1FEATURES

2• Standard Analog Video Sync Separation for

NTSC, PAL, 480I/P, 576I/P, 720P, and

1080I/P/PsF from Composite Video (CVBS),

S-Video (Y/C), and Component Video

(YPBPR/GBR) Interfaces

• Bi-Level & Tri-Level Sync Compatible

• Composite, Horizontal, and Vertical Sync

Outputs

• Burst/Back Porch Timing, Odd/Even Field, and

Video Format Outputs

• Superior Jitter Performance on Leading Edge

of HSync

• Automatic Video Format Detection

• 50% Sync Slicing for Video Inputs from 0.5 VPP

to 2 VPP

• 3.3V to 5V Supply Operation

APPLICATIONS

• Broadcast and Professional Video Equipment

• HDTV/DTV Systems

• Genlock Circuits

• Video Capture Devices

• Set-Top Boxes (STB) & Digital Video

Recorders (DVR)

• Video Displays

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 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 (VCC 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 OH, 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.