Passive equalizer + digital amplifier

[brianguy]

site:edaboard.com equalizer

Hi everyone. I have a question as follow:

It is well known that the lossy transmission line will induce non-negligible ISI effect on the transmitted digital signal. When a passive equalizer is employed, the ISI effect will be reduced, but inevitable DC-loss will lower the voltage level of signal. For example, the original voltage level is between 0~0.4V. After using the passive equalizer, the voltage level becomes 0~0.2V. If I want to use an "simple" amplifier to enhance the voltage level to the original 0~0.4V, what kind of amplifier circuit should I choose? Can anyone answer this question? Thank you very much

 

[sunjimmy]

You don't need to amplify the signal again. Just pass the equalized signal to high speed comparator, you will get back the original digital signal.

If you still want to amplify the signal, I suggest that you can use simple PMOS differential pair ckt with resistative load.