DIY Leta - Wrist watch using Stm32f103

Description

The name Leta(summer in Russian) is started from my summer when i saw guys made wrist watch with atmel MCU, and another with chinese MCU. I decided to make my own, with the hope that i can gain some in embedded field. It took me about one year to almost complete this, althought there still some bugs. Those links to my project in github profile include this project, my mini RTOS ( AK-mOS) and my monochrome Oled GUI.

Files

myWatch.step

3d model for my watch

step - 4.57 MB - 12/31/2024 at 20:54

Download

Sheet1.pdf

Adobe Portable Document Format - 428.93 kB - 12/31/2024 at 20:54

Preview

To_Manufactor.zip

x-zip-compressed - 205.24 kB - 12/31/2024 at 20:54

Download

Components

1 × MPU6050 - IMU

1 × HCM5883L - Compass

1 × AHT21 - Temp and humid

1 × BLE - RF-BM-4044B4 from RF-star Technology

1 × Stm32f103 Microprocessors, Microcontrollers, DSPs / Microcontrollers (MCUs)

Build Instructions

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1

Schematic

The schematic is quite simple. When i started making this watch, i didnt think that much about power saving. So i made auto-shutdown circuit, and trigger the watch on with button PA0. The schematic when turned off still remains power for BKP and RTC section in Stm32f1 chip. So that make the watch lasts really long.
Power section im using TP4056 charger IC, regulator 3.3V AP2112.
2

PCB
3

Program layers

This part takes me so long to complete. Check out my github repo to fully comprehended