7.2 Glossary of Terms & Acronyms

Term

Meaning (plain and quick)

See also →

A-610 (IPC-A-610)

Visual acceptability standard for electronic assemblies (your day-to-day “is this OK?” book).

J-STD-001, 7711/7721, Class

ACL (Airflow/Current Limit)

In burn-in, guard bands for fan speed or current so trends don’t drift into failure.

Burn-in, Guard band

AQL

“Acceptable Quality Level.” Sampling intensity for incoming or in-process inspection.

Sampling plan, SQE

AOI

Automated Optical Inspection of solder/placement using cameras and rules/ML.

SPI, AXI

AXI

Automated X-ray Inspection (2D/3D/laminography) for hidden joints (BGA/QFN).

AOI, BGA

AVL

Approved Vendor List for parts/materials you’re allowed to buy.

SCAR, PPAP, Procurement

BGA

Ball Grid Array package with hidden solder balls under the part.

AXI, Head-in-pillow

BIB (Burn-in Board)

Fixture that lets multiple units run in a chamber during burn-in.

Burn-in, Rack

BOM

Bill of Materials—what goes into the product (PN, qty, AVL).

MBOM, Kitting

Boundary Scan (BSCAN/JTAG)

Test method using scan chains to toggle/observe pins and program devices.

ICT, DFT

Bow/warp

PCB flatness errors that cause placement/reflow and fit issues.

Panelization, Standoffs

CAPA

Corrective/Preventive Action—formal fix to stop recurrence.

SCAR, ECN, Root cause

CoC / CoA

Certificate of Conformance / Analysis from supplier proving spec compliance.

Incoming, SQE

Class (1/2/3)

IPC workmanship class; most EMS ships Class 2; Class 3 is high-reliability.

A-610, J-STD-001

CMC / Cpk / Cp

Capability metrics; how tight and centered a process runs vs spec.

SPC, Ppk, Window

Conformal coat (CC-830)

Protective coating over assemblies; keep out of connectors/keepouts.

Masking, Potting

CPA / TPA

Connector Position Assurance / Terminal Position Assurance—plastic locks that ensure full mate.

Mating sequence, Tug test

CTE

Coefficient of Thermal Expansion—mismatch drives solder/mechanical stress.

Warpage, Reliability

CTQ

Critical-to-Quality requirement you must control/measure.

Control plan, FMEA

DFM / DFA / DFT / DFx

Design for Manufacturability/Assembly/Test—rules that raise yield and coverage.

3.1, Golden pack

DPMO / PPM

Defects per Million Opportunities / Parts Per Million—defect metrics.

Yield, COPQ

DOE

Design of Experiments—structured tests to find best process window.

Window finding, SPC

ECN / ECO

Engineering Change Notice/Order—controlled design or doc changes.

Revision, Golden unit

EMC / EMI

Electromagnetic Compatibility / Interference—keep noise in/out via grounding/shields.

Shield clamp, Bond <0.1 Ω

ENIG / OSP / ImmAg / ImmSn / HASL

PCB finishes; affect solderability and shelf life.

Finish, J-STD-003

EOL / EOO

End-of-Life / End-of-Order—lifecycle or last-time buy status.

AVL, Procurement

E-stop

Emergency stop button on equipment/fixtures; must be reachable.

Hipot cage, Interlock

ERP

Enterprise Resource Planning—materials, POs, inventory; pairs with MES.

MES, Kitting

ESD (S20.20)

Electrostatic Discharge control program—zones, straps, floors, audits.

Shielding bag, Pink bag

F/G Terminals (Ring/Fork)

Lugged terminations to studs; often earth (PE) points.

Torque, <0.1 Ω

FA / FAI

First Article (Inspection)—first units built with deep checks; forms the reference.

Golden unit, 27.3

FCT

Functional Test—power, signals, performance checks.

ICT, Burn-in

Fiducial

Registration marks for machines (pick-and-place, AOI, stencil).

Global/local fiducials

FIFO

First-In, First-Out—inventory handling to control age/shelf life.

MSL, Shelf life

FIPG

Formed-in-Place Gasket (dispensed bead) for seals.

Gasket, Compression %

FPY

First Pass Yield—percent passing a step the first time.

Pareto, Rework

FR-4 / Tg

PCB laminate and its glass transition temperature; impacts warpage.

Stackup, Reflow profile

Gage R&R

Measures measurement system variation (Repeatability & Reproducibility).

MSA, SPC

Golden board/unit

Known-good reference sample used for teaching and debug.

FAI pack, Libraries

GS1 / QR / DataMatrix

Barcode standards; 2D codes for SN/MAC/etc.

Label map, Verifier grade

Head-in-pillow

BGA defect: ball and paste don’t fuse; looks “kissed” in X-ray.

