Miniaturization, reliability, cost & performance - accept no compromise
Developments within the field of medical electronics are focused heavily on miniaturization and reliability. Size matters because of complexity, and the trend towards portability and even wearability. Reliability is an obvious requirement, but one which is harder to guarantee if equipment is being used by patients remotely in their own homes or where electrical interference may be experienced. Interconnection has been thought of – sometimes literally – as the weak link, but it need not be that way, as long as the correct system is chosen.
Demand from hospitals, doctors and an increasingly-educated public for more function and increased portability has driven the improvement of surgical, diagnosis and monitoring equipment. A second trend is resulting in shorter hospital stays, to free up hospital beds and also as research shows that patients can recover more quickly at home after necessary hospital treatment. Therefore one can find greater use of technology in doctors’ surgeries, neighborhood radiology examination offices and outpatient clinics where patient clients are offered services varying from blood analysis and endoscope related procedures to minimally invasive ultrasound procedures in smaller localized facilities. The new-generation equipment often requires data-intensive imaging and probes or sensors that directly contact the patient and may be exposed to corrosive fluids.
As a result of this move towards a more dynamic medical service system, there is an ongoing demand for smaller, more portable, more capable equipment that can serve both practitioner and patient better and at a lower cost. To achieve this reliably, every portion of the equipment design must be considered carefully. Connectors and interconnect systems exist to serve every application. However, connectors that are fit-for-purpose in cost-conscious consumer goods with a limited life, or used in equipment that operates only in benign conditions will not suit demanding applications. Neither will they necessarily be small enough for the latest medical applications nor capable of operating securely in an electrically noisy environment. On the other hand, traditional ‘hi-rel’ connectors are often bulky and cannot always handle the high density, high signal speeds that increasingly are required by advanced medical systems – certainly they will be too expensive for many medical applications.
It appears that a gap is opening up between cheap and small but relatively limited performance connector systems and highly reliable military-style devices that are, however, bulky and expensive. However, this is set to change with recent developments to the Datamate family of hi-rel connectors manufactured by Harwin.
Harwin is a manufacturer of standard interconnect components with an enviable reputation for high quality and customer service. Its high reliability Datamate range, a 2mm pitch cable to cable, cable to board and board to board connector family, has been specified for use in harsh operating conditions many times, featuring on the Robonaut 2 NASA space robotics program, missile guidance and roadside bomb detection systems, UAVs, auto sport telemetry systems, dialysis and patient monitoring equipment. Datamate’s patented contact design features a stamped, four-fingered, gold-plated beryllium copper clip with highly stressed contact beams. The clips reside in the female half of the connector clasping round pins tightly, ensuring the integrity of electrical connection even under severe conditions.
Now Harwin has extended Datamate to include miniature, lightweight mixed technology versions. Datamate Mix-Tek range offers a multitude of configurations for signal, power and/or coax, effectively allowing the customer to configure their own Datamate connector, specific to their application, by mixing and matching the required signal, power and/or coax contacts up to a maximum of 50 low frequency contacts or 12 special (coax and power) contacts. Miniature Mix-Tek connectors feature power contacts rated for use at up to 20 amps. Signal contacts are rated at up to 3 amps; coax contacts are rated at 50 ohms.
Connectors are optionally available with quick-mate 101lok or jackscrew terminations for added security in applications which require extra contact security. They are available in Male PC Tail, Female Crimp, Male Crimp and Female PC Tail options. Housings are polarized and have a UL94V-0 rating. Mix-Tek connectors comply with the international standards CECC 75101-008.
Addressing signal speed, Harwin has just submitted Datamate for independent testing which confirmed that the connector family performs well enough at high speed to make it suitable for many USB 2.0 designs – although marginally outside the spec. These results open up a whole new range of markets for Datamate – and potentially for USB 2.0. Whereas previously if designers had wanted a hi-rel USB 2.0 connection they would have needed to tool special fixtures or housings and maybe select a custom connector, now (in most instances) they can use the appropriate Datamate device – potentially even running power, fibre optic or coax signals through the same device – while guaranteeing secure data transmission in the most extreme of operating conditions.
In a further development, Harwin has developed single-piece, machined metal backshells for the Datamate range to provide electrical screening against RFI and EMI interference. Datamate Metal Backshells give industry’s lowest cost, shielded hi-rel connector, and its launch means that Datamate, well-proven in harsh environments, can now be considered for I/O applications as well as PCB-mount designs.
Manufactured in aluminium alloy and nickel plated for electrical performance and corrosion resistance, when used in conjunction with the relevant Datamate J-Tek connectors and metal braid, Datamate metal backshells ensure full 360 degree electrical shielding. Designed to attach to a wide variety of standard metallic braids using industry standard tools, the backshells enable the shield braid to be connected through the backshell to the PCB ground plane. Available in female cable-to-PCB-mount and female cable-to-panel-mount configurations in a range of sizes including 6, 10, 14, 20 and 26 positions, the backshells also provide excellent design flexibility. Delivering 55/125/56 (-55 to +125°C, 56 day damp heat steady state) performance levels, the new backshells are mechanically strong and easily assembled using industry standard tooling. The Datamate J-Tek connectors also feature jackscrews for added mating security.
This combination of screening, security and performance means that Datamate connectors and backshells will suit many applications in the medical market where electrical noise is, or may be, present.
Various different Datamate connectors are already being used by manufacturers of medical equipment in applications from blood pressure monitoring to imaging and on to micro-surgery to reduce size and cost without compromising performance and reliability.