8 layers42.2 × 67.2 mm
OBC PCB
timohueser/OpenBikeComputer
Open source Bikecomputer with a focus on exploration and adventure.
186 parts11GPL-3.0
2 layers
Smartwatch
alexew0923/SmartwatchA custom smartwatch built with 1.28 inch round TFT touchscreen display and ESP32
- Copper layers
- 2
- Thickness
- 1.6 mm
- Parts
- 25
- Nets
- 31
- Pads
- 102
- Tracks, vias
- 243, 28
- Routed
- Yes
- KiCad
- KiCad 10.0 (file 20260206)
- Created
- 25 Jun 2026
- Updated
- 5 Nov 2026
Overview
Smartwatch is an open-source printed circuit board by alexew0923, from the alexew0923/Smartwatch repository on GitHub. It is a 2-layer board with 25 parts on 31 nets, routed with 243 tracks and 28 vias.
It is built around the BMP581, VEML6035 and CPT-9019A-SMT-TR, with the DS3231S# among its other parts. Its parts include 10 resistors, 6 ICs, 4 capacitors, 2 connectors and 2 switches. It belongs with the wearables boards and the ESP32 and RISC-V boards of this library.
Main components
4
BMP581
LGA-10(2x2)-40℃~+85℃ 0.5pa/K 1.71V~3.6V 1uA 30Kpa~1.25bar 6pa I2C、SPI、I3C LGA-10(2x2) Pressure Sensors ROHSBosch SensortecPressure SensorsVEML6035
SMD-6P-25℃~+85℃ 0.4mm 1.7V~3.6V 16bit 170uA 2mm 2mm 6.71klx I2C Light Intensity SMD-6P Ambient Light Sensors ROHSVishay IntertechnologyAmbient Light Sensors
CPT-9019A-SMT-TR
SMD,9x9mm-40℃~+85℃ 0V~25V 1.9mm 1mA 3V 4kHz 75dB 9mm 9mm Passive (Externally Driven) Piezoelectric SMD SMD,9x9mm Buzzers ROHSCUIBuzzers
DS3231S#
RTC, I²C, ±3.5ppm, SOIC16Maxim Integrated (Analog Devices)Uncategorised
README
README.mdSmartch
This repository contains all the files for the smartwatch and it is participating in the Stardance Challenge by Hack Club.
Demo Video
Bill of Materials
Components are bought from DigiKey, AliExpress and Amazon. For more information, refer to the excel file under KiCad.
- XIAO ESP32C3 (main processor)
- 450mAh LiPo Battery with PH 2.0 mm JST Connector
- PH 2.0 mm JST Connector
- 4 x 100nF 0603_1608 Capacitors (DigiKey part number: 1276-1005-1-ND)
- 1.28 inch Round TFT Display (with pin sockets)
- DS3231 RTC Module (with pin headers)
- 6 x 10k 0603_1608 Resistors (DigiKey part number: 311-10.0KHRCT-ND)
- 4 x 4.7k 0603_1608 Resistors (DigiKey part number: 311-4.70KHRCT-ND)
- 2 x Tactile Switches (DigiKey part number: P10851SCT-ND)
- SMD SHT40 Temp&Hum Sensor (DigiKey part number: 1649-SHT40-AD1F-R2CT-ND)
- SMD VEML6035 Ambient Light Sensor (DigiKey part number: VEML6035CT-ND)
- MPU6050 (with pin sockets)
- SMD BMP581 Air Pressure Sensor (DigiKey part number: 828-BMP581CT-ND)
- SMD CPT-9019A-SMT-TR Passive Buzzer (DigiKey part number: 2223-CPT-9019A-SMT-TRCT-ND)
The total cost is 49.45 CAD.
KiCad Designs
Schematic
PCB
I used JLCPCB, but you can you any other PCB fabrication services. I selected 1.6 mm white PCB. If want to solder components by yourself rather than assembly option, order a stencil and solder paste as well. When soldering the battery connector, double check the polarity! There are schematic and PCB file under KiCad, so feel free to modify it or if you would like to order it right away, download Smartwatch.zip file which contains gerber files and upload it onto PCB manufacture's website.