Voids, Profile

Hermes / SMEMA

Line-handshake standards for board transfer/connectivity.

Buffers, Line control

Hipot / IR

Dielectric withstand high-voltage test / Insulation resistance.

Safety test, Leakage

Hot lot

Priority lot that jumps the queue (customer or containment driven).

Containment, Quarantine

ICT

In-Circuit Test via bed-of-nails; measures nets/components quickly.

Boundary Scan, Fixture

IMDS / RoHS / REACH

Material declarations/regulatory constraints.

Regulatory labels, Compliance

IPC-2581 / ODB++ / Gerber

PCB manufacturing data formats.

Centroid, CAM

IP (Ingress Protection)

Dust/water rating (e.g., IP65, IP67); requires sealing proof.

Gasket, Compression %

J-STD-001/002/003/033/020

Solder process; component/PCB solderability; moisture handling and reflow classification.

A-610, MSL

Kanban

Pull-based replenishment signal (cards/bins).

Supermarket, WIP

Kitting

Pulling the right parts per work order/variant; accuracy drives yield.

AVL, Shortage

Land pattern (IPC-7351)

Footprint geometry for parts on the PCB.

Aperture, Courtyard

Lean / 5S / Visual Mgmt

Organize to see problems: Sort, Set, Shine, Standardize, Sustain.

Andon, Shadow board

Lot

Group of items produced together under common conditions.

Traceability, IPC-1782

MBOM / EBOM

Manufacturing BOM (what you build with) / Engineering BOM (what is designed).

BOM, PLM

MBB / HIC

Moisture Barrier Bag / Humidity Indicator Card for MSL parts.

MSL, Dry cabinet

MES

Manufacturing Execution System—routes, WIP states, work records tied to SN.

ERP, Traceability

MOQ

Minimum Order Quantity from a supplier.

Procurement, AVL

MOV / Y-cap

Surge protector / EMI capacitor to earth; affect Hipot/leakage.

Safety test, Trip

MSA

Measurement System Analysis—ensures your gauges are trustworthy.

Gage R&R, SPC

MSL

Moisture Sensitivity Level for ICs; drives floor-life and baking.

J-STD-033, Bake

NCR

Non-Conformance Report ticket; records defect outside spec.

MRB, Disposition

NIST traceable

Calibration linked to national standards.

Calibration, Certificate

NPI

New Product Introduction—prototype to pilot to volume transition.

FAI, Golden

NPTH / PTH

Non-Plated / Plated Through Holes.

Via-in-pad, Drill

Nylock / Prevailing-torque

Nuts with built-in friction to resist loosening.

Threadlocker, Torque

OEE

Overall Equipment Effectiveness: Availability × Performance × Quality.

SMED, Bottleneck

ODB++

Rich PCB data format; alternative to Gerber.

IPC-2581

OLP / OPL

One-Point Lesson (single-page standard/learning with photo).

Knowledge base, CAPA

Open time (paste)

Time solder paste remains printable after exposure.

Stencil, SPI

OSP

Organic Solderability Preservative finish on PCBs.

ENIG, HASL

OTP / eFuses

One-Time-Programmable bits; enable secure boot/locks.

Provisioning, 25.3

Pareto

Bar chart ranking defect types by frequency or cost.

27.1, Root cause

PE (Protective Earth)

Safety ground; must bond to accessible metal <0.1 Ω.

Hipot, Earth bond

Pigtail (shield)

Short drain wire from shield; keep ≤10 mm when 360° clamp isn’t possible.

Shield clamp, EMC

PLM

Product Lifecycle Management—source of drawings/CAD/specs.

ECN, MBOM/EBOM

PnP (Pick-and-Place)

SMT placement machine.

Feeders, Fiducials

Poka-yoke

Mistake-proofing (keys, guides, software interlocks).

CPA/TPA, Fixtures

PPAP

Production Part Approval Process—supplier qualification package.

FAIR, SCAR

Ppk / Pp

Long-term capability indices (include shifts); cousins of Cpk/Cp.

SPC, Run chart

PPM

Parts Per Million (defects); see DPMO when counting opportunities.

Yield

Press-fit

Pin insertion into plated holes without solder; force-displacement monitored.

7711/7721, Acceptance

PSA

Pressure-Sensitive Adhesive for labels/gaskets.

Label map, Dwell

PTH

Plated Through Hole—barrel has copper; used for THT and vias.

THT, Via

Quarantine (NG-QUAR)

Physical/data state to isolate failed units/lots.

Containment, MRB

QBR

Quarterly Business Review with supplier or design.

Scorecard, SCAR

QFN / QFP / SOT / LGA

Common SMT packages with different lead styles.

