spice2wireviz

Convert LTspice SPICE netlists to WireViz wiring diagrams.

What it does

spice2wireviz reads SPICE netlist files (.net, .cir, .sp) and LTspice schematics (.asc) and generates WireViz YAML that documents the physical wiring: connectors, test points, and inter-module cables.

Two operating modes:

• Single module -- External interface of one subcircuit (its connectors, test points, port interface)
• Inter-module -- How multiple subcircuits/boards connect to each other

Install

uv tool install spice2wireviz
# or
pip install spice2wireviz

For .asc file metadata extraction (optional):

pip install spice2wireviz[asc]

Usage

From netlist files

# Inter-module wiring (auto-detected from top-level X instances)
spice2wireviz top_level.net -o wiring.yml --render

# Single module external interface
spice2wireviz design.net -s amplifier_board -o amp.yml

# Only connectors and test points, no ground
spice2wireviz design.net --include-prefixes J,TP --no-ground

# Inspect before converting
spice2wireviz design.net --list-subcircuits
spice2wireviz design.net --list-components
spice2wireviz design.net --dry-run

From .asc schematics

LTspice .asc files are supported with tiered netlist resolution:

1. Companion netlist (automatic) -- If a .net, .cir, or .sp file exists alongside the .asc (same basename), it's used for full connectivity. LTspice generates these automatically when you run a simulation.
2. LTspice generation (opt-in) -- Pass --generate-netlist to invoke LTspice and produce a .net file.
3. Metadata only -- Without a netlist, only component refs/values are available. Diagram generation is blocked, but --list-components still works.

# .asc with companion .net in the same directory -- works like .net input
spice2wireviz schematic.asc -s amplifier_board -o amp.yml

# No companion .net -- invoke LTspice to generate one
spice2wireviz schematic.asc --generate-netlist -o wiring.yml

# Inspect component metadata (no .net required)
spice2wireviz schematic.asc --list-components

Filtering

Cherry-pick what appears in the diagram:

--include-prefixes J,TP     # Only these component types
--exclude-refs X3,J_DEBUG   # Hide specific references
--include-nets "SIG_*"      # Glob patterns for net names
--no-ground                 # Hide GND connections
--no-power                  # Hide VCC/VDD connections

Development

uv sync --extra dev --extra asc
uv run pytest
uv run ruff check src/ tests/

Repository

git.supported.systems/warehack.ing/spice2wireviz