Wait we re no longer supposed to use open pdks

Question

Amro Tork · Answer

I think it s better to use volare

Luis Henrique Rodovalho · Answer

I use gf180 open pdks and it s so small I include some of its files magic rc and ngspice models only 1 8 MB in the git repository of my analog projects Simulation is straightforward this way If I knew how to install it automatically along with my git projects I would use it

Amro Tork · Answer

For simulation models please use Efabless version

Amro Tork · Answer

Luis Henrique Rodovalho · Answer

I know it is a noob question but is there a way to link the models directly to my git repository so I don t need to upload them with my project files

Amro Tork · Answer

You could use git submodule add to add the above repo as a submodule to your project

Luis Henrique Rodovalho · Answer

Thanks

Amro Tork · Answer

Example code

Amro Tork · Answer

Amro Tork · Answer

Make sure to run submodule update to keep track of changes

Luis Henrique Rodovalho · Answer

By the way has anybody simulated gf180 resistors My simulations with their resistors aren t working

Amro Tork · Answer

We are responsible of the quality of the models with NGspice

Amro Tork · Answer

Could you please send me details

Amro Tork · Answer

Cc < Farag Elsayed>

Amro Tork · Answer

< Luis Henrique Rodovalho>

Luis Henrique Rodovalho · Answer

< Farag Elsayed>

Luis Henrique Rodovalho · Answer

It should be a 1k Ohm per square resistor but it is not

Amro Tork · Answer

It s 1 2K

Amro Tork · Answer

Amro Tork · Answer

Let me check the data from foundry

Amro Tork · Answer

< Luis Henrique Rodovalho> Usually resistors has about 20 around the typical value I understand that are running typical That s what I m trying if the foundry data shows 1 2K or 1K exactly

Luis Henrique Rodovalho · Answer

But the simulation shows a 173 Ohm instead of 1 2k

Amro Tork · Answer

< Luis Henrique Rodovalho> I simulated the netlist that you sent me And I just put the results in the sheet that I shared

Amro Tork · Answer

I made some minor updates here

Farag Elsayed · Answer

``` resistor testbench param + sw stat global = 0 + sw stat mismatch = 0 temp 27 vr vr vss 0 xr vr vss vss ppolyf u 1k r width=1u r length=1u m=1 control dc vr 0 1 10m plot i vr endc Vin top GND 1 0 XR1 top GND GND ppolyf u 1k r width=1 0u r length=1 0u m=1 temp 25 control op let ires= 1 vin branch let res=1 0 ires print res endc library calling include design ngspice lib sm141064 ngspice res typical GLOBAL GND end```

Farag Elsayed · Answer

It s 1 2k

Amro Tork · Answer

``` resistor testbench include home atork test globalfoundries pdk libs gf180mcu fd pr models ngspice design ngspice lib home atork test globalfoundries pdk libs gf180mcu fd pr models ngspice sm141064 ngspice res typical param + sw stat global = 0 + sw stat mismatch = 0 temp 27 vr rn vss 0 xr vss rn vss ppolyf u 1k r width=1u r length=1u control dc vr 0 1 10m wrdata dc i vr endc```

Luis Henrique Rodovalho · Answer

So does it need a GND global to work

Amro Tork · Answer

< Luis Henrique Rodovalho> BTW sheet resistance is variable against L and W Large L and W usually better results

Luis Henrique Rodovalho · Answer

Maybe my models are outdated

Amro Tork · Answer

< Luis Henrique Rodovalho> possibly please check the link that I shared and use the models that I shared above

Amro Tork · Answer

I keep it up to date

Farag Elsayed · Answer

It doesn t matter using ` GLOBAL GND` you could remove it

Amro Tork · Answer

< Luis Henrique Rodovalho> I used your netlist Check mine please

Amro Tork · Answer

< Luis Henrique Rodovalho> Originally there was an issue with the resistor models and we resolved that more than 8 months back But unfortunately Google didn t get the updates so far May be you are still using those wrong models

Amro Tork · Answer

< Luis Henrique Rodovalho> If you have any issues with GF180MCU models please don t hesitate to contact me

Amro Tork · Answer

FYI I m using ngspice 40 to simulate

Luis Henrique Rodovalho · Answer

I didn t see any magic technology files Do you plan to include them Is Klayout able to extract GF180 netlists

Amro Tork · Answer

I don t support magic But we support klayout Klayout is fully qualified on all devices both for DRC and LVS

Amro Tork · Answer

Yes you should be able to do that

Amro Tork · Answer

Even on a very large designs

Amro Tork · Answer

One sec

Amro Tork · Answer

Amro Tork · Answer

< Luis Henrique Rodovalho> Please use this version for Klayout LVS and DRC

Amro Tork · Answer

Everything in that repo has been reviewed very carefully

Luis Henrique Rodovalho · Answer

Solved It was my models They were outdated

Amro Tork · Answer

For Simulation models we are facing a few issues with few devices now but it s work in progress CV characteristics for MOS devices Diodes IV CV ngspice somehow doesn t seem to model breakdown correctly

Amro Tork · Answer

Please make sure to use keep updating your models from the repo above

Amro Tork · Answer

LVS and DRC are fully updated

Amro Tork · Answer

If you have any issues with models I would advise opening an issue on the repo that I shared Also if you have any issues in DRC LVS please don t hesitate to open an issue on the repo above

Tim Edwards · Answer

< Tom> This conversation kind of took off and left the question behind but volare is just a repository that contains a pre compiled version of the PDK built by open pdks That saves the trouble and considerable disk and memory overhead of compiling it yourself But it is the same thing Also volare is version controlled whereas open pdks will just build to the latest versions of everything unless you specify otherwise which is a manual process It is very much the same difference as between installing a software package and compiling the software from source

Tom · Answer

Understood < Tim Edwards> thanks for the explanation