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NATIONAL SEMICONDUCTOR EXPANDS IMAGING PORTFOLIO WITH FIRST IN A SERIES OF HIGH-PERFORMANCE, LOW-POWER CMOS IMAGING SENSORS

September 25, 2000 - In a move to expand its role as a leading supplier of analog and mixed signal IC solutions to the imaging market, National Semiconductor (NYSE:NSM) today introduced a new series of CMOS imaging sensors designed to produce brighter pictures, smoother video sequences and longer battery life in cell phones, PC cameras, digital still and dual-mode cameras. The LM9627 (color) and LM9617 (monochrome) CMOS imaging chips, with integrated 12-bit ADCs, are capable of capturing still or full-motion video images up to 30 frames per second and converting them to a digital datastream. The ICs consume just 90mW of active power at full frame rate when operating from a 3.3V supply, and 80mW when in a power management mode.

"With the many developments during the past five years in CMOS sensing, it is now a highly flexible, power-efficient and cost-effective alternative to CCD technology," said Jitesh Vadhia, director of National’s Data Conversion Systems group. "Of even greater importance is the fact that CMOS imaging is the technology of choice for a rapidly growing number of new embedded imaging applications in computing and communication devices, cell phones, notebooks, PDAs, and information appliances. National’s unique imaging sensor technology will be leveraged into a family of planned solutions for these exciting emerging markets."

LM9617/27 Product Features
National’s image array uses a 7.5 micrometer square pixel and offers a total array of 664 x 504 pixels and active area of 640 x 480 pixels. The surrounding black pixels are provided for automatic black level calibration. The unique sensor core architecture attains a high fill factor of 47% without the aid of micro-lenses, resulting in a very high sensitivity level up to 11kLSBs/lux.sec. In monochrome applications, the LM9617, with additional sensitivity boosting micro-lenses, can significantly improve the performance of security cameras and machine vision at low light levels or in the IR-range while still operating at high speeds up to 30 frames per second. The high sensitivity of both parts, coupled with a high linear dynamic range of 60dB for the complete sensor response and the 12-bit ADC resolution, provides sharp, brilliant still and motion images in a variety of conditions.

National’s leading Analog Front End (AFE) architecture, with noise cancellation techniques using Correlated Double Sampling (CDS) and Programmable Gain Amplifier (PGA) circuits, produces noise-free images at very low light levels.

The 12-bit datastream from the ADC can be reformatted into 8-bit or 10-bit datastreams, making it compatible with any currently available digital image processor. Moreover, a fully programmable on-chip timing and control system offers a very high level of design-in support, allowing digital image processors to either control and read out data from the CMOS image sensor (sensor slave mode) or to receive the already formatted data from the sensor (sensor master mode).

The timing and control system is programmable via an I2C interface. Programmable timing and control system functions are automatically synchronized, allowing the user for instance to set windows of any size and any position within the active array of the image sensor, and to zoom-in on a particular area of interest. Reducing window size will also increase the frame rate.

Sub-sampling functions allow the user to preview the image with scaleable thumbnail scans. Two read-out modes - video and snapshot - can be used to control the datastream into the digital image processor. With full control of gain, exposure time and frame rate, users can tailor the sensor configuration according to their application needs and manage the sensors power consumption at different light levels.

For additional information including datasheets and evaluation systems, please contact National’s Design Support Group at 1-800-272-9959.

Price and Availability
The LM9617 and LM9627 are available now in a 48-pin standard optical LCC package. The LM9617 and the LM9627 are priced at $19.50, both in 1000-unit quantities.

About National Semiconductor
National Semiconductor provides system-on-a-chip solutions for the information age. Combining real-world analog and state-of the-art digital technology, the company's chips lead many sectors of the personal computer, communications, and consumer markets. With headquarters in Santa Clara, California, National reported sales of $2.1 billion for its last fiscal year and has about 10,500 employees worldwide. Additional company and product information is available on the World Wide Web at www.national.com.