Tool/software:
Hello,
I am doing some signal integrity analysis. When I connect an output of 74LVC series to an input of a device from the same series (or any other device with high input impedance), I see a large ringing at the receiver. It has been the general practice to connect them direct in the past, as well as I haven't ever observed this king of ringing in practice (monitoring via an oscilloscope). I am wondering if this is an issue with the IBIS file, a tool issue or I am doing something wrong with simulation setup. I had to have a 49 ohm source termination to get the signal quieted down (see below). I appreciate any help on this regard. If I were to use source termination, I have to add 86 resistors to my design (yes, I have 86 outputs driving other circuits directly). Below is the schematic (without and with termination) and Waveforms (without and with termination).
Thank you,
Tharaka.