{"sections":[{"heading":"Check the definition","steps":["Write the directive as .MODEL, with no space between the dot and MODEL. A malformed . MODEL line was responsible for an older support report.","Check that the model name on the junction instance exactly matches the defined name.","Verify the documented model type and name=value pairs, parentheses and unique component names.","Read the parser/run diagnostic before comparing the waveform."]},{"code":".MODEL JJMOD JJ(RN=10 CAP=2.5p IC=1m)\nB1 1 2 JJMOD area=1.2","heading":"Generic example"},{"heading":"Verify the intended model","paragraphs":["Use a small circuit with known bias and output requests. Older parser behaviour must not be treated as proof of current fallback semantics; require an explicit valid definition."]}],"canonical_url":"https://www.sun-magnetics.com/knowledge-base/josim-model-syntax","url":"/knowledge-base/josim-model-syntax","known_issues":[],"search_record":{"execution":true,"relatedProducts":[],"version_tags":["JoSIM-Pro 2.9 target"],"text":"A junction model is missing or behaves like the wrong model Check .MODEL spelling, model names and parameters before changing device physics or simulation settings. JoSIM-Pro 2.9.0 release target; review-build/source evidence Troubleshooting Check the definition Write the directive as .MODEL, with no space between the dot and MODEL. A malformed . MODEL line was responsible for an older support report. Check that the model name on the junction instance exactly matches the defined name. Verify the documented model type and name=value pairs, parentheses and unique component names. Read the parser/run diagnostic before comparing the waveform.  Generic example .MODEL JJMOD JJ(RN=10 CAP=2.5p IC=1m)\nB1 1 2 JJMOD area=1.2 Verify the intended model Use a small circuit with known bias and output requests. Older parser behaviour must not be treated as proof of current fallback semantics; require an explicit valid definition. ","id":"josim-model-syntax","keywords":"","kind":"Troubleshooting","title":"A junction model is missing or behaves like the wrong model","product":"JoSIM-Pro"},"version":"2.9.0 release target; review-build/source evidence","id":"josim-model-syntax","related":["/knowledge-base/josim-junction-resistance","/knowledge-base/josim-singular-circuit"],"downloads":[],"publication_status":"published","numerical_output":null,"provenance":{"execution_checks":[{"scope":"CLI valid-model control and spaced-directive rejection","result":"passed","articles":["josim-model-syntax"],"version":"Installed JoSIM-Pro 2.9.0 Windows","id":"VAL-008","records":["troubleshoot-model-valid","troubleshoot-model-spaced-directive"],"limit":"One generic circuit, not all model families."}],"figure_evidence":[],"review_notes":["Support history informed this draft. Current-source guidance has been checked; a fresh walkthrough on the intended distributed release and product-owner review remain pending."],"scope":"Recorded inputs/builds only. Complete walkthrough and final-package acceptance remain separate.","verification_requirements":{"gui_method":"not-required-for-this-answer","status":"review-incomplete","illustrations":"not-required-for-this-answer","required":["technical-review","release-applicability","execution","recovery"],"legacy_walkthrough_field":"pending retained; not evidence of a complete scenario"},"sources":[{"id":"support:SUP-012","section":"Generalised editorial finding; outcome qualification retained"},{"id":"josim-pro:docs/manual_source/sections/troubleshooting.tex","section":"Netlist syntax, component definitions, and model lines"},{"id":"josim-pro:docs/manual_source/sections/syntax.tex","section":"Josephson junction and model definitions"},{"id":"validation:windows-cli-20261102","section":"VAL-008; scope and limits recorded"},{"id":"owner:technical-review-20261102","section":"JoSIM-Pro 2.9 chosen as the public starting path; release availability must be checked before publication"}]},"title":"A junction model is missing or behaves like the wrong model","type":"Troubleshooting","markdown_url":"/_functions/kbResource?path=markdown%2Fjosim-model-syntax.md","summary":"Check .MODEL spelling, model names and parameters before changing device physics or simulation settings.","product":"JoSIM-Pro"}