Originally Published MPMN October 2001

PRODUCT UPDATE

Developments in Device Connectivity

From right-angle interconnects for use in harsh environments to wireless solutions, these suppliers have the right connections

Reliable performance, flexibility, safety, and ease of use are among the primary concerns of device manufacturers sourcing connectors, according to suppliers. OEMs want assurances that "continuous performance will not be compromised, and that our products are sufficiently adaptable for custom applications and to mate with other manufacturers' products," says ODU-USA Inc. application engineer Ric Miller. Availability is also a key issue, he adds, noting that short delivery times are a point of pride at his firm.

Considering the end-use environment, safety is equally important, adds Deby Forster, creative services manager at Fischer Connectors. That was a prime consideration behind the development of the SureGrip housing on the company's medical-grade products.

Meanwhile, in the wireless world, an Internet-enabled implantable device developed by Medtronic is a clear indication that the above concerns can be adequately addressed by next-generation technology. This predicate device will spur the development of wireless healthcare products, according to Jerry Klintz, program director at Colorado MEDtech.

Whether you are sourcing connectors or other electronic components, the accompanying Buyers Guide grid starting on page 58 provides a comprehensive listing of suppliers complete with contact information and a description of their core products.

The right angle for harsh environments

The Minisnap line of miniature connectors developed by ODU-USA Inc. features a push-pull locking mechanism that enables mating even in hard-to-reach places. The latching fingers hook into a groove inside the receptacle, making unintentional separation almost impossible. A right-angle connector for medical electronic equipment and instrumentation is one of the most recent additions to the product line.

Designed for use in harsh environments, the IP68 K-series connectors are "watertight and impervious to outside contaminants," stresses application engineer Ric Miller. "The housing and locking system of the Minisnap connectors protect the contacts from outside mechanical influence, impurities, dust, and unintended contact with and penetration of moisture, water, and other liquids."

Available in two sizes with 2- to 14-contact configurations, the connectors are designed to mate with most industry-standard products. To achieve this compatibility, "the K-Series housings have a larger diameter [than other models]," says Miller. To ensure that they remain watertight, cable grommets and seals are used, he adds. The plugs can also be potted to maintain watertight properties in unmated conditions.

The firm also recently introduced a size-4 connector that is designed for applications requiring a larger contact size or greater number of contacts. It is available with a plastic or metal housing and, like the K-series connectors, mates with most standard interconnects.

The K series comes with solder PCB pins, solder cup, or crimp contacts; the size-4 model has solder contacts.

Minisnap connectors have been tested for electromagnetic compatibility using the inductive wire (or parallel wire) method in accordance with procedure VG 55214-6-2. Documentation showing that the products achieve lower than –55 db attenuation is available. The connectors can be supplied in standard or autoclavable versions that withstand 1500 sterilization cycles.

Miller notes that ODU is currently focusing on expanding its line of plastic connectors. There is a growing demand for "lightweight, low-cost plastic connectors, and that has necessitated new housing designs, sizes, and contact configurations," he says.

Housings help users get a grip

Also striving to meet demand from the OEM marketplace for miniature plastic connectors, Fischer Connectors offers models with up to 19 gold-plated contacts. They incorporate a reliable push-pull positive-locking mechanism and offer a degree of protection equal to the IP68 standard. The impact-resistant plastic housing and plug body can be securely gripped, even if the user has wet hands or is wearing gloves.

The connectors are available in versions with 2 to 19 gold-plated contacts, and they feature a self-aligning keying system that was developed by Fischer in the early 1950s. "The Fischer keyway prevents the user from mating the two parts unless they are correctly aligned," explains creative services manager Deby Forster. Color-coding options are available, and the products have been tested to 5000 mating cycles.

"Medical device OEMs demand safety, quality, sterilizability, compliance to standards, and ease of use from their connectors," says Forster. In that respect, this series of connectors is suited for healthcare applications, she adds, because it "uses a durable plastic housing that withstands sterilization and an insulated construction that ensures safe operation for doctors, nurses, and patients," she says.

The wireless revolution

An implantable heart-monitoring device that Medtronic demonstrated at the North American Society of Pacing and Electrophysiology conference in Boston in May is great news for patients with a cardiac condition. The Chronicle, which is not yet on the market, will be able to transmit critical data to secure Internet sites. This will enable physicians to determine from a remote location whether the patient's heart has had an event, and the frequency and duration of those events. Being able to determine at a distance whether a face-to-face consultation is necessary adds a new measure of convenience and safety to implantable devices. For Jerry Klintz, program director at Colorado MEDtech, the Chronicle represents even more than that: it is a predicate device that will usher in an era of wireless healthcare products.

The company presented its vision of wireless connectivity at this year's MD&M exposition in New York City. In its booth, Colorado MEDtech installed a mockup of an intensive-care unit with a communications technology platform that monitored and controlled vital-signs units, IV pumps, and other devices. "We were demonstrating the capability not only of transmitting and receiving medical device data through a wireless connection," says Klintz, "but also the transmission of commands back to those devices." Klintz notes that there are still some security and safety issues that must be resolved before this technology can be made generally available, but, he adds, "we are on the verge of succeeding."

Colorado MEDtech also displayed its Link It technology, which connects new and legacy devices to the World Wide Web to enable remote software upgrades and to provide access to clinical data. "It converts protocols from legacy instruments via an RS-232 connection into a packetized 802.EEE Ethernet. Then, we can add a wireless connection, if required, or put it straight on the Web," says Klintz. The company has developed custom versions of the product for use with existing instruments.

It is also currently developing the hardware and software for a plug-in diagnostic module for a handheld PDA-type device.

To spread the word on wireless connectivity, Colorado MEDtech is sponsoring a series of seminars on the topic. At the one-day sessions, industry experts will report on the state of wireless technology, analyze existing connectivity standards, and share connectivity solutions. Speakers will include Colorado MEDtech senior vice president of product development and technology Bill Wood and Ray Jones, who is responsible for software programs, including embedded-software development. The seminars are scheduled to be held in San Francisco on October 23, San Diego on October 25, and Anaheim, CA on October 26.

From external to embedded solutions

Device Server Technology developed by Lantronix Inc. enables OEMs to connect devices to the Internet or other networks using standard protocols. The company's most recent product is DSTni, a single chip that contains all of the essential hardware components that allow devices to be remotely monitored or controlled over the Internet or shared networks. The chip's 12 x 12-mm ball-grid-array footprint makes it suitable for integration into the smallest devices. DSTni is designed for device OEMs seeking advanced integration, says technical marketing manager Paul Wacker, but the company offers a range of other options that achieve similar outcomes.

"We have found that OEMs first dip their toe in the water by going with our external solution, which connects a serial port to an Ethernet box," says Wacker. "That automatically puts a legacy device on-line." The company also produces a smaller version that is designed in the box, he adds. "From there we drop it down to the semiconductor level, where you're integrating more silicon into the motherboard. That's the typical migration path for most OEMs," notes Wacker.

DSTni comes with a suite of on-chip peripheral hardware to minimize integration risk and a 96-MHz processor. In addition to two 10/100 Ethernet MACs and an integrated physical layer, the chip has four high-speed serial ports, CANBUS, SP1, I2C, and parallel I/O. To ease installation, the company offers an OEM developer's kit that contains a reference design board and network-enabling software. Also included are a TCP/IP protocol stack to facilitate Ethernet connectivity, a set of C libraries and sample source code, and a Web server that enables standards-based graphical presentation, access, and control via any Web browser.

Norbert Sparrow

Copyright ©2001 Medical Product Manufacturing News