through-hole assemblies

EI provides robust through-hole assembly solutions for high-reliability applications, using automated selective soldering to ensure strong mechanical bonds and long-term durability in mission-critical systems.

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robotic selective soldering

Precision-controlled soldering for through-hole components—ideal for mixed-technology boards and heat-sensitive assemblies.

Red circuit diagram with a central circle and connecting lines ending in smaller circles.

wave soldering

Efficient, high-volume soldering method that delivers consistent, durable joints for through-hole assemblies—EI supports both leaded and lead-free solder wave processes to meet diverse industry and compliance requirements.

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aoi inspection

Automated Optical Inspection (AOI) detects defects and verifies placement accuracy to ensure consistent quality and performance.

advantages of through-hole assemblies

Strong Mechanical Bonds:  Through-hole components are soldered through the board, creating secure connections ideal for high-vibration or high-stress environments.

Superior Durability:   These assemblies hold up well under thermal and mechanical strain, making them perfect for rugged applications.

High Power Handling:   Through-hole technology supports larger components and higher current loads, making it ideal for power electronics.

Reliable Manual Adjustments:   Easier to modify or replace during prototyping, testing, or field servicing compared to surface-mounted parts.

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 through hole assemblies

medical

We provide robust through-hole assembly for medical devices requiring secure connections and long-term dependability.

industrial

EI Micro’s through-hole solutions are ideal for industrial applications demanding mechanical strength and extended lifecycle performance.

energy

Our precision through-hole assemblies support high-voltage, high-power energy systems with durable component anchoring.

agriculture

We deliver field-tough PCB assemblies for agtech equipment using through-hole techniques built for rugged use.

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

Aviation-grade through-hole assembly ensures flight electronics are vibration-resistant, reliable, and built to spec.

military

EI Micro manufactures military PCBs with through-hole construction designed for shock, thermal, and mission resilience.

Security and Surveillance

We build through-hole assemblies that provide secure, long-lasting connections for 24/7 surveillance and defense 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."

Two women in lab coats soldering at a workbench. One has gray hair and glasses.

Through-Hole Assembly FAQs

  • When should through-hole components be used instead of SMT components?

    Through-hole components are often selected when an assembly requires strong mechanical attachment, particularly for connectors, transformers, switches, relays, and other components exposed to insertion or mechanical forces. Many PCBAs combine through-hole and SMT components.

  • Can through-hole and surface mount components be used on the same PCB?

    Yes. Mixed-technology PCB assemblies routinely combine SMT and through-hole components. The manufacturing process must account for component sequence, soldering requirements, thermal limitations, accessibility, and inspection.

  • What is the difference between wave soldering and selective soldering?

    Wave soldering exposes a defined board area to a solder wave and is effective for suitable through-hole assemblies. Selective soldering applies solder to targeted locations, providing greater process control when through-hole components are located near heat-sensitive or previously installed SMT components.

  • What causes through-hole solder joint defects?

    Potential causes include insufficient hole fill, poor wetting, incorrect thermal profiles, contamination, component lead conditions, and excessive or insufficient solder. Process controls and inspection help identify these conditions before assemblies move to final test.

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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.