https://open-source-silicon.dev logo
#sky130
Title
# sky130
v

Vikas Sachdeva

03/21/2022, 9:46 AM
Hi. I am trying to create labs on cdc using skye130 libs. Is there a synchronizer cell in the libs? Also any work has been done characterising and identifying parameters like Tau for MTBF calculations?
k

Kauser Johar

03/21/2022, 9:49 AM
I tried looking for synchronizer cells in the library but failed to find them. We need to use sync cells in the design for CDC. Let me know please if you find something before me!
v

Vikas Sachdeva

03/21/2022, 11:55 AM
Hi @User We are in the same boat. Did you find any workaround?
k

Kauser Johar

03/21/2022, 11:55 AM
My workaround is to use a behavioral model of a 2stage sync cell and then rely on Yosys to synthesize it.
Ideally you want to the two flops to sit close to each other which cannot be guaranteed, but I'm assuming this should be okay if you aren't intending to run at really high frequencies.
v

Vikas Sachdeva

03/21/2022, 12:59 PM
It should be ok if they are placed together. But MTBF needs to be calculated
k

Kauser Johar

03/21/2022, 1:06 PM
It should be ok if they are placed together. But MTBF needs to be calculated
Perhaps you could experiment with the sky130 library and calculate MTBF and publish it for a wide range of frequencies?