enable rapid end-product development for camera manufacturers. Further information on these and other Agilent image sensors and image processors is available at: Agilent Image Sensors Agilent Semiconductor Products Group Tel: 800-235-0312,

Many of you probably know Agilent as I do, from the nascent days when Bill Hewlett and David Packard started it as a test and measurement company. It has evolved from then to become so much more than a singularly focused electronics company. The products from the sensor solutions division attest to that. Take for example this new CMOS Image Sensor. It's a silicon chip with integrated analog and digital circuits. On this one chip you get an active pixel photodiode array with timing control, ADCs, and programmable amplifiers. These CMOS sensors can provide low noise images while consuming very low power. The CMOS sensor works just the opposite from a TV screen, which combines red, green and blue pixels on the screen to produce the various colors. The CMOS sensors have red, green, and blue filters on every pixel that pick up light and filter it at each pixel. Our eyes combine this into the various colors when they are reintroduced on a computer screen or LCD screen. Looking at the data sheet you may notice that two resolution formats, the VGA 640 x 480 pixels and the common intermediate format (CIF) 352 x 288 pixels are offered. Both formats are available in monochrome or color. The VGA format uses a faster clock of 30 MHz and faster frame rate of 30 fps compared to the CIF format that uses a 24 MHz clock and a frame rate of 15 fps. You might think that the 15 fps would cause the notorious flicker problem but it doesn't happen because of the interrelationship between frame rate and exposure time. For example, if you have a slower image sensor then your exposure time wonęt be as fast. So you wonęt be able to support as fast an exposure time. Of course this isn't a problem in still pictures but in video, once your frame speed goes below about 10fps you will notice a delay in the picture, which is missing information. The different offerings of clock speed and frame rate are a trade off for those customers who donęt need the higher resolution that VGA offers, or the higher expense. One of the main differences between this version and a previous CMOS sensor version is the move from a custom chip package to an industry standard CLCC package, which is also a smaller package. Good move by Agilent to make this very popular sensor even more accessible by this growing market. The target markets for the color sensor are PC cameras, digital still cameras, and detachable cameras for mobile phones and PDAs. For the monochrome sensor the market includes areas that have only blossomed in the past year, including security cameras, robotics, fingerprint sensors, and barcodes. There are a couple other advantages to using the CLCC packaging. Some camera manufacturers will find it useful that the CLCC packaging has improved thermal performance compared to the previous package. The CLCC is a ceramic rather than a plastic package, so the same amount of thermal energy going through the package wonęt heat up the sensor as much. The new package also has a flat top rather than plastic with a window. The flatness enables the manufacturer to key off any area of the package top for their assembly process. The manufacturer will have to attach a lens on the CMOS sensor, and they must position the lens at exactly the correct focal distance for the camera to be in focus. It is much easier for the manufacturer to do that if the top of the package is completely flat. Another advantage ę the new package doesn't have pins. In the old package the pins were more likely to bend when assembling the part onto the PCB. It was more difficult to get the correct Z height and therefore the correct focal distance. The new package gets rid of that pin bending problem. The optical center for VGA and CIF packages are the same. This is something new from the previous package type. The optical center is the center point of the array, and the placement of that relative to the package window. This makes it easier for manufacturers to produce a CIF and VGA version for the same type camera because they can use the same lens mount, and same lens. So the manufacturer doesn't need different lenses for different cameras ę a savings on the BOM. Finally, Agilent also made the sensors so you can customize them to fit your application. You can tweak the sensors via software including exposure, frame rate and gains of the ADC, so you can customize them for your particular camera. All of it is programmable thru an I2C port or a UART port. Agilent provides some useful tips in their data sheets including information about PCB layout and power supplies. For example, the analog Vdd and analog ground need to be routed separately from the digital Vdd and ground. The Agilent ADCS-1021 (color with CIF-resolution) and ADCS-1121 (monochrome with CIF-resolution) CMOS image sensors are priced at less than $5 in high volumes. The Agilent ADCS-2021 (color with VGA-resolution) and ADCS-2121 (monochrome with VGA-resolution) CMOS image sensors are priced at less than $7 in high volumes. All four devices are available in production volumes. Product brochures: Color CMOS Sensors Monochrome CMOS Sensors

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