Customisable wireless medical sensor chip with machine learning accelerator enables mass market advanced medical and vital-sign monitors

EnSilica’s eSi-MediSense is the market’s only single chip medical sensor with wireless capability. Significantly brings down costs of wearable medical devices

July 15, 2020, Wokingham, UK – Ensilica, a leading provider of custom ASIC design and supply services, has created a customisable single-chip medical sensor ASIC platform to speed the development of wearable medical / fitness vital-sign monitoring products.

Called eSi-MediSense, it is the market’s only single chip medical sensor with wireless capability, and by being single chip, it brings costs down significantly: for example enabling a health monitoring watch to drop in cost from c.£250 to c.£100.

The ultra-low-power platform is able to work with multiple processor and DSP configurations and has an optional machine learning accelerator such as the Arm Ethos-U55 that enable artificial intelligence to be designed into medical sensors – both reducing the frequency of wireless communication and extending battery life.

The platform supports the accurate and reliable measurement of ECG, heart rate, respiration rate, pulse oximetry and temperature. A flexible interface is also provided for electro chemical-based measurement such as amperometric, voltammetric or impedance measurements.

Applications include recyclable smart plasters; physiotherapy monitors to track orthopaedic recovery, track abnormal heart conditions; or provide non-invasive glucose monitoring. By continuously monitoring expected vs unexpected activity, it is able to flag the need for medical assistance autonomously.

eSi-MediSense block diagram

After processing, data is encrypted and transmitted over either the 2.4 GHz ISM band radio (Wi-Fi / Bluetooth / proprietary and medical), a sub-1 GHz MBAN standard or an ultra low power standard such as BLE 5.0 or 802.15.4. An NFC-A tag can be integrated to simplify device pairing and enable medical sensor data to be read by a smartphone.

“The platform has been developed to work with a huge range of sensors: from ECG to temperature and from electro-chemical to bioimpedance. Plus, our design team have the expertise to develop and integrate additional custom sensor interfaces with demanding performance requirements.” said Ian Lankshear, CEO at EnSilica. ” It is an ideal platform to integrate custom sensors or run your smart diagnostic and remote healthcare applications on a single chip.”

Specifications

The eSi-MediSense is designed to conform to: IEC 60601-1, IEC 60601-2-27 and IEC60601-2-49.

The platform’s specialised medical analog front end is able to work with single lead and multi-lead ECG with clinical grade accuracy to enable R-R heart rate monitoring; temperature sensor interfaces to ISO 80601-2-56; bioimpedance channel capable of measuring respiration; and multi-channel electrochemical impedance spectroscopy (EIS).

It is able to support voltages between 1.0 and 3.6 V and its multiple power states are able to deliver a standby current of <1 µA. Data is encrypted on the chip using crypto accelerators: AES-256, SHA-512 and ECC-384 with a true-random number generator (NIST 800-22). And the platform is able to use a range of real time operating systems, including FreeRTOS, SafeRTOS, ThreadX and eBed OS, and comes with a feature rich DSP software library for easy algorithm programming. The eSi-MediSense platform comes in Low-pin count QFN or B/LGA packaging options or a bare die for flip-chip bumping directly onto the PCB. For further information you can download a datasheet from the EnSilica website - https://www.ensilica.com/market-sectors/medical-asic/