Overview
IEC TR 63238-1:2019 - Process management for avionics - Electronics design - Part 1: Electrical signal properties, naming conventions and interface control document (ICD) - provides guidance and a template for creating Interface Control Documents (ICDs) for projects that connect electronic assemblies (for example, circuit card assemblies - CCAs - or electronic devices). It proposes electrical signal naming conventions, describes electrical interface content, and includes an informative example (Annex A) that demonstrates signal shapes and load/source descriptions to reduce integration and test errors.
Key topics
- ICD purpose and scope: Defines electrical properties and names for nets/pins of electronic assemblies to standardize interfaces and avoid misunderstandings during design, integration and test.
- Signal naming conventions: Offers recommended conventions and an example set of seven signal naming styles to make net-lists descriptive and machine-parsable.
- Electrical signal properties: Describes signal shapes (e.g., sinusoidal, rectangular, triangular variants) and classifies pins as sources (S) or loads (L), including examples of loads such as resistors, inductors and capacitors.
- ICD specification format: Standardized table header and parameter syntax:
- Param syntax types - L (list/drop‑down), F (floating point with SI prefixes), S (string/text).
- Units & defaults - default semantics and units handling when specifying parameters.
- Typical fields - description, connector type, reference designator, pin number, signal properties.
- Examples & diagrams: Figures and tables (Sig1–Sig6, Table A.1) illustrate how to document signal shapes and connector interfaces.
Applications and who should use it
- OEMs and avionics suppliers: Create and maintain ICDs for CCAs, modules and devices to ensure consistent electrical interfaces across suppliers.
- Systems and hardware engineers: Standardize signal naming and electrical property documentation to reduce design-integration mismatches.
- Integration and test teams: Use ICDs to define expected signal shapes, sources/loads and test conditions, reducing test complexity and rework.
- Configuration and procurement: Provide clear interface specs for contracts, parts selection and lifecycle management.
Practical benefits
- Reduces ambiguity in net-lists and connector pin definitions.
- Prevents avoidable design and integration errors and simplifies test planning.
- Facilitates supplier interoperability, traceability and electronic assembly maintenance.
Related standards and resources
- IEC 63238 series (Process management for avionics - Electronics design)
- IEC TS 62239-2:2017 (reference for electronic assembly definitions)
- IEC Electropedia and ISO/IEC Directives for terminology and drafting guidance
Keywords: IEC TR 63238-1, interface control document, ICD, signal naming conventions, electrical signal properties, avionics electronics design, CCA, OEM, electrical interface, net-list.