Updated on 17 September 2013
Vital signs are currently being monitored across market sectors with a common set of requirements, but environmental constraints and how the information is interpreted and used has significant impact on the efficacy of any monitoring device. Analog Devices is the technology leader bringing innovative responses to address these constraints. Following are a few of the market subsets and goals, constraints, and proposed technologies that will enable the desired personal health monitoring capabilities.
Devices must be non-intrusive and fit seamlessly with our lifestyle- a requirement that resonates across all market sectors. Devices must be small, and since most will likely be body worn, they will need to be battery operated (either disposable or rechargeable). The user does not want to be fiddling with batteries or chargers frequently, so the devices must support ultra-low power consumption to provide uninterrupted, long term use.
Home health monitoring falls into three categories: disease management, health and wellness and safety. Disease management includes glucose measurement, cardiac monitoring, pulse oximetry, continuous blood pressure, and respiration monitoring. It is expected that these devices will be prescribed following a clinical consultation. The device will require a certain level of regulatory approval (like FDA), and the compliance requirements will be as high as for those devices intended for hospital environment. In addition, the devices will need to be small, portable, ultra-low power, and wirelessly connected. Products like Analog Devices' ADAS1000-3, a single chip 3-lead ECG analog front end (AFE) provide diagnostic-quality signals to ensure regulatory compliance and support the home health prerequisites of small size, portability, and low power.
Fall detectors are one of the most common devices currently deployed amongst the aging population giving them the flexibility to continue to stay independently while ensuring help is on instant reach. Although these devices do not prevent a fall, they provide a remote alarm that alerts family members or authorities of an adverse event. The key requirements of these devices are low power, small construction, and wireless connectivity. They must also be able to discern between a person sitting down quickly and an actual fall. Extended battery life is critical because changing a battery may require a caregiver visit or a third-party visit at an additional cost to the wearer. A dead battery means a monitor is no longer active, putting the wearer at additional risk. Fall detectors use low-g MEMS accelerometers to detect and distinguish type of motion.
Analog Devices ADXL362 is the industry's lowest power, 3-axis MEMS accelerometer. With an operating current of 1.8 μA @ 100 Hz operating data rate (ODR), 3 μA @ 400 Hz ODR, only 270 nA when in motion activated wake-up mode, and 10 nA standby current, the ADXL362 can extend the battery life of a fall detector by many months.