Connectors for medical imaging equipment

Connectors must function at higher speeds, provide higher density, require lower profiles, and meet ever-stricter standards

BY GIJS WERNER
FCI
Etters, PA
http://www.fciconnect.com

As performance expectations for test equipment in the medical industry are heightened, the component technology required by medical equipment OEMs is expected to meet and often exceed those demands. Doctors rely on test equipment to provide more information more accurately and in a shorter time frame, and the connectors used in this equipment can play a key role in making that possible.

Continuous improvements in the medical imaging segment are driven by the need for more accurate and easier-to-use technologies. Increasing demands on new medical imaging equipment are driven mainly by investments in scanning systems by hospitals, replacement of older outpatient facilities, replacement of conventional analog x-ray machines by digital systems, growth in diagnostic ultrasound equipment, and the trend to combine different technologies within the same equipment, like CT and MRI.

As medical testing and procedures become more advanced, the electronic components designed into the equipment must be more than just reliable in critical applications. Connectors in today’s medical applications must function at higher speeds, provide higher density, require smaller footprints and lower profiles, and meet ever-stricter industry standards.

Scalability

Despite the advanced technology, medical imaging systems are more affordable than ever before. Part of the drop in end-product prices is due to the shrinking of overall system size.

To meet that need, connector manufacturers have significantly increased the density of their products, packing more speed and performance into less space. More important, design engineers can prevent the need for complete system redesigns by making systems upgradable to keep pace with market trends, making scalability an important feature in today’s components.

Size

The miniaturization of connectors in the medical industry is being driven by that same trend in equipment such as mobile monitoring stations and handheld equipment like field-operable CT scans or laptop-sized portable ultrasound systems, which aid in the trend toward outpatient treatment over in-hospital stays. In the past, using these connectors typically meant a lower level of electrical performance. However, connector manufacturers have developed more advanced solutions to meet performance requirements, such as connectors or connector arrays on flex foil.

Used to connect the photodiode within the scanner, higher-density connector arrays allow a greater number of slices, resulting in more accurate imaging. Some such connectors deliver achieve data rates of up to 10 Gbits/s.

High-density mezzanine connectors also stand out for many of the leading medical digital imaging equipment manufacturers, in both hospital systems and portable scans, in particular. Mezzanine connectors provide the performance features needed for MRI, CT, and other imaging applications to achieve real-time higher-resolution imaging. It appears mezzanine connectors with BGA attachment are preferred over SMT because BGA suits medical manufacturing processes best.

Speed

Higher-speed requirements are a result of the desire for real-time diagnoses, increased accuracy, and faster imaging (to ensure patient safety and to make diagnostics more effective). There is also a need for improved functionality for machines that combine previously separate systems, such as positron emission tomography and computer tomography. And, in ultrasound systems, new diagnostic imaging technology enables systems to move from 2-D to generally preferred real-time 3-D/4-D imaging – thus requiring higher data transmission speeds to compile and display all information.

Speed is a fundamental design parameter that has system-wide implications, from board-level to PCI bus. It is important that OEMs choose component suppliers that understand these end-product requirements because choosing the right connector can save time during the design and testing process that can be spent on other aspects of the system.

Components that provide increased performance, such as connectors that are ideal for high-speed applications, can help bring down the overall cost of medical imaging systems (like an ultrasound machine) every single year because as the performance of an individual connector increases, fewer are required for the overall design.

Standards

As the medical industry adopts new standards for its equipment, machines need to meet certain specifications such as USB, PCI, RJ45, DVI, MicroTCA, and PCI Express. The internal components being incorporated for both new designs and upgrades must also meet these standards, which typically are coming from data or telecom applications.

The growing implementation of such specifications can be attributed to their facilitation of shorter design cycles, faster system introductions, and the fact that open standards technology offers ready-made solutions to expanding connectivity requirements. OEMs are often pushed to “experiment” with new architectural options, which can make even the latest electronic components quickly obsolete.

Because of this, OEMs prefer to avoid proprietary systems because they result in higher costs and longer development cycles (up to seven years for a new generation of MRI scan to be introduced, for example). Components that do not readily work with a specified architecture can create additional lag time and affect overall design.

The product lifetime of medical equipment is relatively long so the ability to scale up and upgrade via open standards, as well as a high level of reliability, are essential elements of the equipment’s performance, especially for complex and expensive combined-modality systems that require constant use to provide proper payback. If the interconnectivity selection has been carefully made with an eye on open standards and future product road maps, increasing functional and financial needs of medical equipment will be met.

In some cases, the components used in the adopted standards may not be a perfect fit for medical applications. A good example of this is PCI Express, now the connector standard of choice for PC-based systems, which has gradually found its way into medical equipment as well. Where we used to see many proprietary systems, the open PCIe standard is being applied more and more, especially in ultrasound systems.

Traditionally, ultrasound systems have used standards-based architectures like CompactPCI bus or VMEbus, but with the backplane performance hitting the limitations of standard architectures, there is a clear need for connector technologies that offer higher performance and higher reliability at a reasonable cost. ■

For more on connectors, visit http://electronicproducts-com-develop.go-vip.net/packaging.asp.