Samtec Ensures Product Quality Through Machine Vision Inspection

Personal computers are made up of many different components including processors, motherboards, memory, hard drives, etc.  PC manufacturers may advertise the largest hard drive, fastest processor, or most memory, yet the usability and reliability of the machine is dependent on the quality and reliability of the interconnects used between each internal component.  Samtec, Inc., an ISO-9001 registered, worldwide manufacturer of PC board-level electronic connectors,  uses automated, in-line machine vision inspection systems from PPT VISION, Inc. to ensure quality interconnect solutions to their customers. 


Samtec's manufacturing facilities in the United States, Scotland, and Singapore employ 900 people in the production of interconnects, including board-to-board, power-to-board, card-to-board, cable-to-board, and application-specific connectors, plus PGA, IC, and PLCC sockets.  In addition to personal computers, Samtec interconnects are used in telecommunications equipment, handheld devices, industrial controls equipment and medical equipment. Samtec, Inc. is renowned for their ability to accept an order for virtually any part in their catalog, manufacture it, and ship it within five days.  Popular connectors are shipped within one to three days after receipt of an order. They advertise this capability as Sudden Service.


Many electronic device manufacturers require their suppliers to inspect 100% of all supplied parts so shipments contain only defect-free parts. Steve Koopman, Manufacturing Engineering Manager at Samtec, said, "Inspection accuracy is a critical aspect of our business.  Faulty components result in device failure and damage the device manufacturer's reputation.  Our customers rely on us to provide reliable connectors". Some of the essential inspections for electronic connectors include pin presence/absence, coplanarity (the tip of each pin in the same plane as all other pins), and true position ( the correct position of each pin in relation to the connector housing and all other pins).  These features are critical to successful seating of the connector on the circuit board and mating of the connector to a cable, etc.



Samtec employees performed all part inspections manually until late 1999 when the company began producing tiny, high-density connectors.  Some of Samtec's high-density connectors can have up to 500 pins in multiple row configurations. With such a large quantity of small pins, the human eye is incapable of discerning coplanarity, so, despite a high degree of expertise within Samtec's inspection group, visual inspection of the new high-density connectors achieved an unacceptable accuracy level.


According to Koopman, "We needed a machine vision inspection system capable of discerning individual coplanarity among 500 tightly-grouped pins with 100% accuracy in order to provide the required quality for our new high-density connectors." Additional goals for machine vision inspection included reducing inspection labor hours and increasing the rate of throughput.


After months of research, Koopman selected Passport® DSL™ (Digital Serial Link) systems from PPT VISION, Inc. (Minneapolis, MN). Software, features, expandability, and PPT reliability, (proven by a PPT system purchased eight years earlier which is still in use) were the reasons for choosing Passport DSL systems.


Passport DSL systems use a patented, two-way digital serial communications network to achieve unprecedented inspection speed and accuracy, and offer quick and easy expansion capabilities. Up to 16 digital cameras can be connected to the processor using simple twisted-pair cables. The systems' Vision Program Manager™ (VPM) software includes the custom Connector Tool which features multi-image stitching, allowing users to zoom in on a small section of a connector and take several high-resolution images of the part on-the-fly as it passes under the camera. The software then "stitches" these images together into a complete view of the whole connector for increased inspection precision. The VPM software also streamlines Passport DSL setup by replacing lines of code with graphic programming tools that users "drag-and-drop" into a flowchart. Passport systems operate in the Windows™ environment for maximum networking and application compatibility.


Samtec's first Passport DSL system, now in use for ten months, provides rapid and reliable 100% part inspection of several of Samtec's products, including the Quad Row Staggered SMT Socket Assembly. The system also accelerates the resolution of production problems by alerting the operator to the first defective part. Samtec has integrated the Passport DSL systems with secondary assembly equipment, allowing them to perform 100% part inspection as a "throughput-free" operation. Part inspection is performed simultaneously with secondary assembly operations, such as pick-and-place pad application.


In addition to the original goals of increasing quality percentages and throughput speed, the Passport DSL has decreased scrap, re-work, maintenance time, and replacement part costs. According to Koopman, "Passport DSL may extend the useful life expectancy of our equipment by enabling us to detect production problems early so we can adjust and calibrate, rather than 'down' and repair."


Since the purchase and installation of the first DSL system, Samtec has purchased 8 more and is in various stages of implementation with each of them. Explaining future company plans for machine vision inspection, Koopman said, "We are currently reviewing all new assembly equipment for vision integration. We hope to automate the inspection process into the assembly processes."



This application note was provided by PPT Vision.  PPT VISION, Inc. is the world leader in the design and manufacture of completely digital 2D and 3D machine vision systems. Since our founding in 1982, we have specialized in industrial applications where accuracy, repeatability, high speed and flexibility are important requirements. For more information on PPT Vision, please visit their website at: