Technical Information

A Production ready PCB must take into account the various machine automated processes it will undertake during the manufacturing process.

When laying out a PCB for production, please take into account the following inclusions in the design file.

Bill of Materials (BOM)

• Ensure that components on the PCB are all in the Bill of Materials (BOM)
• If a component is not required – enter Do Not Fit (DNF) in the BOM column
• BOM must have a Designator Column for components, i.e SMD, THD, other
• BOM Component Description should be complete, e.g. CAP, 100nF 100V 10% X7R, 805
• BOM should list the Part Number & Manufacturer of each component
• BOM should identify where substitute components are allowed

PCB Fiducials

• There must be at least 3 Fiducials for each PCB side containing SMD
• If SMDs are on both sides of PCB then fiducials are required on both sides
• Fiducials must be on EACH PCB that is in a Panel
• Fiducials must be at least 7.0mm from the outside edge of tooling strips
• Fiducials are normally a 1.00 mm diameter solid round exposed metal pad with a 1.0mm soldermask pullback
• Localised fiducials on fine pitched components (< 0.50 mm) is recommended

Components to be loaded on PCBs are divided into 3 separate areas. Surface Mount components, Through Hole components and Custom components.

It is important to identify to the manufacturer the existence of Custom components in the BOM which will require special placement techniques.

Surface Mount Technology (SMT)

• Component Size – Minimum: 0.6 x 0.3mm (0201)
• Component Size – Maximum: 56.0 x 56.0 x 15.00mm
• Component Weight – Maximum: 80 grams
• Footprint – Minimum pad size: 0.30mm**
• Footprint – Minimum pitch: 0.40mm**
• *Smaller pad and pitch size will require an Electroformed Solder Stencil
• Pick & Place SMT Connectors must have vacuum pickup dot attached

Through Hole Technology (THT)

• Lead cutting & bending components must be on tape reel
• Polarized components must have direction marking clearly identified
• Press fit components should have jig supplied

 

Custom Components

• Should be identified in the BOM as ‘special fit’
• Any special requirements – soldering, gluing or other should be identified
• Insulation component barriers should be identified

A production PCB is normally panelised so as to accomodate the mechanised transport systems used in the various production stages. These will include, Pick & Place, Through Hole Solder, Automated Optical Inspection and Conformal Coating.

A production panel always includes tooling strips which allow the panel to go onto the mechanised transport systems.

PCB Panels

• Panel Size Maximum: 443 x 508mm
• Panel Size Minimum: 70 x 50mm
• Panel Thickness: 0.4 – 6.0mm
• Top side clearance: 12.5mm
• Bottom side clearance: 20.0mm
• Maximum Board warp/bow/twist 2.0mm
• Tooling strips – Minimum: 10.0mm
• Fiducials on tooling strips must have minimum clearance from the edge of 7.0mm.