China & Thailand PCBA manufacturing support

PCB assembly required files

Prepare your PCB assembly files.

Combine your Gerber data, centroid file, BOM, assembly drawings and panel working Gerbers in one ZIP package. A complete input set helps engineering review manufacturing, sourcing and placement together.

Separate consultation, quotation and production release

You can start a discussion with incomplete files. Mark missing or inapplicable items explicitly; engineering should define what is required for the proposed scope.

On small screens, scroll the table horizontally.

Review areaInformation to prepare or requestDecision or record
Early consultationProduct purpose, stage, quantity and the unresolved questionDescribe missing files without pretending they are ready
Quotation reviewBoard revision, BOM, supply model, quantity and acceptance scopeAdd placement, drawings and test information as available
Production releaseApproved data, alternatives, fixtures/firmware and final acceptance criteriaPanel data is applicable only when the agreed build uses a panel

Interactive preflight check

Is your file package ready?

Check each item as you prepare the ZIP. This local checklist stays in your browser and does not upload any data.

0of 8 ready

Start with the approved design revision.

Five-file package guide

See what each file controls in production.

Choose a file type to see why engineering needs it, which information it should contain and where it is used on the factory floor.

KeepBest company photograph: board inspection reference
01 / Fabrication and stencil data

Complete Gerber layer package

Include outline, copper, soldermask, silkscreen, solder paste and drill information so the board and assembly tooling can be reviewed together.

Board outlineCopper layersSoldermaskSilkscreenPaste and drill data
Read all five file requirements

Complete Gerber layer package

Include outline, copper, soldermask, silkscreen, solder paste and drill information so the board and assembly tooling can be reviewed together.

  • Board outline
  • Copper layers
  • Soldermask
  • Silkscreen
  • Paste and drill data

Centroid / pick-and-place file

Provide component locations, rotations and reference designators so placement programs can be prepared and checked against the BOM.

  • Reference designator
  • X coordinate
  • Y coordinate
  • Rotation
  • Top / bottom side

Sourcing-ready BOM in Excel

A structured BOM helps engineering and purchasing align quantity, manufacturer part number, description, technology and package for every fitted component.

  • Reference designators
  • Quantity
  • Manufacturer part number
  • Description
  • Type and package

Assembly drawings and notes

Drawings communicate polarity, component orientation, fitted or not-fitted positions, mechanical details and any special assembly instructions.

  • Polarity
  • Orientation
  • Do-not-fit parts
  • Mechanical notes
  • Special instructions

Working Gerbers for panelized boards

When the PCB house has panelized the boards, provide its working Gerbers so the actual production panel can be used to prepare the SMT stencil.

  • Final production panel
  • Fiducials
  • Tooling rails
  • Board spacing
  • Stencil alignment
5 layers visibleClick below to inspect the file stack

Illustrative layer stack. The drawing is a file guide, not a manufactured board photograph.

01 · Gerber files

Include every layer needed to build and assemble the board.

Gerbers translate your layout into manufacturing images. Clear naming and a complete layer set reduce the risk of interpreting the wrong side, finish or revision.

  • Board outline and mechanical information
  • Top, bottom and inner copper layers
  • Top and bottom soldermask layers
  • Top and bottom silkscreen layers
  • Solder paste layers and drill data where applicable

03 · Bill of materials

Make every BOM line purchasable and traceable.

Excel is the preferred working format. The more precise the manufacturer part number and description, the fewer sourcing assumptions are required.

KeepBest company photograph: component storage

From spreadsheet to controlled material

Your BOM drives purchasing, kitting and inspection.

Part identity must remain aligned from quotation through incoming inspection and production release.

Learn about PCB BOMs

Recommended BOM columns

These six data groups help engineering and purchasing prepare an accurate component review.

