kicad-schematic-design

KiCad Schematic Design

Use this skill for every KiCad schematic task in the active workspace. Treat the schematic as an electrical contract, a manufacturing input, and a document that another engineer can read without guessing.

Operating Modes

Choose the mode from the latest user request.

• Create or edit: inspect the project, define requirements, make the requested changes, validate, and show the changed-file diff.
• Review or diagnose: perform read-only inspection and validation. Do not edit the schematic, project, PCB, reports, or settings.
• Open or inspect: open KiCad and inspect the visible state. Do not infer permission to edit from an open request.

Respect workspace instructions and preserve user changes. Do not overwrite an existing project until the requested target is explicit.

Design Contract Before Drawing

Collect or state assumptions for:

• Circuit function, signal direction, operating modes, and failure behavior.
• Every external net: source, sink, connector or port, voltage or logic level, and expected current or frequency.
• Power rails: minimum, nominal, and maximum voltage; continuous and peak current; startup and shutdown behavior.
• Environment, temperature, mechanical constraints, EMC constraints, and board manufacturing limits.
• Component MPN, datasheet, tolerance, voltage rating, package, lifecycle, and approved alternatives.

Create an endpoint ledger before placing symbols. Each external net must have a visible source and destination, or an explicit hierarchical or global port. A rail label alone does not define where power enters the circuit. For a board-level circuit, expose required inputs, outputs, grounds, buses, test points, and measurement nodes with connectors or ports.

When a requirement is unknown, record the assumption and mark the affected claim unverified. Do not silently invent load current, connector pinout, operating temperature, or external source behavior.

Project and Library Rules

1. Inspect .kicad_pro, .kicad_sch, .kicad_pcb, sym-lib-table, and fp-lib-table before placement.
2. Use installed KiCad symbol and footprint libraries through the KiCad GUI, local KiCad MCP, or a library parser. Record every exact lib_id and footprint identifier.
3. Resolve inherited symbols through their declared parent definition. Preserve all pins, graphics, electrical types, UUIDs, and instance records.
4. Compare critical IC, connector, protection, sensor, and power-device pin maps with the manufacturer datasheet. Library consistency alone does not establish physical correctness.
5. Assign complete library footprint identifiers. Reject malformed or concatenated library and footprint names.
6. Use one authoritative reference per component. Annotate after placement and recheck duplicate references.
7. Use real MPNs for fabrication designs. Keep generic symbols only when the user accepts a conceptual schematic.