LMH1981

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 SD/ED/HD video signals with either bi-level or tri-level sync, and the outputs provide all of the critical timing signals in CMOS logic, which swing from rail-to-rail (V_CC and GND) including Composite, Horizontal, and Vertical Syncs, Burst/Back Porch Timing, Odd/Even Field, and Video Format Outputs. HSync features very low jitter on its leading (falling) edge, minimizing external circuitry needed to clean and reduce jitter in subsequent clock generation stages.

The LMH1981 automatically detects the input video format, eliminating the need for programming using a microcontroller, and applies precise 50% sync slicing to ensure accurate sync extraction at O_H, even for inputs with irregular amplitude from improper termination or transmission loss. Its unique Video Format Output conveys the total horizontal line count per field as an 11-bit binary serial data 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 a temperature range of −40°C to +85°C.