LMH1981 Datasheet | National Semiconductor

Description The LMH1981 is a high performance multi-format sync separator ideal for use in a wide range of video applications, such as broadcast and professional video equipment and HDTV/ DTV systems. The input accepts standard analog video signals with either bi-level or tri-level sync, and the outputs provide all of the critical timing signals in CMOS logic, including posite, horizontal, and vertical syncs, burst/back porch timing, odd/ even field, and video format outputs. The horizontal sync output features very low jitter, minimizing external circuitry needed to clean and reduce jitter in subsequent sync processing stages. The LMH1981 automatically detects the input video format, eliminating the need for programming using a microcontroller or external RSET resistor. The sync separator applies precise 50% sync slicing to ensure accurate sync extraction for inputs with irregular amplitude, offset, and noise conditions. Its unique video format feature (pin 9) outputs the total vertical scan lines per frame as an 11-bit binary serial bit stream, which can be decoded by the video system to determine the input video format and enable dynamic adjustment of system parameters, i.e.: color space or scaler conversions. The LMH1981 is available in a 14-pin TSSOP package and operates over the full mercial temperature range. Features n Standard analog video sync separation for NTSC, PAL, SECAM, 480i/p, 576i/p, 720p, 1080i/p, and RGs B from posite (CVBS), S-Video (Y/C), ponent (YPBPR), and puter video interfaces n Bi-level & tri-level sync patible n posite, horizontal, and vertical sync outputs n Burst/back porch timing, odd/even field, and video format Outputs n Superior jitter performance on the H Sync negative-going edge reference n Automatic video format detection n 50% sync slicing of video inputs from 0.5 VPP to 2 VPP n Macrovision patible n 3.3V to 5V supply operation Applications n n n n n n Broadcast and professional video equipment HDTV/DTV systems Genlock systems...