After a lot of procrastination, I'm at least gonna try a bias generator. What does it take to throw my hat into https://docs.google.com/spreadsheets/d/1Zx24qZ0sjKtLi2l32qYPZbZev3IYUEeaR30hk7oCfbw/edit#gid=0 ? And where would I find the skywater process variation data for anything that could be used as ohmic resistor?? Is deadline 01 March 2024 08:00Z or 02 March 2024 08:00Z?

(1) On the spreadsheet, just leave a comment in the same row as the IP block you're choosing. Write "1" in the comment if it's your first (or only) choice for a submission ("2" if it's a second choice, etc.). (2) Deadline is 02 March 2024 12:00 PST (or 01 March 2024 115959 PST, if you like). (3) Process variation data is buried in the models according to the multiplier for the gaussian in expressions containing

MC_PR_SWITCH

.

The spreadsheet tells me that I can only comment, not edit. Feature or bug?

Yes, you can only comment. I periodically check the spreadsheet and convert comments into colored blocks.

ok, #worksforme

The high resistance poly resistor model is here: https://github.com/google/skywater-pdk-libs-sky130_fd_pr/blob/f62031a1be9aefe902d6[…]7627436/cells/res_high_po/sky130_fd_pr__res_high_po.model.spice It has a sheet resistance of 2000 ohm, and a variability of 15% https://github.com/google/skywater-pdk-libs-sky130_fd_pr/blob/f62031a1be9aefe902d6d54cddd6f59b57627436/models/r%2Bc/res_high__cap_high__lin.spice

Thanks! That helps. As I have procrastinated too long for the last week and a half to get them done before the deadline, do ready-to-use characterization circuits similar to https://github.com/tatzelbrumm/sky130_TAC3/blob/tatzelbranch/playground/nfet_03v3_gmtest.sch exist for other skywater 130 components? (see README of https://github.com/tatzelbrumm/sky130_TAC3/tree/tatzelbranch, playground::nfet_03v3_gmtest for the general idea)

Stefan Schippers has put a lot of good example testbench circuits into the xschem library for sky130. If you start xschem using the

xschemrc

file in the sky130 PDK but without specifying any schematic filename on the command line, it will bring up a wonderful page featuring all the testbenches and instructions on how to run them.

Like with every "community" project, there's the stackoverflow problem: For every one correct answer, there are 10 wrong answers, and worse yet, 3 almost correct answers. Can you give the link to "the xschem library for sky130"? EDIT: Do you mean https://github.com/StefanSchippers/xschem_sky130/blob/main/xschemrc pointing to https://github.com/StefanSchippers/xschem_sky130/blob/main/sky130_tests/top.sch ?

Yes, that's exactly the one. If you install the sky130A PDK with open_pdks or volare, it will be installed in

$PDK_ROOT/sky130A/libs.tech/xschem/

; by copying

$PDK_ROOT/sky130A/libs.tech/xschem/xschemrc

to your working directory (or pointing to it from an xschem command line option), running

xschem

without a schematic filename on the command line will automatically start with the contents of

sky130_tests

.