PCB Inspection & Testing Explained

PCB inspection and testing are essential steps in ensuring that a printed circuit board meets both quality and functional requirements.

While inspection focuses on detecting defects, testing verifies electrical integrity and performance.
Together, they form the final quality gate before PCB assembly or shipment.

This hub page provides an overview of the most important PCB inspection and testing methods and links to in-depth technical articles for each.

Quality foundation:
Förklaring av PCB-kvalitet och tillförlitlighet

Why PCB Inspection and Testing Matter

Even with robust manufacturing processes, defects can still occur.

Inspection and testing help to:

• Detect manufacturing errors early
• Prevent defective boards from reaching assembly
• Provide feedback for process improvement
• Reduce reliability and field failure risk

They do not replace good design or process control, but they significantly reduce risk.

Automatiserad optisk inspektion (AOI)

AOI is the most commonly used inspection method in PCB manufacturing.

What AOI Does Well

• Detects surface-level defects
• Identifies opens and shorts visually
• Improves inspection speed and consistency

AOI Begränsningar

• Cannot detect internal defects
• Cannot verify electrical performance

Deep dive:
AOI-inspektion vid tillverkning av mönsterkort

Inspektion med röntgenstråle

X-ray inspection enables visibility into the internal structures of a PCB.

What X-Ray Detects

• Via and hole plating voids
• Internal layer misalignment
• Delamination and resin voids

X-Ray Limitations

• Högre kostnad
• Slower inspection speed
• Typically sampling-based

Technical details:
Röntgeninspektion vid tillverkning av mönsterkort

Elektrisk testning av kretskort

Electrical testing is the only method that directly verifies connectivity.

What Electrical Testing Confirms

• Kontinuitet i alla nät
• Absence of shorts
• Korrekta nätanslutningar

What It Cannot Do

• Predict long-term reliability
• Detect internal voids or plating thickness

Method overview:
Elektrisk testning av kretskort förklaras

Flying Probe vs Fixture-Based Testing

Once electrical testing is required, choosing the right method becomes critical.

Key Decision Factors

• Produktionsvolym
• Design stability
• Kostnadsstruktur
• Time-to-market

Comparison guide:
Elektrisk provning med flygande sond eller fixtur

Inspection vs Testing — Understanding the Difference

Both are necessary, but they address different risks.

How Inspection and Testing Work Together

A complete PCB quality system typically follows this sequence:

1. AOI for early surface defect detection
2. X-ray inspection for internal structures (when required)
3. Electrical testing for connectivity verification
4. Reliability testing for long-term performance (selective)

Reliability link:
Förklaring av tillförlitlighetstestning av kretskort

Cost Considerations in Inspection and Testing

Inspection and testing add cost, but skipping them increases risk.

Cost is influenced by:

• Styrelsens komplexitet
• Volym
• Inspection depth
• Val av testmetod

Cost balance:
Avvägningar mellan kostnad och kvalitet vid tillverkning av mönsterkort

When Enhanced Inspection Is Necessary

Enhanced inspection and testing are especially important for:

• Kretskort med hög densitet eller flera lager
• Nya konstruktioner eller material
• High-voltage or high-temperature applications
• Produkter med lång livslängd

I sådana fall är enbart standardinspektion otillräcklig.

I sådana fall är enbart standardinspektion otillräcklig.

How Manufacturers Apply Inspection in Practice

In real production environments, inspection strategies are tailored to:

• Design risk
• Volume economics
• Customer requirements

At TOPFAST, inspection and testing methods are selected based on risk level and application needs, ensuring both efficiency and reliability.

Slutsats

PCB inspection and testing are essential safeguards that bridge manufacturing processes and real-world performance.

By combining AOI, X-ray inspection, electrical testing, and appropriate test strategies, manufacturers can significantly reduce defect risk and improve overall PCB quality.

This hub page serves as the central reference for the Inspektion och testning av kretskort ämneskluster.

PCB Inspection & Testing FAQ