1.5 Release Checklist and Freeze Rules

For the EMS provider, the NPI (New Product Introduction) Data Intake Gate is an important liability shield. Once you formally accept a data pack and release the Traveler to the manufacturing floor, you functionally take ownership of the outcome. If the input data is ambiguous and you proceed on assumptions, the resulting scrap is your financial loss.

You must utilize this intake gate to enforce a clear “Stop/Go” policy. Do not allow a project to pass into Procurement or CAM processing until the Golden Data Pack (GDP) is validated as a locked, cohesive entity.

The Mechanics of the Freeze: Integrity Checks

Your first operational duty is to verify the customer has actually stopped changing the design. Receiving an archive named Draft_v3_Final.zip is a red flag.

1. The Checksum Validation

Upon receiving the GDP archive over the network, verify its integrity.

• Action: Run a SHA-256 (or MD5) hash check on the downloaded ZIP file.
• Review: When the computed hash diverges from the customer’s stated hash in the PO or release email, the file must be rejected. The file is corrupted or was intercepted during transit.

2. The Timestamp Audit

Extract the archive and audit the “Date Modified” timestamps of the internal files.

• The Red Flag: If the Gerber files are timestamped Monday, but the BOM is timestamped Wednesday, the package is out of sync.
• Review: When the timestamps show significant variance (e.g., >48 hours divergence between schematic BOM generation and CAD output generation), place the data pack on hold. Request that the customer explicitly certify in writing that the newly generated BOM perfectly matches the older board revision.

3. The Ban on “Email Patches”

Avoid accepting “patch” updates via email threads (e.g., “Hey, please use this updated pick-and-place file instead of the one in the zip”).

• The Rule: The GDP is an atomic entity.
• Action: When the customer emails an updated file, demand a completely new GDP Revision (e.g., Rev A ⭢ Rev B). Do not manually overwrite files in your local CAM directory, as that destroys system traceability.

The Intake Checklist: Acceptance Criteria

Before data touches your ERP or CAM tools, it must pass the Initial Review. This checklist prevents wasting engineering hours processing invalid data.

The Category	The Inspection Step	The Go/No-Go Metric
The Manifest	Verify presence of README or Manifest file.	File exists and lists exact EDA Tool Versions.
Sync Check	Cross-check Revision string in BOM vs. Gerbers vs. Drawings.	All Revisions perfectly match (e.g., all are “Rev 05”).
Completeness	Verify the critical file triad exists.	Netlist, Solder Paste Layer, and Centroid XY data are all present.
Machine Readability	Open BOM and XY files in a raw text editor.	Text is cleanly delimited; zero binary garbage characters.
BOM Status	Grep the MPN column for “TBD” or “Contact Engineering”.	0% “To Be Determined” entries allowed.
Authorization	Check for “Released” watermarks or PLM status.	Zero “DRAFT” or “PRELIMINARY” watermarks on drawings.

Stop-Build Triggers

Define triggers that obligate your team to stop the intake process and return the data pack to the customer. It is far more efficient to delay a launch by 24 hours than to procure $50,000 of incorrect components.

Trigger 1: The Mixed-Revision Pack

• Observation: The Pick-and-Place file contains RefDes locators (e.g., U50, C12) that physically do not exist in the BOM.
• Action: Reject. The assembly instructions command the machine to place parts that the procurement instructions did not buy.

Trigger 2: The Silent Specification

• Observation: The Fab Drawing demands “Impedance Controlled,” but absolutely no stackup table or target values are provided.
• Action: Hold for Engineering Query (EQ). Do not allow your CAM engineer to guess the dielectric thickness.

Trigger 3: The Unsigned Traveler

• Observation: The customer demands a “Quick Turn” build but has not formally approved the GDP in their PLM or tied it to a Purchase Order.
• Action: Hold. Without formal approval, “Golden” data is just a suggestion.

Engineering Rule: If you are required by management to proceed with a “Conditional Release” (e.g., to order long-lead-time silicon while the bare board design is still finalizing), create a specific “Risk Buy Waiver” form that the customer must sign. Isolate the risk entirely to procurement; do not start hard tooling.

Final Baseline Checklist

The Control Point	The Operational Requirement	The Go/No-Go Metric
Intake Hash	Checksum verified against sender’s data.	Matches perfectly (Green Light).
File Architecture	Standard 00-05 folder structure.	Zero “misc” or “old_versions” folders exist.
Revision Sync	BOM/CAD/Drawing revisions align.	100% string match across all headers.
Constraint Check	Fab Drawing notes reviewed.	Materials and tolerances are physically achievable in your factory.
Authorization	The PO references the exact GDP filename.	The formal link is established.