how to use the eyeDiagram function in spectre?

[newbie_1]

spectre ocean time

hi,

Can anyone tell me how i can use the eyeDiagram function in the calculater in spectre? suppose i have a waveform with period of 500ps and dutycycle of 60%.

thanks
newbie

 

[darkk]

spectre eye calculation

From the wafeform window (I assume awd here), clikc the "calculator" and then go to "special functions" and then clik "EyeDiag". Here you go!
For details, you need hit the manual of "calculator" of Cadence.

 

[newbie_1]

cadence eyediagram function

hi darkk,

thank u for ur reply, i have done that,but anyway i have set the start and end points and the period, but still i cannot get the eye diagram expected.

newbie

 

[newbie_1]

spectre eyediag

anybody help me??

 

[safwatonline]

spectre eye digram

hello,
i need to know this too plz,
anyway i think if u want it fast, u may try use transient analysis while using a saw-tooth source which u may adjust as ur period , make it x-axis
it is just a suggestion , and i didnt try it.
regards,
a.safwat

 

[newbie_1]

eye-diagram eyediag

hi safwatonline,

i dont catch what u mean, can u elaborate it more clear?
thanks a lot

newbie

 

[safwatonline]

plot eye diagram in spectre

hello,
i mean u could make the eye-diagram as if u are usig a cro,
add a pulse source and adjust its period rise and fall time and pulse width to appear as a saw-tooth signal with the same period as ur signal,connect this source to a dummy load.
run transient analysis and plot both ur signal and source.
choose to plot ur signal vs. the saw-tooth.
this might work but it has some problem as the signal will be plotted with the saw-tooth all the time, which will lead to a drawn line with the fall time of the saw-tooth which we dont want ,
if u can live with that line try it.
regards,
a.safwat

Added after 8 seconds:
again i didnt try it , so i am not sure that it will work, btw u could take the signal from the cadence tool as data using ocean ,and plot the eye diagram using matlab

 

[newbie_1]

how to plot eye diagram spectre

hi safwatonline,
thanks a lot,
then how can i dump the data using ocean?

newbie

 

[safwatonline]

eyediagram cadence

hello,
about taking data to a file using ocean u can use the command ocnPrint , i attached the discription of this command from the cadence documentation.
regards,
a.safwat

 

[littlelab]

Re: plot eye diagram in spectre

This is a good way to solve the problem. However, i found that the x-axis turns to be [v] unit instead of unit. How to solve this?

Thanks!

hello,
i mean u could make the eye-diagram as if u are usig a cro,
add a pulse source and adjust its period rise and fall time and pulse width to appear as a saw-tooth signal with the same period as ur signal,connect this source to a dummy load.
run transient analysis and plot both ur signal and source.
choose to plot ur signal vs. the saw-tooth.
this might work but it has some problem as the signal will be plotted with the saw-tooth all the time, which will lead to a drawn line with the fall time of the saw-tooth which we dont want ,
if u can live with that line try it.
regards,
a.safwat

Added after 8 seconds:
again i didnt try it , so i am not sure that it will work, btw u could take the signal from the cadence tool as data using ocean ,and plot the eye diagram using matlab