Verifing Tpd in GreenPAK simulation in nano second resolution

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rsbogdan
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Verifing Tpd in GreenPAK simulation in nano second resolution

Customer needs sub-200ns Tpd for the Propogation delay and per the data sheet this can be achieved --Table 2 on  Page 11 (PDF page 13) of the data sheet indicates that the SLG46170 can do this without much issue.

Since this is a new part, they wanted to verify these delays in Simulation. However, it looks like the Simulation can only be able to give a resolution down to 1us. Depending on the rise time of the input, they do see a different Tpd. Can the GreenPAK simulation be enabled show the Tpd down to nanoseconds as specified in Table 2 ?

Device: 
Device Number: 
SLG46170
olehs
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rsbogdan, 

rsbogdan, 

 

Thanks for your question, 

Could you please clarify the term "Simulation resolution". Could you send me the design with the Simulation settings

If you want to scale the simulated plot you can hold CTRL and scroll the wheel, until see the propagation timings

 

Best regards, 

olehs

 

rsbogdan
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Last seen: 1 year 9 months ago
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The Simulation appears to

The Simulation appears to only be able to give a resolution down to 1us. Depending on the rise time of my input, I see a different Tpd. That's why I have two projects. One has a user defined input. The other project used their built in clock.

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olehs
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rsbogdan, 

rsbogdan, 

Now I see what you mean, yes, there is a limitation on the resolution when you use "Clock generator". The signal rump is set by the simulation and we can't control it. That's why we recommend to use Trapeze genarator (or Custom signal as you used in "project" file), where you can set the rump (either rising or falling) by yourself. 

The reason why you didn't see the propagation timing when you appiled the signal with a long rump is that the Vih and Vil of PINs are equal ~0.7*VDD, so these PINs and logic gates react to the signal earlier. If you want to see the moment when logic gates change their state, please add additional probes to the LUTs output. It will give you the ability to see tp timing.

Please, see the attached .gp3 files with my small corrections and the attached Simulation Results. 

Hope, it will help you to use the Simulation Tools 

Attachment: