Philipp Schilk, ETHZ D-ITET PBL 2022-2024
A Self-contained, Miniaturized, BLE-enabled Embedded Platform for Low-Power, Wearable, and Hearable Applications.
Pictures: Frank K. Gürkaynak, 2022
- 03/04/2024: First public release (Hardware v1.3)
The VitalCore is a highly integrated, miniaturized embedded systems platform that features everything a low-power wearable project usually requires - except for application specific sensors and transducers. Its small 17.6 mm ** 12.6 mm size allows it to be integrated even in the most constraint applications, include in-ear/hearable projects. Based around an NRF5340 SoC, the VitalCore features a dual-core Cortex-M33 processor running at up to 128 MHz, 1 MB of Flash, 512 KB RAM, and BLE 5.2 complete with an on-board chip antenna.
On its back, the VitalCore features a 0.4 mm pitch 50-position connector that can be used to attach application-specific 'VitalPack' expansion boards. This connector exposes power inputs and outputs, the SoC's programming interface and USB port, and 28 GPIO pins with ADC, I2C, SPI, I2S, UART, QSPI, and PDM interfaces available. The SWD pin, battery and charger connections, and QVAR inputs are also available as SMD solder pads on the back side.
The exact pinout is specified in the full documentation pdf.
To accommodate different stacking heights, the following combinations of header (on the VitalCore) and receptacles (on the VitalPack) can be used:
| Stacking Height | Header | Receptacle |
|---|---|---|
| 0.7mm | JAE Electronics WP7B-P050VA1-R8000 | JAE Electronics WP7B-S050VA1-R8000 |
| 1.5mm | Hirose DF40C-50DP-0.4V(51) | Hirose DF40C-50DS-0.4V(51) |
| 2.0mm | Hirose DF40C-2.0-50DP-0.4V(51) | Hirose DF40C-2.0-50DS-0.4V(51) |
| 2.5mm | Hirose DF40C-2.5-50DP-0.4V(51) | Hirose DF40C-2.5-50DS-0.4V(51) |
A MAX77654 PMIC provides a full power subsystem, including a software-controlled battery charger with power path switching and up to 300 mA charge current, a battery monitor, 3 software-controllable switch mode buck-boost converters each with an output range of 0.8 V to 5.5 V, and two software-controlled LDOs each with an output range of 1.71 V to 5.3 V. All on-board devices (SoC and peripherals) are powered using a dedicated 1.8 V buck converter, making all SMPS and LDO outputs available application-specific circuitry via the VitalPack connector.
The VitalCore comes equipped with the following peripherals:
- A high-performance LSM6DSV16BX IMU with accelerometer, gyroscope and QVAR frontend.
- A 256Mb W25Q256JWYIM QSPI Flash.
- An RGB LED and IS31FL3194 driver capable of LED animations/patterns.
The VitalCore Altium project/gerber files include a panel to be used during development. It exposes the NRF's SWD programming interface, USB port, power inputs, and power rail test points. It can be removed manually by cutting the small PCB bridges, or be excluded before production entirely.
Important
Device sheet folder must be configured correctly in Altium for project to be opened correctly.
This project uses device sheets to for common building blocks (in VC_Common) that
are used in other projects. The folder VC_Common/DevSheets must be added to Altium's
list of device sheet locations! See below:
https://www.altium.com/documentation/altium-designer/device-sheets
To avoid annotation collision between components in device sheets and components within each project, all device sheet components are annotated with a 'D' Suffix. Altium should be able to handle this via 'Board Level Annotation', but it has been rather buggy.
Any modifications to device sheets don't seem to propagate to projects using those sheets until those projects are closed & re-opened, or Altium is restarted.
Will follow shortly
Will follow shortly
Examples of VitalCore-based projects:
In-Ear Hand Gesture Recognition with Ultra-Low Power mmWave Radars.
A Low Power In-Ear Vital Parameter Monitoring System
Towards Milli-Watt Audio Enhancement With Bone-Conduction Microphones for In-Ear Sensing Platforms
Published under the GNU GPLv3 license.
If you find VitalCore useful, we would appreciate if you cite one of the following papers:
@inproceedings{TinyssimoRadar,
author={Ronco, Andrea and Schilk, Philipp and Magno, Michele},
booktitle={2024 IEEE/ACM Ninth International Conference on Internet-of-Things Design and Implementation (IoTDI)},
title={TinyssimoRadar: In-Ear Hand Gesture Recognition with Ultra-Low Power mmWave Radars},
year={2024},
volume={},
number={},
pages={192-202},
doi={10.1109/IoTDI61053.2024.00021}
}@inproceedings{InEarVoice,
author = {Schilk, Philipp and Polvani, Niccol\`{o} and Ronco, Andrea and Cernak, Milos and Magno, Michele},
booktitle = {Proceedings of the 8th ACM/IEEE Conference on Internet of Things Design and Implementation},
title = {In-Ear-Voice: Towards Milli-Watt Audio Enhancement With Bone-Conduction Microphones for In-Ear Sensing Platforms},
year = {2023},
isbn = {9798400700378},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {https://doi.org/10.1145/3576842.3582365},
doi = {10.1145/3576842.3582365},
pages = {1–12},
numpages = {12},
series = {IoTDI '23}
}@inproceedings{VitalPod,
author={Schilk, Philipp and Dheman, Kanika and Magno, Michele},
booktitle={2022 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob)},
title={VitalPod: A Low Power In-Ear Vital Parameter Monitoring System},
year={2022},
volume={},
number={},
pages={94-99},
doi={10.1109/WiMob55322.2022.9941646}
}