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LM1881 - Video Sync Separator IC

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Pin Configuration

Pin Number

Pin Name



Composite Sync Output (CSOUT)

This is an output pin which provides the stripped out composite signal


Composite Video In (CVIN)

This is the input pin to which the video with composite is fed


Vertical Video Out (VSOUT)

This pin outputs the composite free filtered video signal


Ground (GND)

Connected to ground of the system


Burst/Back Out (BPOUT)

Outputs burst or back porch timing signal



Used to reset the IC


Odd/Even Output (OEOUT)




Powered normally with +5V or +12V


LM1881 Specifications

  • Operating Voltage: +5V to +12V
  • Can process Sync over composite,  Sync over luma and composite sync videos
  • High Input resistance and low power supply drain current.
  • Scan Rate: 150kHz


LM1881 Equivalent

EL1881, EL4581


Alternatives Video sync separators

LM1981, EL1993, EL4583


Where to use the LM1881 Video Sync Separator IC

The LM1881 is used in many video related application where composite video and RGB video is involved. One noticeable main application of the IC is to convert sync over composite videos (HSYNC + VSYNC + CVBS) into CSYNC video (HSYNC+VSYNC) by removing the composite video (CVBS) aspects. This comes in handy while using the old RGB monitors since they do not support composite sync information.

So if you are looking for a composite video conversion IC then LM1881 might be of interest to you.


How to use LM1881 IC

One big advantage of LM1881 is that it can work with minimum number of components. Along with the IC, it only requires an additional resistor and a couple of capacitors. The typical connection diagram for LM1881 is shown below.

LM1881 IC Connections

The LM1881N IC has an operating voltage from 5-12V, but normally it is operated either in +5V or +12V. The video with composite is fed to pin 2; the capacitor acts as a parasitic capacitor to filter noise. The output video which is free of composite and can be used on RGB monitors can be obtained from the pin 3.



  • Composite to RGB converter modules
  • Game consoles
  • TV set-top Boxes
  • Entertainment systems
  • Video cameras


2D-Model (PDIP)

LM1881 IC Dimensions