Part 1 of this report discussed the concept that the continued drive toward smaller form factors may not always be necessary or better. This extensive debate led to the conclusion that right-sizing is the new mantra. Now, the discussion turns to a few selected approaches, methods, techniques, and technologies that will allow right-sizing of the electronics elements in products.

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Right-Sizing Techniques and Technologies

Electronics are permeating many medical devices that, to date, have been strictly mechanical in function. Integrating electronics allows the addition of functions and features such as imaging, sensing, and monitoring to previously functionally passive devices. Until now tasked with only moving fluids or materials, these devices are now empowered to move data. Electronics integration allows the communication of data from devices that previously were not connected. This allows precise control over the main function of the device, such as drug delivery.

One example is medication compliancy from sensors embedded into delivery devices or directly into the medication. In this digital, connected world, where we will be focused and paid on patient outcomes, data is becoming the critical element in measuring, judging and proving the efficacy of whether a particular treatment is positively affecting behavior and ultimately health outcomes of an individual or a population.

During the design and development phase, more time must be spent in evaluating the current supply chain for available well-priced and proven technologies. In many cases, using standard cost-effective "good enough" or conventional components and technologies combined with highly creative design and assembly skills can result in a better, cost-effective, right-sized form factor for the function and environment.

There are many approaches to selecting right-sized technologies for many application situations. First, there is a need to balance the selection of the technology based on need, end-user requirements, costs, technology maturity, and a weighted appetite for technical risks. The selected technology must not only be the right fit but it also must have the right timing to ensure both short-term availability and standardization for clinical trials and the launch phase as well as long-term support for the entire product life.

Deploying a strategy where effort and time by the designers and supply-chain team must be spent on evaluation of the current supply chain for available well-priced and proven technologies can be a differentiating factor in bringing new right-sized devices to market. In many cases, using standard cost effective "good enough" or conventional components and technologies, combined with creative design and assembly skills .can result in a cost effective, right-sized form factor for the function and environment that easily meets comparative effectiveness and cost targets.

Physical Size Reduction

This is the oft-treaded evolutionary path that drives technologists to continue to develop new designs, materials, components, and manufacturing solutions. Altering and reducing the physical form of the device can prove to be one way to gain new strides in patient outcomes. The following plethora of technologies ranges from the obvious to quite creative.

The move to smaller-size packaged components, such as 0201 to 01005, using super-thin capacitor (Figure 1), stacked packages (Figure 2), or wire-bonded dies in cavity, might be obvious but is actually quite challenging from a cost, availability, and reliability perspective. While these components have been incorporated into a variety of consumer and niche medical devices, making their assembly understood from a production perspective, widespread adoption across the rest of the product landscape is slow in coming.

Another area of focus for right-sizing medical devices is embedding active and passive components into substrates, whereby the components are being incorporated as part of the PCB layers during PCB fabrication (Figure 3). Over the years, this technology has been increasingly used to create modules by utilizing passive components that are embedded or placed within the PCB during the fabrication process. Significant upfront design is required for modeling electrical values within manufacturing tolerances. Because it is almost impossible to rework the active and passive embedded components once the PCB lot has been fabricated, accurate production forecasting over the life of the product is required. The reliability impact of increasing embedded content within the PCB is an additional critical factor. The entire supplier ecosystem must develop expertise and production maturity in materials, design, manufacturing, testing, and failure analysis. In addition, recycling of the embedded content would be difficult. While not insurmountable, these challenges need to be considered before the technology can be widely adopted.

There are also several other proven and emerging approaches that allow designers to reduce the size of the product through reduction in physical dimensions including thinner substrates or dies, finer circuit traces and lines, novel interconnections for stacking dies such as TSV (Through Silicon Vias), printed electronics, micro-fluidics technologies including low-cost trenched substrates like plastics instead of extruded or machine metal tubes, and the substitution of wire bonds with printed traces.

Electrical Densification: Packing more electrical power and functionality into the same physical space to allow for increased efficiency or functionality is another design option that can be employed for right-sizing.

Functional Integration: The ability to integrate functional features into passive products can eliminate additional packaging. Integration can also be achieved by proliferating the niche use of molded interconnect technology. Instead of using separate components for electronics (PCB or flex) and plastics, interconnection traces are created directly on the plastic body. Components are then placed in the three-dimensional space. Another emerging option is to use 3D printing to create these electrical structures on plastic surfaces. Using a combination of metal and plastic additive manufacturing, these structures could potentially be created seamlessly on single platforms in the future.

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This file type includes high resolution graphics and schematics when applicable.