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Pre-emphasis: voltage swing

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circuitking

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Hi

In LVDS output swing in the transmitter is -350 mV to 350 mV. After doing the pre-emphasis, is the swing going to be increased (Vpp in the image below)?. As per the image below it seems to me that the maximum limits are not going to change. What happens to the signal content marked Vs?. its swing is going be smaller than -350 mV to 350 mV, doesn't it degrade the signal quality at the receiver?.

pre.jpeg


From: https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/wp/wp_pre-emphasis.pdf


Edit:

In the document it says
"It is necessary to select the optimum settings for both pre-emphasis and equalization. Over compensation can cause additional issues within the system. It will add extra jitter which will close the eye making it impossible for the receiver to interpret the information".

How do we know how much is over compensation, do we just have to look at the eye diagram at the receiver/transmission and decide or is there any rule of thumb?
 
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In the document it says
"It is necessary to select the optimum settings for both pre-emphasis and equalization.

The receiver is the chief priority, so as to assist interpretation of the signal.
I think the document means that pre-emphasis and equalization need to be adjusted for the receiver's individual characteristics.

I picture dialing a potentiometer(or two potentiometers, one for pre-emphasis, one for equalization). Dial toward minimum, then toward maximum, to find a midway position which yields optimum reception.
 

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