Nordic Semiconductor nRF52840
Industrial Worker Health Smart Band
Overview
A wearable BLE sensor node designed as a smart band for industrial worker safety, monitoring heart rate and body temperature with a 3-7 day battery life.
Jiaze KeSystem architecture
MCU
SENSOR
POWER
- MCU → SENSOR_PPGI2CI2C bus for PPG configuration and data reading, plus interrupt line
- MCU → SENSOR_TEMPI2CI2C bus for high-accuracy temperature readings
- MCU → SENSOR_IMUI2CI2C bus and interrupt for motion tracking and gesture detection
- POWER → MCUPowerProvides regulated 3.3V supply to the MCU
- POWER → SENSOR_PPGPowerProvides regulated power rails to the optical AFE
- POWER → SENSOR_TEMPPowerProvides regulated 3.3V supply to temperature sensor
- POWER → SENSOR_IMUPowerProvides regulated 3.3V supply to IMU
Bill of materials
| Part number | Type | Component | Manufacturer | Package | Qty | Datasheet | Match |
|---|---|---|---|---|---|---|---|
| NRF52840-DK | MCU | Nordic Semiconductor nRF52840 Core processing unit and BLE 5.2 wireless communication | Nordic Semiconductor ASA | — | 1 | Matched | |
| MAX30101EFD+ | SENSOR | Analog Devices MAX30101 Optical heart rate and SpO2 monitoring | Maxim Integrated Products, Inc. | — | 1 | Matched | |
| TMP117AIDRVR | SENSOR | Texas Instruments TMP117 High-accuracy body temperature monitoring | Texas Instruments | WSON-6 | 1 | Matched | |
| BMI270 | SENSOR | Bosch Sensortec BMI270 Motion tracking, step counting, and gesture wake-up | Bosch Sensortec GmbH | LGA-14 | 1 | Matched | |
| T/ | POWER | Nordic Semiconductor nPM1300 Li-Ion battery charging and power management | Industrial Seating Inc. | — | 1 | Matched |
Build guide
6-8 hoursAdvanced
1
Procurement & Preparation
- Procure and inventory all core electronic components: Nordic nRF52840 development board, Analog Devices MAX30101EFD+ optical sensor, Texas Instruments TMP117AIDRVR temperature sensor, Bosch Sensortec BMI270 IMU, and Nordic nPM1300 power management IC.
- Prepare the printed circuit board (PCB) stencil, lead-free SAC305 solder paste, and clean the work surface with isopropyl alcohol.
2
Hardware Assembly & Wiring
- Apply lead-free solder paste to the PCB pads using the stainless steel stencil and alignment jig.
- Place the Nordic nRF52840 MCU, MAX30101 optical sensor, TMP117 temperature sensor, BMI270 IMU, and nPM1300 PMIC onto their respective designated SMT pads.
- Execute reflow soldering profile adhering to SAC305 thermal specifications (peak temperature 245 degrees Celsius).
- Establish power and I2C signal interconnects: wire VCC_3V3, VCC_1V8, GND, SDA, SCL, and INT lines between the nRF52840 MCU, MAX30101, TMP117, BMI270, and nPM1300 power management system.
3
Firmware Setup
- Install Nordic nRF Connect SDK, SEGGER Embedded Studio, and configure the toolchain for the nRF52840 core processing unit.
- Compile and flash the firmware image incorporating drivers for the MAX30101 PPG sensor, TMP117 temperature sensor, BMI270 IMU, and nPM1300 power management IC.
4
Testing & Calibration
- Verify quiescent current consumption and battery charging functionality via the nPM1300 to ensure 3-7 day operational battery life.
- Calibrate the TMP117 body temperature sensor against a certified reference thermometer and test optical heart rate response on the MAX30101.
- Perform Bluetooth 5.2 wireless connection range and packet integrity tests, alongside BMI270 motion tracking and gesture wake-up verification.
Document
BLE health monitoring smart band
A wearable BLE sensor node designed as a smart band for industrial worker safety, monitoring heart rate and body temperature with a 3-7 day battery life.
Design Overview
| Item | Details |
|---|---|
| Product Type | BLE health monitoring smart band |
| Key Functions | Monitor heart rate, Monitor body temperature, BLE wireless data transmission, Rechargeable battery power management |
| Power Source | Li-Ion Battery |
| Connectivity | Bluetooth |
| Size | Wristwatch or smart band form factor |
| Environment | wearable |
| Difficulty | Advanced |
| Est. Time | 6-8 hours |
System Architecture
Power Topology: Li-Ion battery connected to the nPM1300 PMIC input/charger. The PMIC provides a regulated 3.3V main rail for the nRF52840 MCU, sensors (TMP117, BMI270), and sub-regulated rails (e.g. 1.8V/3.3V) for the MAX30101 optical AFE.
Module List
| Module ID | Type | Name | Function | Voltage |
|---|---|---|---|---|
| MCU | MCU | Nordic Semiconductor nRF52840 | Core processing unit and BLE 5.2 wireless communication | 3.3V |
| SENSOR_PPG | SENSOR | Analog Devices MAX30101 | Optical heart rate and SpO2 monitoring | 1.8V / 3.3V |
| SENSOR_TEMP | SENSOR | Texas Instruments TMP117 | High-accuracy body temperature monitoring | 3.3V |
| SENSOR_IMU | SENSOR | Bosch Sensortec BMI270 | Motion tracking, step counting, and gesture wake-up | 3.3V |
| POWER | POWER | Nordic Semiconductor nPM1300 | Li-Ion battery charging and power management | 3.7V (Battery) / 3.3V |
Key Components
5/5 modules matched to real parts. See the BOM tab for the full component table.
Nordic Semiconductor nRF52840 (NRF52840-DK)
The NRF52840-DK is the standard, official development kit for the Nordic Semiconductor nRF52840 module, making it the mo
Nordic Semiconductor nPM1300 (T/)
None of the provided candidates match the searched part 'MAX77654EFWP+T' (Maxim Integrated power management IC). All can
Build Summary
- Difficulty: Advanced
- Estimated time: 6-8 hours
- Tools required: Antistatic tweezers, Component storage bins, Digital microscope, PCB stencil, Squeegee, Isopropyl alcohol 99%
See the Build tab for the full step-by-step assembly guide.
Generated by YuanQi AI Design System · Query: design a ble sensor node for monitor heart beat rate and body temperature