Introduction

For electronics engineers and designers, ordering custom printed circuit board (PCB) manufacturing is an inevitable step in product development. While PCB costs represent only one component of the total budget, understanding realistic cost expectations helps with planning and budgeting your project.

This article will provide a comprehensive guide to the key factors that influence PCB costs including size, layer count, complexity, pre- and post-processing, and quantity. We will look at how pricing breaks down among raw materials, labor, and profit margins. You will gain the knowledge needed to estimate order expenses and reduce unnecessary costs for your next PCB fabrication.

Base Material Costs

The raw PCB materials make up a significant portion of costs:

Laminates – The fiberglass-reinforced sheets form the substrate. More exotic materials increase costs.

Copper Foil – Thicker copper is more expensive. 1oz/ft2 is standard, while 2oz+ adds cost.

Masking Materials – Liquid photoimageable soldermask and silkscreening add expense.

Plating – Gold increases cost far above standard HASL, ImmSn, or ENIG finishes.

Vias – Blind and buried vias require additional drilling and plating steps.

Frugal designers select affordable options like FR-4 laminates and 1oz copper wherever the design permits.

Size Factors

Board size impacts both material and processing costs:

Area – Larger boards use more base materials. Panelizing optimizes cost.

Edge Length – More complex tooling and handling increases edge costs.

Thickness – Standard 1.6mm is lowest cost. Thicker boards get pricier.

Tolerances – Tighter tolerances require more precise (costly) equipment.

High Density – Dense components or traces drive upgrades to manufacturing capabilities.

Strict area and tolerance budgets keep size-driven costs at reasonable levels.

Layer Count Considerations

Layer count significantly influences cost:

Layer Count – Each additional conductive layer adds expense through materials, lamination, and drilling.

Blind/Buried Vias – Each blind via adds 1-2 drill steps. Buried vias require even more.

Stacked Vias – Each stacked via adds 2+ drill cycles depending on depth.

High Aspect Ratio – Deeper drilling increases tool wear and cycle time costs.

Thick Boards – Thicker boards make drilling more difficult and time consuming.

Additional layers should only be used where dense routing and isolation necessitates. Creative routing and via strategies help minimize layers.

Design Complexity Factors

Complex PCB designs demand more fabrication processing:

Fine Features – Trace/space under 6 mil requires advanced capabilities.

High Component Density – Dense parts require smaller tooling and more handling.

Mixed SMT/Through-Hole – Adds solder paste, component installation, soldering steps.

Buried Components – Add steps to embed components in cutouts.

Flex Circuits – Flex PCBs add cost for flexible materials and processes.

HDI Techniques – Blind/buried vias, microvias, and tighter features use exotic processes.

Simplifying layouts by minimizing density, component types, and feature sizes streamlines manufacturing and cost.

Pre-Processing Operations

Some optional preprocessing steps add cost:

Carbon Ink Resistors – Screen printing carbon composition resistors.

Graphite Coatings – Applying lubricious graphite layers.

Peelable Mask Layers – Temporary peelable solder masks.

Buried Capacitance – Building up additional dielectric/copper layers.

Gold Edge Plating – Edge connectors require selective gold plating.

Beveling/Routing – Shaping raw boards by CNC adds setup.

Solder Paste Stencils – Stencils for SMT solder paste application.

Press-Fit Layers – Press-fit mechancial layers increase lamination cycles.

Embedded Components – Cutouts and cavities for embedding components.

Carefully evaluate if any preprocessing features are absolutely required or simply “nice-to-have” extras that inflate cost.

Post-Processing Operations

Post-processing steps performed after board fabrication also add cost:

Cleaning – Removing post-etch residues and debris.

Coatings – Conformal coatings for insulation and protection.

Selective Plating – Localized electroless nickel/gold plating.

Selective Silkscreening – Additional silkscreen layers or selective application.

Laser Trimming/Drilling – Cutting, skiving, or drilling with lasers.

Inspection/Testing – Automated optical, x-ray, or netlist circuit testing.

Assembly – Load, solder, and attach any specified components.

Box Builds – Installing boards into cases or racks with cabling.

Review whether post-processing could be performed more economically yourself after receiving finished boards.

Order Quantity Impacts

Volume substantially influences overall price:

Low Volume – High engineering and setup costs are distributed over fewer boards.

Medium Volume – Amortizes costs over more units to reduce per board expense.

High Volume – Best economy of scale. Reduces material, labor, and overhead per board.

One-Off prototype – Very high cost due to engineering, custom tooling, and handling.

Small Batch – Lower cost than prototype, but still ineffecient compared to higher volumes.

To minimize costs, aggregate orders into larger batches and negotiate price breaks on volume.

Labor, Overhead, and Profit

Beyond materials, manufacturing PCBs incurs labor, facility, and business costs:

• Engineering – Design review, DFM analysis, documentation, testing
• Tooling – Fabricating masks, stencils, fixtures, pallets
• Programming – Generating machine toolpaths, assembly data packs
• Labor – Machine operation, assembly, inspection, and handling
• Utilities – Electricity, gases, chemicals, ventilation
• Facilities – Space, maintenance of cleanrooms and EM shielding
• Certifications – ISO, ITAR, QPL, UL, Mil Standards, etc.
• Profit Margin – Margin to sustain the business and investment

These costs accumulate across small and large volume orders. Understanding the manufacturing ecosystem helps set realistic expectations when purchasing PCB services.

Cost Reduction Strategies

Here are ways to reduce PCB costs within your control as a designer:

• Standardize on commonly available materials like FR-4 wherever possible.
• Minimize board dimensions through efficient layout techniques.
• Reduce layer count by creative routing and combining circuits.
• Use moderately sized traces and gap widths suited to capabilities.
• Match specs to fab process capabilities and avoid exotic processes.
• Consolidate orders to mass quantities for better economy of scale.
• Standardize processes across designs for consistent pricing.
• Build relationships with vendors to negotiate better long term pricing.

While fabricators determine baseline pricing, smart design choices make a big impact to the final cost.

Conclusion

Estimating PCB fabrication expenses involves factoring together the costs of materials, sizes, layer counts, features, pre- and post-processing, order quantities, overhead, and reasonable profit margins. While intricate boards or exotic processes can become quite costly, following design-for-manufacturing guidelines helps restrain cost. Building partnerships between designers and their PCB vendors allows balancing performance needs with budget realities. With an understanding of the key drivers determining prototype, small batch, and production costs, you can make informed decisions and develop cost-optimized boards.

Frequently Asked Questions

Q: What are typical PCB costs per square inch?

A: As a rough estimate, lower complexity boards can range from $1-5/in2, moderately complex $5-15/in2, and multilayer high complexity from $15-50/in2 or more.

Q: How can PCB costs be reduced without sacrificing quality?

A: Strategies like standardizing processes, consolidating orders, panelizing boards, removing non-essential layers, and designing within fab capabilities reduce cost substantially.

Q: What are the most expensive PCB materials?

A: Thick multilayer boards, RF materials like Rogers, flexible circuits, and boards requiring embedded components or HDI techniques tend to be among the higher cost materials.

Q: Is it less expensive to order from local or overseas PCB manufacturers?

A: For moderate to high volumes, overseas fabs traditionally offer substantially lower pricing, though local suppliers are narrowing the gap and provide quicker turnaround.

Q: Can PCB fabrication quotes be negotiated?

A: Definitely. Volume discounts, preferred customer pricing, and dropping unneeded services gives flexibility for negotiating lower pricing on PCB orders.