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4.6 Change Control and Deviations

The "Golden Process" validated during qualification is the only approved way to manufacture the part. Any variation from this baseline—whether intentional (Change Request) or accidental (Deviation)—introduces unknown variables. ThisWe chapteroperate definesunder thea "No Surprises" policy: suppliers are strictly prohibited from changing the "4M" (Man, Machine, Material, Method) without prior written approvalapproval. fromUncontrolled Danniechange Supplieris Quality.the primary driver of catastrophic field failures.

Supplier Change Control (PCN)

A Process Change Notification (PCN) is the formal mechanismcontract modification for a supplierpermanent toprocess shift. It is not an "FYI" email; it is a request afor permanent modification to their process.validation.

  • Trigger Events (What Requires Approval?a PCN?)::

      • IF Material: Changingchanges resin(e.g., Resin grade, solderSolder paste type, or sub-tier source.source) -> THEN PCN Required.
      • IF Machine: Movingchanges molds(e.g., toNew amold, new press, replacing a reflow oven, or adding a newNew SMT line.line, Reflow oven replacement) -> THEN PCN Required.
      • IF Method: Changingchanges cure(e.g., Cure time/temp, alteringInspection thelogic, inspectionTest plan,software orupdate) modifying-> testTHEN software.PCN Required.
      • IF Location: changes (e.g., Moving production to a differentnew buildingbuilding) or-> facility.THEN PCN Required.

The Notification90-Day Window:Rule:

Suppliers must issue a PCN at least 90 days prior to the proposedplanned implementationimplementation. date.This allows time for:

  1. Risk Assessment: Updating the FMEA.
  2. ValidationValidation: Requirements:
    • RiskRunning Assessment: FMEA update showing thea new risk profile.
    • Capability Data: New Cpk study verifyingand process stability.
    • Validation:a 3-Lot Safe Launch (100% Inspection) results.
    .
  3. ApprovalApproval:: Requires SQEEngineering and EngineeringQuality sign-off. Silence is NOT approval.

Deviation and Concession Control

A Deviation is a temporary permission to ship product that does not meetviolate the specification.law. It is a "Get Out of Jail Free" card that expires. It is used to keep the line moving, not to lower the standard permanently.

Decision Logic:

  • TypesIF ofDefect Deviationis Safety/Regulatory -> THEN:
       Denied. No exceptions.
    1. Pre-ProductionIF: RequestDefect tois useFunctional -> THEN Conditional Approval (Requires 100% screening at Supplier expense).
    2. IF Defect is Cosmetic -> THEN Concession (Approved with Limit Samples and commercial discount).

Constraints:

  • Time/Quantity Bound: Every deviation must have a temporaryhard processstop (e.g., Soft"Max Tooling)500 duringunits" NPI.
  • Production:or Request"Expires to ship a lot with a known minor defect (e.g., cosmetic scratch) to avoid line-down.
  • Risk Evaluation Logic:
    • Critical/Safety: Never Approved01-Nov").
    • Functional: Approved only with 100% Screening and Engineering concurrence.
    • Cosmetic:Visual Approved with "Limit Sample" and commercial concession (discount).
  • Mandatory Constraints:
    • Quantity/Time Bound: The deviation must specify an exact Quantity (e.g., 500 units) or Expiration Date (e.g., 2 weeks).
    • TraceabilityFlag:: Every box shipped under deviation must be clearly labeled:labeled "DEVIATION #XXXX". in neon/bold text.
    • ExpiryExpiry:: Once the limit is reached, the permission isauto-revokes. automaticallyAny revoked. Unauthorizedfurther shipments beyondare this point will be rejected at the dock.
    rejected.

Unauthorized Changes (The "Silent Killer")

Changing a process without notifying Dannie is a breach of contract and trust.an act of negligence.

Examples of "Silent Changes":

  • Definition: Examples includeUsing "Regrinding"Regrind" plastic(recycled plastic) > 20% without approval, changingapproval.
  • Swapping a capacitor brand tofor a "cheaper equivalent,"equivalent" orwithout skippingtesting.
  • Skipping a cure cycle to speed up thethroughput.
line.

  • ConsequenceConsequences::

    • Immediate Business HoldHold:: Supplier isstatus placeddowngraded onto "Do Not Source" status.Source."
    • LiabilityLiability:: Supplier is liable for all100% of validation costs, field recalls, and scrap associated with the unauthorized change.scrap.
    • AuditAudit:: Mandatory on-site "For Cause" on-site audit to re-qualify the process.
    entire line.

    • Final Checklist

    Control ElementPoint

    StandardCritical Requirement

    RiskNon-Negotiable of FailureRule

    PCN Window

    90 Days PriorTimeline

    Unvalidated90 processDays shiftsprior to change.

    No "retroactive" PCNs.

    Sub-Tier Change

    Requires ApprovalLock

    UnknownChanges materialat riskssub-suppliers controlled.

    You own your supply chain.

    Deviation Scope

    Qty/TimeSpecific LimitedQty or Date.

    PermanentOpen-ended "temporary"deviations fixesare void.

    Labeling

    Visible on BoxTraceability

    PollutingDeviation stockLabel withon badBox.

    No partslabel = Reject at Dock.

    Silent Change

    Contract BreachValidation

    CatastrophicData fieldmust failureprove equivalence.

    "We think it's okay" is not data.


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