Case Design
I 3D printed a case designed on SolidWorks. The PCB sits on the base of the case and the lid snaps into the body. When you are modifying the SolidWorks file, be careful because I am using a student version, so it will leave a watermark. If you would like to 3D print it, you can use the STL file instead.
Core Feature
This smartwatch uses LVGL graphics library to develop user interface.
Current Features
- Uses DS3231 RTC module, keeping time reliably even when the battery is dead.
- Basic features in a clock app, such as stopwatch, timer and time adjustment.
- Uses SHT40 sensor to log temperature on a graph.
- Accelerometer & gyroscope readings and visualization using MPU6050.
- Air pressure and altitude readings from BMP581.
Features for Future Version
- Connect to the phone via Bluetooth to receive data such as weather, message, and news.
- Battery voltage reading
Parts
25| Qty | Value | Footprint | References |
|---|---|---|---|
| 6 | 10k | Resistor_SMD:R_0603_1608Metric | R1, R2, R7, R8, R9, R10 |
| 4 | 100nF | Capacitor_SMD:C_0603_1608Metric | C1, C2, C3, C4 |
| 4 | 4.7k | Resistor_SMD:R_0603_1608Metric | R3, R4, R5, R6 |
| 2 | SW_Push | Button_Switch_SMD:Panasonic_EVQPUJ_EVQPUA | SW1, SW2 |
| 1 | BMP581 | MPU581:QFN10_BMP581_BOS | U5 |
| 1 | Battery | Connector_JST:JST_PH_S2B-PH-K_1x02_P2.00mm_Horizontal | BT1 |
| 1 | CPT-9019A-SMT-TR | XDCR_CPT-9019A-SMT-TR Passive Buzzer:XDCR_CPT-9019A-SMT-TR | U6 |
| 1 | DS3231 | Connector_PinHeader_2.54mm:PinHeader_1x05_P2.54mm_Vertical | J2 |
| 1 | OC09600 | MPU6050:MODULE_OC09600 | U4 |
| 1 | SHT4x | Sensor_Humidity:Sensirion_DFN-4_1.5x1.5mm_P0.8mm_SHT4x_NoCentralPad | U2 |
| 1 | TFT Round Display | Connector_PinSocket_2.54mm:PinSocket_1x07_P2.54mm_Vertical | J1 |
| 1 | VEML6035 | VEML6035:XDCR_VEML6035 | U3 |
| 1 | XIAO-ESP32-C3-SMD | Seeed_Studio_XIAO_Series:XIAO-ESP32-C3-SMD | U1 |
Similar boards
- 4 layers55 × 28 mm
Sensor node
UPM-SPV/pcb
Coin-cell powered BLE weather station with nRF54L15. Measuring temperature, humidity, air quality, luminosity, and noise.
72 partsCERN-OHL-S-2.0 - 4 layers66 × 32.4 mm
- 2 layers50.2 × 95.2 mm
- 4 layers72 × 55 mm
Exhaust mic
HasiKe/Exhaust-Mic
Motorcycle Exhaust and Intake Microphone for best soud on Videos.
135 parts - 6 layers30 × 60 mm
LSR FLCM0001 A03
Louisiana-State-Rocketry/FLCM0001-A03_PCB
PCB Files for the Eclipse 2 Flight Computer.
150 partsMIT - 4 layers
- 4 layers41.1 × 96.6 mm
Questions
What parts does the Smartwatch use?
25 parts, built around the BMP581, VEML6035, CPT-9019A-SMT-TR and DS3231S#. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
Where can I download the Smartwatch KiCad files?
From the alexew0923/Smartwatch repository on GitHub, at the commit this page was made from: the board is KiCad/Smartwatch.kicad_pcb and its schematic KiCad/Smartwatch.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Can I use the Smartwatch design in my own project?
Its repository states no licence, so its author keeps all rights: ask alexew0923 before reusing the design.