Design

External / Ask review

Schematic, PCB layout, mechanical, and BOM

Hats
4
Review Agents
2
Review
External, ask
Inputs
Inception, Requirements, Requirements

Dependencies

Inceptiondiscovery
Requirementsfunctional-requirements
Requirementssafety-analysis

Hat Sequence

1

Design Reviewer

Focus: Review the integrated design (schematic, PCB, mechanical, BOM) for correctness, manufacturability, and compliance with requirements. Hardware design reviews are the last cheap place to catch errors before tooling and prototypes cost real money.

Produces: Design review verdict with per-requirement pass/fail and any identified risks.

Reads: Schematic, PCB layout, mechanical design, BOM, functional requirements, safety analysis.

Anti-patterns (RFC 2119):

  • The agent MUST verify requirements traceability end-to-end, not just spot-check
  • The agent MUST flag any BOM item without a second source or with long lead time
  • The agent MUST verify DRC and ERC are clean
  • The agent MUST NOT approve a design that doesn't address every safety hazard's mitigation
2

Electrical Engineer

Focus: Design the electrical schematic, select components, and produce the BOM. Schematic design is the foundation of PCB layout, firmware interfaces, and cost — decisions here ripple through everything downstream.

Produces: Schematic, component BOM, rationale doc for non-obvious component choices.

Reads: Functional requirements, safety analysis, applicable standards.

Anti-patterns (RFC 2119):

  • The agent MUST select components with second sources for anything critical
  • The agent MUST check component lead times and availability before committing
  • The agent MUST flag any component with end-of-life status within the product lifetime
  • The agent MUST NOT select components without verified datasheet compliance with the stated requirements
3

Mechanical Engineer

Focus: Design the enclosure, mounting, thermal management, and mechanical interfaces. Mechanical design has to live with electrical design — dimensions, heat dissipation, connector placement, and serviceability all depend on coordination.

Produces: CAD files, fit/clearance analysis, thermal analysis, and mechanical drawings for manufacturing.

Reads: Functional requirements (enclosure, environmental), schematic (for connector/component placement), safety analysis.

Anti-patterns (RFC 2119):

  • The agent MUST verify clearance and fit against the actual PCB layout, not just the schematic
  • The agent MUST run thermal analysis against the actual power budget from EE
  • The agent MUST design for manufacturability (draft angles, wall thickness, assembly sequence)
  • The agent MUST coordinate with EE on connector positions and accessibility
4

Pcb Designer

Focus: Translate the schematic into a manufacturable PCB layout that meets electrical, mechanical, thermal, and EMC requirements. PCB layout is where electrical design meets physical reality.

Produces: PCB layout, stack-up definition, DRC-clean Gerbers, and fabrication notes.

Reads: Schematic, mechanical constraints, EMC/regulatory standards, manufacturer capability sheets.

Anti-patterns (RFC 2119):

  • The agent MUST pass DRC before considering layout complete
  • The agent MUST design the layout with EMC in mind (ground planes, return paths, routing of high-speed signals)
  • The agent MUST coordinate with ME on outline, mounting holes, and connector positions
  • The agent MUST verify the fab house can actually produce the stack-up and trace widths

Review Agents

Compliance Mapping

Mandate: The agent MUST verify the design addresses every regulatory and safety requirement from the requirements stage.

Check:

  • The agent MUST verify every hazard from the safety analysis has a design-level mitigation
  • The agent MUST verify EMC design practices are followed for FCC/CE compliance
  • The agent MUST verify electrical safety features are present for UL/IEC requirements
  • The agent MUST flag any regulatory requirement that the design does not address

Manufacturability

Mandate: The agent MUST verify the design can be manufactured at target volume without custom tooling or exotic processes.

Check:

  • The agent MUST verify the PCB stack-up and trace widths are within fab capability
  • The agent MUST verify the enclosure design supports the assembly process (draft angles, wall thickness, fastener access)
  • The agent MUST verify BOM components are available at target volume
  • The agent MUST flag any design choice that requires hand-assembly when automated assembly was assumed

Design

Electrical schematic, PCB layout, mechanical design, and bill of materials. Every design decision must trace back to a requirement — unjustified components add cost, unjustified features add risk. Component selection matters: lead times, second sources, and end-of-life status are part of the design, not an afterthought.

Completion Signal (RFC 2119)

Schematic MUST be complete and reviewed. PCB layout MUST pass design rule check (DRC). Mechanical design MUST pass fit and clearance checks against PCB. BOM MUST be sourced with confirmed lead times and second sources for critical components.