Hardware Schematics

Exposed pads

The board was designed with an Open Source philosophy in mind, therefore a few relevant pins are exposed on the pads illustrated below. A user can solder wires to these pads and customise the uThing::VOC board to extend the default functionalities, or prototype new ideas.

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The table below details the connection of the exposed pads and the alternative GPIO functions available:

ID Pin # Signal name Comment
B6 42 PB.6 I2C1_SCL (a 2nd I2C bus to avoid any interfering with the BME680)
B7 43 PB.7 I2C1_SDA
A3 13 PA.3 exposes an ADC channel and a timer (PWM out or counter in)
A4 14 PA.4 mapped to an ADC, DAC & Timer channels
TXD 30 PA.9 USART1_TXD, TIM1_CH2 (PWM)
RXD 31 PA.10 USART1_RXD, TIM1_CH3 (PWM)
GD 8,23,35,47 GND System reference ground

Circuit Schematic

uThing::VOC revision 1 schematic:

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(PDF version here)

For more information please check the STM32F072CB datasheet

Design files - source code

The design files (Gerbers, Bill of Materials, Schematics), along with the Firmware source code can be found in the project’s GitHub repositories: