Maxim Unveils HSP 3.0 Reference Wearable Design
HSP 3.0 with free source code access
Collection of medical data such as HR, ECG, HRV, and SpO2


The COVID-19 pandemic has made remote monitoring of patients' vital signs more important than ever. The pandemic is accelerating the adoption of digital healthcare services, which had previously been sluggish. Remote monitoring is expected to play a crucial role in preventive medicine and chronic disease management.

Maxim Integrated Korea released the 'Health Sensor Platform (HSP) 3.0' on the 12th, which can shorten the development time of healthcare wearable devices by more than six months.

Today, many healthcare professionals and users are using wearable devices to obtain health information and manage chronic and acute conditions. As demand for more health information and accurate analysis grows, wearable device manufacturers are incorporating multiple measurement technologies into their devices.

Maxim's wristwatch-type reference wearable device, 'MAXREFDES104#', provides medical-grade information on body temperature, activity, respiratory rate (RR), heart rate (HR), electrocardiogram (ECG), heart rate variability (HRV), blood oxygen saturation (SpO2), as well as sleep quality and stress index through built-in algorithms.

Wearable designers can immediately begin collecting data with this reference product, reducing device development time by more than six months.

Unlike HSP 2.0, which was released in 2018, HSP 3.0 can measure ECG, SpO2, and use dry electrodes, so it can be made into a patch or ring-type wearable device to detect heart and respiratory problems, and can manage diseases such as chronic obstructive pulmonary disease (COPD), infectious diseases (COVID-19), and obstructive sleep apnea (AFiB).

With freely available source code and design files, HSP 3.0 also includes complete optical and electrode designs, along with algorithms to meet medical requirements. To achieve this, HSP 3.0 utilizes improved devices compared to those featured in HSP 2.0.

◇ Five Maxim devices used in HSP 3.0

The MAX86176 analog front end (AFE) performs photoplethysmography (PPG) and electrocardiography (ECG) measurements, providing a signal-to-noise ratio (SNR) of 110dB and a common-mode rejection ratio (CMRR) of greater than 110dB for oxygen saturation for dry electrode ECG applications. Synchronous acquisition of PPG and ECG measurements at independent sampling rates provides pulse transit time information relevant to cardiac disease.

Optimized for wearable health monitoring devices, the MAX20360 PMIC consists of Maxim's ModelGauge m5 EZ battery fuel gauge module and a sophisticated haptic driver, along with a low-noise buck-boost converter driver that maximizes SNR and minimizes power used for optical biosensing.

The ultra-low-power MAX32666 MCU with built-in Bluetooth features dual Arm Cortex-M4F cores and a smart DMA. The smart DMA allows the BLE stack to run independently, freeing the two main cores for critical tasks. Furthermore, all security features and error-correcting code (ECC) are integrated into memory, enhancing system reliability.

The 'MAX32670', an ultra-low-power MCU for PPG algorithms, can be configured as a sensor hub that supports firmware and algorithms or an algorithm hub that supports multiple algorithms. Additionally, it seamlessly implements customer-desired sensor functions, such as managing the MAX86176 PPG and ECG measurement AFE and providing raw or output data to external parties.

The MAX30208 digital temperature sensor, featuring low power consumption and high accuracy, is housed in an ultra-small 2mm x 2mm package. It measures temperature from the top of the package and can be mounted on a flexible cable or PCB, making it ideal for wearable product design. With a 0.1°C error range, it also meets medical-grade temperature requirements.