pcb inspection

EI Microcircuits performs multi-level PCB inspection using AOI, X-ray, and manual verification to ensure precision, quality, and compliance. Every board is carefully evaluated to meet the highest industry and customer standards.

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optical inspection

Automated Optical Inspection (AOI) detects misalignments, solder defects, and component issues with high-speed imaging and accuracy.

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x-ray inspection

X-ray inspection allows us to verify solder joints and internal connections beneath BGAs and other hidden components.

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3D Solder paste inspection

We use 3D SPI to measure solder paste volume, height, and alignment—ensuring a strong foundation for reliable soldering.

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ict testing

ICT verifies electrical performance, identifying shorts, opens, and component values to ensure every board meets functional specs.

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functional testing

Our functional tests simulate real-world conditions to confirm final assemblies perform exactly as intended.

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flying probe testing

Flying probe testing offers flexible, fixture-less validation—ideal for low-volume runs. EI’s in-line systems deliver fast, accurate diagnostics with streamlined efficiency.

certified excellence you can trust

Partner with EI Microcircuits—certified to the highest industry standards and trusted across medical, defense, and industrial markets for precision, quality, and compliance.

applications FOR pcb Inspection

medical

Our multi-stage inspection process ensures every medical PCB meets strict regulatory and quality standards.

industrial

We apply rigorous inspection protocols to validate durability and performance in high-load industrial applications.

energy

EI Micro’s inspection systems verify PCB reliability in energy environments where uptime is non-negotiable.

agriculture

We inspect every agricultural PCB for resilience and precision—so your equipment performs in any condition.

EI Microcircuits builds high-layer count, high-performance assemblies for the emerging AI market. Our advanced SMT and quality systems ensure reliable, complex builds for HPC applications.

aviation

Our aviation PCB inspection process is built on traceability, documentation, and flight-critical quality control.

military

Military-grade inspection protocols confirm every assembly meets mission-ready standards under the harshest conditions.

Security and Surveillance

We conduct thorough inspections to guarantee real-time performance and reliability in surveillance and security systems.

through-hole

Durable, high-reliability assembly for rugged and high-power applications.

inspection

Ensures precision, quality, and compliance at every production stage.

box build

EI offers a wide range of box build services including full electromechanical assembly.

overmolding

EI offers premolding and overmolding of a wide variety of materials in house.

potting

Protects electronics from moisture, vibration, and harsh environmental conditions.

our certifications

ISO 13485:2016 certified badge, AMTIVO logo, text "Medical Devices".
Logo for AMTIVO. ISO 9001:2015 Certified for Quality Management. Features a stylized "A".
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hear it from our customers

"A delightful company to work with. Could not have done it without your expertise."

"EI excels in responsiveness, support and flexibility. I very much appreciate EI’s ability to adapt on the fly."

"I appreciate the work EI does most of all because it makes my job easier."

"Overall, EI does a great job in dealing with everything we throw at them. They are responsive and understanding of us, even though it may not always be the most reasonable of requests. As a buyer, I feel lucky to have a supplier that works with us like they do."

"Working on a project that had a board that was simply not manufacturable the way it was set up, EI went above and beyond to help with engineering and still met a very short deadline."

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PCB Inspection FAQs

  • What is the difference between AOI and X-ray inspection?

    Automated Optical Inspection evaluates visible component placement and solder conditions using imaging systems. X-ray inspection evaluates connections that cannot be adequately seen optically, including solder joints beneath packages such as BGAs and QFNs.

  • When is X-ray inspection needed for PCB assemblies?

    X-ray inspection is particularly useful when solder connections are hidden beneath components or when an assembly requires evaluation for internal conditions such as voiding, bridging, or incomplete solder connections.

  • What PCB defects can AOI detect?

    AOI can identify many visible assembly conditions, including missing or misaligned components, polarity errors, solder bridging, insufficient solder, and certain solder-joint defects. Inspection criteria must be matched to the assembly and applicable workmanship requirements.

  • Is visual inspection enough for high-reliability PCB assemblies?

    Visual inspection alone may not provide sufficient coverage for complex assemblies. Depending on the design and requirements, inspection can be combined with AOI, X-ray, in-circuit testing, flying probe, and functional testing to provide a more comprehensive quality strategy.

Electronic Insights

Gold-colored printed sheets on a large press machine in a workshop

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Meta description: Learn how to navigate the PCB laminate shortage with DFM, material planning, and production strategies from EI Microcircuits.
Person soldering a green circuit board on a workbench with tools nearby

PCB Material Selection Guide

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PCB Material Selection impacts performance, reliability, and manufacturing. Learn key material considerations and applications with guidance from EI Microcircuits.
Blue circuit board overlaid on technical schematics with a central chip and small components

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Learn how PCB layout impacts performance, manufacturability, testing, and long-term reliability with expert insights from EI Microcircuits.

let's talk

EI Microcircuits operates multiple climate-controlled facilities designed for scalability, technical excellence, and built-in disaster resilience—each fully equipped to support today’s most advanced electronic assemblies. Let us be the solution to your next project—Contact Us, Request a Quote, or Schedule a Tour today!

Contact Us Today

MANKATO, MN

1651 Pohl Road
Mankato, MN 56001
P: 507.345.5786

ST. PETER, MN

2011 Klein Street
St. Peter, MN 56082
P: 507.934.5722

MANKATO, MN

69 Power Drive
Mankato, MN 56001

P: 507.386.9160

*Each facility is configured to support your production needs. While maintaining continuity with each other in equipment, training and process control. All facilities share the same data center to allow for seamless manufacturing between locations.