# USB-C ESP32 Environmental Node ## Description Low-power USB-C environmental sensor node using a dual-radio Wi‑Fi/BLE MCU, digital temperature/humidity sensing, protected 5 V USB-C input, and 3.3 V regulation for consumer use. ## Project Details - **Owner:** aleeeej - **Created:** 5/25/2026 - **Last Updated:** 5/26/2026 - **Visibility:** Public ## Key Components ### A1 — [Arduino-UNO-R3](https://www.flux.ai/jecstronic/arduino-uno-r3~kf3.md) - License: https://creativecommons.org/licenses/by/4.0/ - Role: Controller Board - Manufacturer Name: Arduino - Manufacturer Part Number: Arduino-UNO-R3 - Datasheet URL: https://media.digikey.com/pdf/Data%20Sheets/Arduino%20PDFs/A000066_Web.pdf - Part Type: Development Board - Role Details: Arduino Uno controller running the provided sketch; D9/D8/D10 control motor 1, D5/D6/D3 control motor 2, D0/D1 connect to Bluetooth serial. **Pins:** - +3V3 [pin 4] - +5V [pin 5] - AREF [pin 30] - D0/RX [pin 15] - D1/TX [pin 16] - D10 [pin 25] - D11 [pin 26] - D12 [pin 27] - D13 [pin 28] - D14/A0 [pin 9] - D15/A1 [pin 10] - D16/A2 [pin 11] - D17/A3 [pin 12] - D18/A4 [pin 13] - D18/SDA [pin 31] - D19/A5 [pin 14] - D19/SCL [pin 32] - D2 [pin 17] - D3 [pin 18] - D4 [pin 19] - D5 [pin 20] - D6 [pin 21] - D7 [pin 22] - D8 [pin 23] - D9 [pin 24] - GND [pin 6] - GND [pin 7] - GND [pin 29] - IOREF [pin 2] - NC [pin 1] - RESET [pin 3] - VIN [pin 8] ### BT1 — [HC-05](https://www.flux.ai/jecstronic/hc-05~ea.md) - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: HC-05 style serial Bluetooth module connected to Arduino D0/D1 for mobile command input. - Manufacturer Part Number: HC-05 - Role: Bluetooth UART Module - Datasheet URL: https://www.snapeda.com/parts/HC-05/ITead%20Studio/datasheet/ - Part Type: Module - Manufacturer Name: Itead Studio **Pins:** - ~RESETB [pin 11] - ~SPI_CSB [pin 16] - ~UART-CTS [pin 3] - ~UART-RTS [pin 4] - 3.3_VCC [pin 12] - AIO[0] [pin 9] - AIO[1] [pin 10] - GND [pin 13] - GND [pin 21] - GND [pin 22] - PCM-CLK [pin 5] - PCM-IN [pin 7] - PCM-OUT [pin 6] - PCN-SYNC [pin 8] - PIO[0] [pin 23] - PIO[1] [pin 24] - PIO[10] [pin 33] - PIO[11] [pin 34] - PIO[2] [pin 25] - PIO[3] [pin 26] - PIO[4] [pin 27] - PIO[5] [pin 28] - PIO[6] [pin 29] - PIO[7] [pin 30] - PIO[8] [pin 31] - PIO[9] [pin 32] - SPI_CLK [pin 19] - SPI_MISO [pin 18] - SPI_MOSI [pin 17] - UART-RX [pin 2] - UART-TX [pin 1] - USB_- [pin 15] - USB_+ [pin 20] ### J1 — [236-102](https://www.flux.ai/cherepanyadima/236-102~pe.md) - Symbol Style: Parametric - Manufacturer Part Number: 236-102 - Datasheet URL: https://wago.priintcloud.com/datasheets/236-102/en/ - Part Type: Connector - Role Details: Motor 1 output connector from L293D OUT1/OUT2; motor voltage is 9V rail switched by the H-bridge. - Role: Motor Connector - Manufacturer Name: https://wago.priintcloud.com/datasheets/236-102/en/ **Pins:** - ~ [pin L1] - ~ [pin L2] ### J2 — [236-102](https://www.flux.ai/cherepanyadima/236-102~pe.md) - Datasheet URL: https://wago.priintcloud.com/datasheets/236-102/en/ - Part Type: Connector - Manufacturer Part Number: 236-102 - Role: Motor Connector - Symbol Style: Parametric - Manufacturer Name: https://wago.priintcloud.com/datasheets/236-102/en/ - Role Details: Motor 2 output connector from L293D OUT3/OUT4; motor voltage is 9V rail switched by the H-bridge. **Pins:** - ~ [pin L1] - ~ [pin L2] ### J3 — [XY301V-A-5.0-2P](https://www.flux.ai/jharwinbarrozo/xy301v-a-50-2p~u6.md) - Part Type: Connector - Manufacturer Part Number: XY301V-A-5.0-2P - Role: Power Input Connector - Datasheet URL: https://www.lcsc.com/datasheet/C557651.pdf?spm=wm.sxq.inf.ggs&lcsc_vid=E1BYV1AHFgUMXgFVQ1AMU1JVQFReXgIATwJfA10DFVkxVlNRT1dXXlVTQ1hbUjsOAxUeFF5JWBYZEEoBGA4JCwFIFA4DSA%3D%3D - Role Details: 2-pin through-hole screw terminal for 9 V battery input; sized for motor current budget up to about 1.2 A continuous total. - Manufacturer Name: Ningbo Xinlaiya Elec. **Pins:** - PIN1 [pin 1] - PIN2 [pin 2] ### U1 — [L293D](https://www.flux.ai/vasy_skral/l293d~9wp.md) - Manufacturer Part Number: L293D - Role: Motor Driver - Manufacturer Name: STMicroelectronics - Symbol Style: Parametric - Role Details: L293D DIP-16 motor driver; VCC1=Arduino 5V logic, VCC2=9V motor battery rail; two bidirectional DC motors controlled by Arduino D9/D8/D10 and D5/D6/D3. - Datasheet URL: https://www.st.com/content/ccc/resource/technical/document/datasheet/04/ac/22/f9/20/5d/43/a1/CD00000059.pdf/files/CD00000059.pdf/jcr:content/translations/en.CD00000059.pdf - Part Type: Integrated Circuit - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - 1A [pin 2] - 1Y [pin 3] - 2A [pin 7] - 2Y [pin 6] - 3A [pin 10] - 3Y [pin 11] - 4A [pin 15] - 4Y [pin 14] - EN1,2 [pin 1] - EN3,4 [pin 9] - GND [pin 12] - GND [pin 5] - GND [pin 13] - GND [pin 4] - VCC1 [pin 16] - VCC2 [pin 8] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/aleeeej/usb-c-esp32-environmental-node~23](https://www.flux.ai/aleeeej/usb-c-esp32-environmental-node~23).* --- *Generated from [https://www.flux.ai/aleeeej/usb-c-esp32-environmental-node~23](https://www.flux.ai/aleeeej/usb-c-esp32-environmental-node~23)*