(Editor's note: This paper from Microsemi Corp. is obviously somewhat "biased" towards their products and technical approaches, of course. But it also contains some useful insight and information which makes it worthwhile for all device designs at this level.)
With the trend towards miniaturization comes the requirement for improved security to maintain patient confidentiality. Reliability is also a requirement, both in terms of product longevity and assurance that the device is working as specified. This is crucial for the rapidly expanding market for devices used in emergency interventions.
For instance, an automated external defibrillator must be safe to use. At the same time, paramedics and other trained personnel need assurance that the device is working properly—that it will deliver the precise electric shock required and will not discharge inappropriately. Similarly, designers must assure performance, reliability, safety, and security for devices such as a portable insulin pump, see Figure 1.
Figure 1: Portable insulin pump block diagram, showing functions that can be implemented by Microsemi FPGAs
Typically, designers of portable medical applications have relied on microcontrollers, application-specific standard product (ASSP) chips and small programmable logic devices to glue them together in order to build human-machine interface (HMI) and miniature motor controllers. These combinations are less than ideal with the demand to miniaturize equipment, while not compromising on channel count for critical sensors and actuators.
A solution based on field-programmable gate arrays (FPGAs) makes it easier to fit more functionality into less space. ASSPs do not provide design flexibility or the ability to upgrade functions after manufacture. If the design needs to change to reflect new standards or to upgrade functionality, Microsemi's flash-based FPGAs can be reprogrammed in the field and have security mechanisms built in to ensure that only legitimate upgrades can be applied to equipment.
To read the entire paper, click here.