Sync separator tailored for high-definition video formats

National Semiconductor Corp. introduced the LMH1981, a multi-format video synchronization separator with jitter performance for high-definition broadcast and professional video systems. The product is said to perform 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.

The device features the timing outputs for video systems, including horizontal, vertical and composite sync, odd/even field, burst/back porch clamp and a patented automatic video-format detection feature. It accepts both bi- and tri-level sync video inputs and features 50 percent slicing for the separation of signals that vary in amplitude, offset and noise.

The LMH1981 can accept video signals from composite (CVBS), S-video (Y/C), component (YPbPr) and computer interfaces. It auto-detects the input format 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 11bit 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.

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. Currently sampling, the LMH1981 is available in a TSSOP-14 package and will be priced at $3.79 in 1,000-unit quantities.