klayout-pex (iic-jku) errors

7 recurring problems engineers report in klayout-pex (iic-jku), ranked by impact.

#65 by errors trackedVerificationECAD

Recurring klayout-pex (iic-jku) errors, by impact

  1. 1A KLayout-PEX run succeeded while a device dropped out of the extracted netlist, because the PEX and LVS decks had drifted apart and unrecognized device shapes extracted as plain wiring.Verification · Agent failure · 1 report74
  2. 2Every defect in #211 section C finishes with exit 0 and gives a netlist that simulates to a plausible wrong number. What caught them was a set of independent checks run on the output after every extraction: every device terminal has to sit on its own net's resistor network, every net has to be one connected piece, no port can touch nothing, total capacitance per net pair has to match the tool's own summary, and device counts by class have to match the schematic.ECAD · Agent failure · 1 report74
  3. 3With kpex held at 0.3.12 and KLayout moved from 0.30.3 to 0.30.10, the extracted current mirror's header went from 'vref vss vcopy sky130_gnd' to 'sky130_gnd vcopy vref vss'. Same port set, every device card byte-identical, stable across runs. The reporter ruled out KLayout's SPICE writer by measurement before filing. Filed Aug 10, active again today.ECAD · Agent failure · 1 report74
  4. 4KPEX extraction turns subcell pin labels into ports the top cell keeps internal. Child cells carry pin labels for their own LVS, and extraction promotes them to top-level ports on ordinary hierarchical analog macros. Labels that are right at one level of the hierarchy produce a wrong netlist at the next.ECAD · Agent failure · 1 report66
  5. 5On IHP sg13g2, KPEX 2.5D errors out on PCell inductors and HBTs because the tech info does not model the inductor pin layer or emitter window and has no device mapping for inductors.Verification · Agent failure · 1 report66
  6. 6The klayout-pex check step exits 1 on BAG and xschem schematics because its SPICE reader does not understand parameters or expressions.Verification · Agent failure · 1 report66
  7. 7The kpex --check command on a sky130A netlist with units KLayout expects fails on correct devices and exits 1, while the same lines without units pass. Two tools in one flow read the same SPICE line at different scales: schematic MOSFET sizes in microns, KLayout in metres.ECAD · Agent failure · 1 report66

How it fails

  1. Agent failure7

Engineering tools that address these errors

Sourced from public community reports. Costs and delays on individual entries are modeled estimates, not measurements.