National Semiconductor debuts industry’s lowest-jitter sync separator for High-Definition video formats

SANTA CLARA, Calif. – National Semiconductor Corporation (NYSE:NSM) has introduced a multi-format video synchronization separator with the industry’s best jitter performance for high-definition broadcast and professional video systems. The LMH1981 allows video designers to accurately and precisely extract horizontal and vertical sync signals without extra filtering and jitter-cleaning stages.

The LMH1981 performs all the necessary sync separation to generate low-jitter horizontal and vertical sync signals for NTSC, PAL, SECAM, standard and high-definition video formats, including 480i, 480p, 576i, 576p, 720p, 1080i and 1080p. It features the timing outputs needed for any video system, including horizontal, vertical and composite sync, odd/even field, burst/back porch clamp and a patented automatic video-format detection feature. The device accepts both bi- and tri-level sync video inputs and features 50 percent slicing to ensure accurate separation of signals that vary in amplitude, offset and noise.

Advanced Video Sync Detection
The LMH1981 can accept video signals from composite (CVBS), S-video (Y/C), component (YPbPr) and computer interfaces. It auto-detects the input format, eliminating the need for external programming using a microcontroller, and applies the proper 50 percent sync slicing methodology. Its automatic video format detection feature outputs the total vertical resolution or line count through an 11-bit binary data stream. The output pin specifies the video format detected at the input and can be used to inform the video system of any format change to dynamically adjust system parameters, like color space or scalar conversions.

Reduced System Jitter
Based on input-referred jitter testing of high-definition video inputs, the LMH1981 yields up to a 30 percent improvement in output horizontal-sync jitter when compared to current solutions. This improved performance gives designers the flexibility to use smaller field-programmable gate arrays (FPGAs) and reduces the number of external circuits needed for jitter cleaning. Many systems today use multiple stages or FPGAs after sync separation to clean and filter jitter before taking the sync pulses into a phase-lock loop (PLL). The LMH1981 minimizes the need for external jitter cleaning elements and makes it easier for manufacturers to build systems with more accurate house and reference clocks.

The chip operates on single supply voltages between 3.3V and 5V, and is compatible with the Macrovision Video Copy Protection System commonly used in VHS and DVD video sources.

National at NAB
At NAB in Las Vegas from April 24 to 27, National will demonstrate the LMH1981 sync separator in Room SU05-MR on the second level of the South Hall. To schedule a meeting, media interview and/or to see demonstrations of National’s new video chip, please contact Naomi Mitchell at 408-721-2142.

Pricing and Availability
Sampling now, the LMH1981 is available in a TSSOP-14 package and will be priced at $3.79 in 1,000-unit quantities. For more information, easy-to-order samples and an evaluation board, visit A large selection of amplifiers is supported by National’s Amplifiers Made SimpleSM WEBENCH' online design tool. To explore these solutions, visit To learn more about designing with amplifiers, visit the library of online seminars at

To view a high-resolution, downloadable photo of this product, visit National's

Solutions Supporting Video Systems
National’s analog technology can help video engineers differentiate their products. In addition to its high-performance, high-speed amplifiers, National provides the key functions every system engineer requires in power management, data conversion, interface and serial digital video products, audio subsystems, display ICs and networking products.
About National’s Amplifier Portfolio
Specializing in high-performance amplifiers and comparators, National Semiconductor offers a complete portfolio of op amps addressing the high-speed, precision, low-voltage and low-power markets with products ranging from building-block chips to application-specific standard products (ASSPs). The company has a long history of setting industry standards in amplifiers and continues this trend with product releases on National’s advanced VIP10 bipolar and VIP50 BiCMOS processes. National also leads the industry in packaging technology with its revolutionary Silicon Dust™ and micro SMD packaging technologies. For more information on National’s amplifier products, visit

About National Semiconductor
National Semiconductor, the industry's premier analog company, creates high-value analog devices and subsystems. National's leading-edge products include power management circuits, display drivers, audio and operational amplifiers, communication interface products and data conversion solutions. National's key analog markets include wireless handsets, displays and a variety of broad electronics markets, including medical, automotive, industrial, and test and measurement applications. Headquartered in Santa Clara, California, National reported sales of $1.91 billion for fiscal 2005, which ended May 29, 2005. Additional company and product information is available at

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