Design History File (DHF) Workbench¶
The MEMO DHF Workbench provides a centralized, model-driven environment for generating and managing regulated documentation for medical device development.
Terminology note: "DHF" comes from the FDA's legacy Quality System Regulation (21 CFR 820.30(j)). FDA's QMSR (Quality Management System Regulation, effective February 2026) replaces most of Part 820 by incorporating ISO 13485:2016 by reference, and ISO 13485 §7.3.10 calls the equivalent record the "design and development file" rather than "DHF." MEMO keeps "DHF" as the primary term throughout the UI and codebase because it remains the term practitioners and eQMS tooling use day to day — but be aware the current regulation text itself says "design and development file."
The DHF Dashboard showing completeness metrics across 18 document types.
Core Concepts¶
In MEMO, a document is not a static file but a specialized View into the semantic model. As your SysML model evolves, your documents update automatically.
1. The 18 DHF Document Types¶
MEMO includes built-in templates for the 18 essential documents required by ISO 13485, ISO 14971, and IEC 62304.
| Group | Key Documents | Standards |
|---|---|---|
| Risk | RMP, Hazard Analysis (HAR), FMEA, FTA | ISO 14971 |
| Design | System Arch (SAD), Software Design (SDS), SOUP List | IEC 62304, ISO 13485 |
| Traceability | Requirements Traceability Matrix (RTM) | ISO 13485 |
| Compliance | Software Dev Plan (SDP), Usability (UER), Cybersecurity | IEC 62366, IEC 81001-5-1 |
2. Snapshots & Change Tracking¶
Regulatory standards require you to maintain a history of changes. - Snapshot: Captures the current state of a document as a baseline. - Diff: Compares your current model against a previous snapshot to show additions, deletions, and modifications. - Redlining: Automatically generates a "tracked changes" version of a document (HTML or DOCX).
Workflow¶
Documents and templates¶
The DHF explorer lists only documents that currently exist in the project
under dhf/documents/. Methodology bindings and template definitions do not
appear as documents.
Use + New Document to create a document from a built-in meMO template, a
reusable project template, or a blank page. Project templates live separately
under dhf/templates/. Choose Add new template in the creation wizard to
save a reusable Markdown template there and create the first document from it.
Templates remain reusable and can create more than one document.
Reviewing Status¶
Open the DHF Dashboard from the top toolbar to see the status of your entire file. - Complete: All required sections have been populated with model data. - Partial: Some required sections are empty or have validation errors. - Empty: No model data has been allocated to this document type yet.
Generating Documents¶
You can generate documents individually or as a "Review Packet."
Using the UI: 1. Click a document card in the DHF Dashboard. 2. Review the live preview. 3. Click Export and choose your format (HTML, DOCX, or PDF).
Using the CLI:
# Export the Risk Management Plan to Word
memo export dhf --target rmp --format docx
# Generate a full review packet for a design review
memo dhf review-packet --output ./v1-baseline
Configuration¶
Control which documents are enabled and what standards they target in your memo.dhf.yaml file: