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HDMI TMDS the issue of common mode noise

Question asked by liqiang on Nov 10, 2013
Latest reply on Nov 11, 2013 by GuenterL

Hello :

     I used the ADV7611 as a HDMI receiver in my production to output the video data to a monitor.

     It was okey.  But when I made a call using the cell phone around it , the image watching from the monitor  was wrong that looked like already lose some image data. Even worse, it might be black (nothing in the monitor) and I needed to reset the ADV7611.

     I tested the HDMI connecter and viewed the wave from the oscilloscope , there was a noise of the frequency of 900Mhz which equaled the frequency of the 2G communication network on the two line of TMDS . And I figured out that the noise as the common mode noise coupled from the communication network failed the communication of the TMDS.

     I only seriesed a ESD protector in the wire of the TMDS.

     So do you have some good advice to decrease the effect of the common mode noise. other people how to dealt with it?

     Remark Seriesed a Common mode chokes paralled a capacitor of small value. Nothing can improve.

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