Land pattern, Reflow

R&R (Rework & Repair)

Fixing defects to bring within spec (7711/7721 methods).

Rework ticket, Traveler

RMA

Return Material Authorization—customer return process.

COPQ, Traceability

ROSE / SIR

Ionic cleanliness tests (residue level / insulation resistance over time).

Cleaning, J-STD-001

RoHS / WEEE

EU environmental directives: hazardous substances / end-of-life recycling.

Regulatory labels, IMDS

Root cause

The changeable reason a failure happened (Design/Supplier/Process).

27.2, CAPA

SCAR

Supplier Corrective Action Request—formal ticket to supplier with proof and containment.

SQE, PPAP

Shielding bag (metal-in)

ESD bag that forms a Faraday cage—not the pink bag.

ESD, Pink bag

Shortage

Missing parts vs kit; drives substitutions or holds.

Kitting, AVL

Shrink (label)

Heat applied to seat labels/gaskets per spec.

Dwell, Roller

SIR

Surface Insulation Resistance test (post-cleanliness reliability).

ROSE, CC-830

SKU / Variant

Specific sellable configuration; drives labels, tests, firmware.

MES, Recipe

SMED

Single-Minute Exchange of Die—methods to slash changeover time.

5S, OEE

SMT / THT

Surface-Mount / Through-Hole Technology assembly processes.

Reflow, Wave, Selective

Solderability (J-STD-002/003)

Ability of plating (parts/PCBs) to wet with solder.

Finish, Flux

SPI

Solder Paste Inspection—3D volume/area/height before placement.

AOI, Print window

SPC

Statistical Process Control—charts/limits to detect drift (Cp/Cpk, Ppk).

Window, Run chart

SQE

Supplier Quality Engineer—owns SCARs, audits, incoming plans.

Supplier, PPAP

Stencil (step/nano)

Metal foil that prints paste; step areas tune volume.

Aperture, Aspect ratio

Supermarket (line-side)

Small, controlled inventory near the cell to avoid starvation.

Kanban, Kitting

SWI

Standard Work Instruction (photos + callouts) at the station.

OPL, Golden pack

Takt

Beat of production (available time / demand).

Line balance, Bottleneck

TAL

Time Above Liquidus—portion of reflow profile when solder is liquid.

Profile, Voids

Tape & reel / Tray / Stick

Component packaging styles for SMT.

Leader, Feeder

TAR (Test Accuracy Ratio)

Reference accuracy vs DUT tolerance (target ≥4:1).

Calibration, MSA

TC / ΔT

Thermocouple / temperature rise over ambient.

Profile, Burn-in

TE / PE / QE / ME

Test / Process / Quality / Manufacturing Engineer roles.

Roles & handoffs

Thermal pad (TIM)

Interface material (pad/grease/PCM) between hot part and sink.

Compression %, Cross-torque

Threadlocker

Anaerobic resin to lock screws (blue/purple/red grades).

Torque, Prevailing-torque

TIM

Thermal Interface Material—pads, paste, phase-change.

Heat sink, Compression

Tombstone

2-pin chip stands up during reflow (one end lifts).

Aperture, Placement

Torque map

Posted table of torque setpoints (and condition: dry/oiled/243).

Residual torque, Verification

Traceability (IPC-1782

)

Lot → unit genealogy depth; labels/DB links in MES.

Serialization, 2D code

Traveler

Packet/record that moves with the unit through operations.

MES, Route

UUT / DUT

Unit/Device Under Test—what the fixture is exercising.

FCT, ICT

Vac decay / Pressure decay

Leak test methods for IP enclosures.

IP rating, Seal

Via-in-pad

Plated via placed in a pad; good routing, tricky assembly.

Fill/Cap, Planarity

V-score / Tab-route

Panel breakaway methods (scored lines / tabs with mouse bites).

Panelization, Depanel

Void (BGA/thermal)

Gas pockets in solder; limited by % area rules.

AXI, Profile, N₂

Wave / Selective solder

Bulk THT solder processes (whole board / targeted nozzles).

Fluxing, Preheat, Bridging

WHMA-A-620

Acceptability standard for cable/wire harnesses.

Crimp height, Pull force

Window (process)

Range of settings where the process is stable (print/place/reflow).

DOE, SPC

Witness mark

Paint line across screw head and base to show if it moved.

Torque, Audit

WIP

Work In Process—units not yet complete; track by operation/state.

MES, Supermarket

X-out

Defective board in a panel marked to prevent use.

Panelization, Routing

XRF

X-ray fluorescence; measures plating thickness/materials.

Solderability, RoHS

ZIF

Zero-Insertion-Force FFC/FPC or socket with a latch.

FFC/FPC, Tug test