01
Reference designatorsR1, R2, C15, U3
REQUIRED
02
Quantity per assemblyNumber required for each component line
REQUIRED
03
Manufacturer part numberExact orderable component identity
REQUIRED
04
Part descriptionValue, rating, tolerance and key characteristics
REQUIRED
05
Assembly typeSMT, through-hole, BGA or other technology
REQUIRED
06
Package description0805, SOIC, QFN and similar package information
HELPFUL
Also identify do-not-fit lines, approved alternates and customer-supplied parts when applicable.

02 + 04 · Placement and build guidance

Coordinates tell machines where. Drawings tell people how.

The centroid file and assembly drawing answer different questions. Providing both helps cross-check component identity, position, orientation and special build requirements.

KeepBest company photograph: placement operation reference
Centroid / Pick & Place

Component locations, rotations and reference designators.

Use consistent units and clearly identify top and bottom placement sides.

RefDes
U3
X
34.520
Y
18.260
Rotation
90°
KeepBest company photograph: manual assembly reference
Assembly drawings

Visual instructions for polarity, orientation and special handling.

Include drawings when they clarify do-not-fit positions, connectors, mechanical hardware or customer-specific notes.

PolarityOrientationDNP / DNIMechanical notes

05 · Working Gerber files

Panelized boards need the final production panel data.

If your PCB supplier panelizes the boards, include the working Gerbers generated by that PCB house. These reflect the actual panel used to fabricate the SMT stencil.

  1. Export the approved single-board Gerbers.
  2. Obtain the final panelized working Gerbers from the PCB house.
  3. Keep panel revision, outline, fiducials and tooling rails aligned.
  4. Place the working data in the same ZIP as the assembly files.
The stencil should be prepared from the production panel—not from an earlier or differently arranged board file.
PACKAGE FORMATOne ZIP fileKeep matching revisions together
PLACEMENT DATAX · Y · Rotation · RefDesCentroid / pick-and-place file
SOURCING DATAMPN · Qty · DescriptionExcel BOM recommended
PANELIZED BOARDSWorking GerbersSupports SMT stencil preparation

A cleaner engineering handoff

From files to a production review in three steps.

A complete package lets engineering connect design data, component information and assembly requirements before quotation and release.

Engineering team reviewing project files
01

Prepare one ZIP package

Keep Gerber, centroid, BOM, drawings and panel data on the same approved revision.

Component material and sourcing control
02

Add commercial requirements

State quantity, target schedule, sourcing responsibility and any test or programming needs.

Factory engineering and inspection review
03

Engineering checks the route

Manufacturing, placement, component and inspection inputs are reviewed together for quotation.

Required files FAQ

Avoid the most common handoff gaps.

Clear file names, matching revisions and complete manufacturing data help prevent unnecessary clarification cycles.

Should all files be placed in one ZIP package?

Yes. A single ZIP keeps the manufacturing and assembly inputs together. Use clear file names and keep every file on the same approved revision.

What must the centroid file contain?

Include component X and Y locations, rotation, reference designators and preferably top or bottom placement side.

Which format should I use for the BOM?

Excel is preferred because structured rows and columns are easier to review, source and compare. Include exact manufacturer part numbers wherever possible.

Are assembly drawings always required?

Include them when available. They are particularly useful for polarity, orientation, do-not-fit parts, connectors and mechanical instructions.

Why are working Gerbers needed for panelized boards?

The final working Gerbers from the PCB house represent the production panel and help fabricate the SMT stencil against the correct layout, fiducials and rails.

Prepare your review package

Prepare your review package.

Include project quantity, assembly type, testing needs and the target schedule. The team can then review the manufacturing and quotation inputs together.

One ZIP package recommendedCombine related files with clear names; confirm transfer limits with salesOther formats can be sent by email

Send a project enquiry

* Required
    ZIP, Gerber/drill, CSV, XLSX or PDF · up to 10 files, 10 MB each, 20 MB total.
    Files are stored privately for project review.

    Get A Quote

    Fill in your requirement information and upload Gerber and BOM files, we will give you a quote within 24 hours.

    Get A quote

    Fill in your requirement information and upload Gerber and BOM files, we will give you a quote within 24 hours.