Analogue front end measures four common vital signs

This single-chip AFE from Analog Devices integrates three measurement systems (optical, ECG and bio-impedance) to obtain four common vital signs: electrocardiogram (ECG or EKG), heart rate (ECG or optical PPG), blood-oxygen saturation (SpO₂) and respiration rate (using BioZ).

The device enables synchronised optical PPG and ECG timing for derived health metrics. Medical device designers are eager to reduce annual healthcare-related expenditures by replacing office-based health monitoring systems with smaller, lower power, wireless devices worn discreetly and continuously in the home or office.

With three clinical-grade subsystems integrated into one IC, the MAX86178 triple system AFE replaces discrete implementations by integrating an optical PPG sub-system to measure heart rate and SpO₂, a single lead ECG sub-system, as well as a biopotential and bioimpedance (BioZ) sub-system to measure respiration rate.

It permits small vital signs devices by fitting those multiple functions into a 2.6mm x 2.8mm package. In addition, next-generation wearable RPMs need to operate at low power to permit smaller batteries or extend battery life to allow more convenient charging requirements.

To enable ultra-low power features, the device provides each subsystem with configurable options to optimise battery life for specific use cases. “By integrating three healthcare subsystems on one piece of silicon, Analog Devices builds on its DNA and delivers this sensor-fusion product,” said Andrew Burt, Executive Business Manager of the Industrial and Healthcare Business Unit at Maxim Integrated, now part of Analog Devices. “This AFE is resonating with the medical community because it presents new possibilities for chronic disease management, contagious disease diagnosis and remote monitoring. The MAX86178 enables small body-worn devices that can improve healthcare delivery and lower costs by keeping people out of the hospital.”

In addition, Analog Devices offers the MAX20343 buck-boost regulator and the MAX20360 power management IC as power solutions optimised for the MAX86178.

Benefits include its small size which enable it to replace medical facility grade monitoring systems with body-worn devices.

By integrating and synchronising three different measurement systems to measure four vital signs, it simplifies design and enables even more complicated derivative vital signs monitoring

Both the MAX86178 in a 2.6mm x 2.8mm WLP package and the MAX86178EVKIT are available now.