# Arduino Uno R3 Shield Template ## Description USB-C Powered ESP32-C3 + SHT45 Wi-Fi Temperature & Humidity Sensor Node ## Project Details - **Owner:** pcbxpressofficial - **Created:** 2/12/2026 - **Last Updated:** 2/12/2026 - **Visibility:** Public - **Domain:** Consumer Electronics - **Power Requirements:** USB - **System Architecture:** ```mermaid flowchart TD UC[USB-C Connector] CC1[CC1 Pull-down 5.1kΩ] CC2[CC2 Pull-down 5.1kΩ] PF[Fuse F1] REG[3.3V Regulator] V3[+3.3V Rail] GND[Ground] ESP[ESP32-C3 MCU] SHT[SHT45 Sensor] SDA[SDA Line] SCL[SCL Line] UART[UART Programming Pads] ANT[Ant. Keepout Region] UC -->|VBUS| PF --> REG -->|3.3V| V3 --> ESP V3 --> SHT GND --> ESP GND --> SHT UC -->|CC1| CC1 --> GND UC -->|CC2| CC2 --> GND ESP -->|SDA| SDA --> SHT ESP -->|SCL| SCL --> SHT ESP -->|TX/RX| UART ESP -.->|RF| ANT ``` - **PCB Stackup:** Standard 2-layer: Top=Signal, Bottom=Ground - **Connectivity:** WiFi ## Key Components ### ANT — [U.FL-R-SMT-1(10)](https://www.flux.ai/jecstronic/upfl-r-smt-110.md) - Datasheet URL: https://media.digikey.com/pdf/Data%20Sheets/Hirose%20PDFs/EDC3-302540-10.tif.pdf - Manufacturer Part Number: U.FL-R-SMT-1(10) - Connector Type: U.FL - PinLabels: Center_Contact=ANT, Outer_Contact=GND - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: RF antenna coaxial placeholder - Manufacturer Name: Hirose Electric Co Ltd - Silkscreen Label: ANT - Part Type: Connector - Role: Connector **Pins:** - Center_Contact [pin 2] - Outer_Contact [pin 1] - Outer_Contact [pin 3] ### D1 — [USBLC6-2SC6](https://www.flux.ai/lcsc/usblc6-2sc6.md) - LCSC Part Number: C2687116 - Manufacturer Part Number: USBLC6-2SC6 - Part Type: ESD Protection Devices - Role: Protection - Role Details: Transient voltage suppression for USB VBUS - Peak Pulse Current: 5A - JLCPCB Part Class: Extended Part - Maximum Clamping Voltage: 17V - Power: 150W - Manufacturer Name: UMW(友台半导体) - Package or Case Code: SOT-23-6_L2.9-W1.6-P0.95-LS2.8-BL - Operating Temperature: -55°C ~ 125°C (TJ) - Breakdown Voltage: 6V **Pins:** - GND [pin 2] - I/O1 [pin 1] - I/O1 [pin 6] - I/O2 [pin 3] - I/O2 [pin 4] - VBUS [pin 5] ### F1 — [0ZCJ0050FF2G](https://www.flux.ai/adrian95/0zcj0050ff2g.md) - License: https://creativecommons.org/licenses/by/4.0/ - Role Details: Overcurrent protection for USB VBUS - Manufacturer Part Number: 0ZCJ0050FF2G - Manufacturer Name: Bel Fuse Inc. - Part Type: Fuse - Datasheet URL: https://www.belfuse.com/resources/datasheets/circuitprotection/ds-cp-0zcj-series.pdf - Role: Protection **Pins:** - P1 [pin 1] - P2 [pin 2] ### J1 — [Pin Header 01x06 2.54mm Vertical](https://www.flux.ai/vasy_skral/pin-header-01x06-254mm-vertical.md) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] ### J10 — [YZ00515045R-07](https://www.flux.ai/lcsc/yz00515045r-07.md) - Package or Case Code: TESTPOINT-SMD_BD2.0-H7.0 - Manufacturer Name: Xinyangze(鑫扬泽) - JLCPCB Part Class: Extended Part - LCSC Part Number: C3001868 - Manufacturer Part Number: YZ00515045R-07 - Part Type: Pogo Pin Spring Probe Connector **Pins:** - 1 [pin 1] ### J11 — [Pin Header 01x02 2.54mm Vertical](https://www.flux.ai/jharwinbarrozo/pin-header-01x02-254mm-vertical.md) - Silkscreen Label: Servo 5V IN - Role Details: External servo 5V input header - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Role: Connector **Pins:** - P1 [pin 1] - P2 [pin 2] ### J2 — [Connector 01x08 0.100](https://www.flux.ai/vasy_skral/connector-01x08-0100.md) - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: Connector **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] - Pin_7 [pin 7] - Pin_8 [pin 8] ### J3 — [Pin Header 01x10 2.54mm Vertical](https://www.flux.ai/vasy_skral/pin-header-01x10-254mm-vertical.md) - Part Type: Connector **Pins:** - Pin_1 [pin 1] - Pin_10 [pin 10] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] - Pin_7 [pin 7] - Pin_8 [pin 8] - Pin_9 [pin 9] ### J4 — [Connector 01x08 0.100](https://www.flux.ai/vasy_skral/connector-01x08-0100.md) - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] - Pin_7 [pin 7] - Pin_8 [pin 8] ### J5 — [2171750001](https://www.flux.ai/jecstronic/2171750001.md) - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Part Number: 2171750001 - Part Type: USB C - Manufacturer Name: Molex - Role: Connector - Datasheet URL: https://www.molex.com/webdocs/datasheets/pdf/en-us/2171750001_IO_CONNECTORS.pdf - Role Details: USB Type-C receptacle for USB 2.0 device (Molex 2171790001) **Pins:** - CC1 [pin A5] - CC2 [pin B5] - GND [pin B12] - GND [pin A12] - SHIELD [pin S2] - SHIELD [pin S4] - SHIELD [pin S1] - SHIELD [pin S3] - VBUS [pin B9] - VBUS [pin A9] ### J5 — [2171750001](https://www.flux.ai/jecstronic/2171750001.md) - Manufacturer Name: Molex - Part Type: USB C - Manufacturer Part Number: 2171750001 - License: https://creativecommons.org/licenses/by/4.0/ - Datasheet URL: https://www.molex.com/webdocs/datasheets/pdf/en-us/2171750001_IO_CONNECTORS.pdf - Role Details: USB Type-C receptacle for USB 2.0 device (Molex 2171790001) - Role: Connector **Pins:** - CC1 [pin A5] - CC2 [pin B5] - GND [pin B12] - GND [pin A12] - SHIELD [pin S2] - SHIELD [pin S4] - SHIELD [pin S1] - SHIELD [pin S3] - VBUS [pin B9] - VBUS [pin A9] ### J6 — [Pin Header 01x06 2.54mm Vertical](https://www.flux.ai/vasy_skral/pin-header-01x06-254mm-vertical.md) - Role Details: Bluetooth HC-05/06 module interface - Pin 5 Label: NC - Pin 2 Label: GND - Pin 4 Label: RX - Pin Labels: Pin1=VCC, Pin2=GND, Pin3=TX, Pin4=RX, Pin5=NC, Pin6=NC - Role: Connector - Part Type: Connector - License: https://creativecommons.org/licenses/by/4.0/ - Pin 3 Label: TX - Pin 6 Label: NC - Pin 1 Label: VCC **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] ### J7 — [Pin Header 01x03 2.54mm Vertical](https://www.flux.ai/adrian95/pin-header-01x03-254mm-vertical.md) - Role: Connector - Role Details: Servo signal interface on D11 - PinLabels: Pin1=GND, Pin2=VCC, Pin3=SIG - Power Source: Arduino 5V - Part Type: Connector **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] ### J8 — [Pin Header 01x16 2.54mm Vertical](https://www.flux.ai/adrian95/pin-header-01x16-254mm-vertical.md) - License: https://creativecommons.org/licenses/by/4.0/ - PinLabels: Pin1=VCC, Pin2=GND, Pin3=D12, Pin4=D13, Pin5=NC, Pin6=NC, Pin7=NC, Pin8=NC, Pin9=NC, Pin10=NC, Pin11=NC, Pin12=NC, Pin13=NC, Pin14=NC, Pin15=NC, Pin16=NC - Interface: Parallel 1x16 - Role: Connector - Role Details: LCD interface on D12/D13 (plus reserved) - Part Type: Connector **Pins:** - Pin_1 [pin 1] - Pin_10 [pin 10] - Pin_11 [pin 11] - Pin_12 [pin 12] - Pin_13 [pin 13] - Pin_14 [pin 14] - Pin_15 [pin 15] - Pin_16 [pin 16] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] - Pin_5 [pin 5] - Pin_6 [pin 6] - Pin_7 [pin 7] - Pin_8 [pin 8] - Pin_9 [pin 9] ### J9 — [Pin Header 01x04 2.54mm Vertical](https://www.flux.ai/adrian95/pin-header-01x04-254mm-vertical.md) - Role Details: Wind sensor interface on A0–A2 - License: https://creativecommons.org/licenses/by/4.0/ - Pin 2 Label: A1 - Part Type: Connector - Role: Connector - PinLabels: Pin1=A0, Pin2=A1, Pin3=A2, Pin4=GND - Pin 3 Label: A2 - Pin 4 Label: GND - Pin 1 Label: A0 **Pins:** - Pin_1 [pin 1] - Pin_2 [pin 2] - Pin_3 [pin 3] - Pin_4 [pin 4] ### U1 — [USBLC6-2P6](https://www.flux.ai/kicad-part-library/usblc6-2p6.md) - Manufacturer Part Number: USBLC6-2P6 - Role Details: ESD protection array for USB D+ and D− lines - Datasheet URL: https://www.st.com/resource/en/datasheet/usblc6-2.pdf - Package or Case Code: SOT-666 - Manufacturer Name: Texas Instruments Inc. - Role: Protection **Pins:** - GND [pin 2] - I/O1 [pin 6] - I/O1 [pin 1] - I/O2 [pin 3] - I/O2 [pin 4] - VBUS [pin 5] ### U2 — [AMS1117-3.3](https://www.flux.ai/vasy_skral/ams1117-33.md) - Role Details: 5V→3.3V regulator for ESP32-C3 Wi-Fi peak current plus 25% margin - License: https://creativecommons.org/licenses/by/4.0/ - Package: SOT-223 - Manufacturer Part Number: AMS1117-3.3 - Role: Power Conversion - Part Type: Integrated Circuit - Datasheet URL: http://www.advanced-monolithic.com/pdf/ds1117.pdf - Manufacturer Name: AMS - Symbol Style: Parametric **Pins:** - GND [pin 1] - TAB(VOUT) [pin 4] - VIN [pin 3] - VOUT [pin 2] ### U3 — [ESP32-C3-WROOM-02U-N4](https://www.flux.ai/vasyl/esp32-c3-wroom-02u-n4.md) - Manufacturer Name: Espressif Systems - License: https://creativecommons.org/licenses/by/4.0/ - Part Type: RF module - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-c3-wroom-02_datasheet_en.pdf - Manufacturer Part Number: ESP32-C3-WROOM-02U-N4 - Role: Main MCU - Role Details: Ensure boot-strap pins are reserved and not used for other functions **Pins:** - 3V3 [pin 1] - EN [pin 2] - GND [pin 9] - GND__1 [pin 19] - GND__10 [pin 28] - GND__11 [pin 29] - GND__12 [pin 30] - GND__13 [pin 31] - GND__14 [pin 32] - GND__15 [pin 33] - GND__16 [pin 34] - GND__17 [pin 35] - GND__18 [pin 36] - GND__19 [pin 37] - GND__2 [pin 20] - GND__20 [pin 38] - GND__21 [pin 39] - GND__3 [pin 21] - GND__4 [pin 22] - GND__5 [pin 23] - GND__6 [pin 24] - GND__7 [pin 25] - GND__8 [pin 26] - GND__9 [pin 27] - IO0 [pin 18] - IO1 [pin 17] - IO10 [pin 10] - IO18 [pin 13] - IO19 [pin 14] - IO2 [pin 16] - IO3 [pin 15] - IO4 [pin 3] - IO5 [pin 4] - IO6 [pin 5] - IO7 [pin 6] - IO8 [pin 7] - IO9 [pin 8] - RXD [pin 11] - TXD [pin 12] ### U4 — [SHT40-AD1B-R2](https://www.flux.ai/lcsc/sht40-ad1b-r2.md) - Manufacturer Part Number: SHT40-AD1B-R2 - JLCPCB Part Class: Extended Part - Role: Sensor - Role Details: Temperature and humidity sensor with I2C interface - Package or Case Code: DFN-4_L1.5-W1.5-P0.8 - LCSC Part Number: C2909890 - Part Type: Humidity Sensors/Temperature and Humidity Sensors - Manufacturer Name: Sensirion(瑞士盛思锐) **Pins:** - EP [pin 5] - SCL [pin 2] - SDA [pin 1] - VDD [pin 3] - VSS [pin 4] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/pcbxpressofficial/arduino-uno-r3-shield-template](https://www.flux.ai/pcbxpressofficial/arduino-uno-r3-shield-template).* --- *Generated from [https://www.flux.ai/pcbxpressofficial/arduino-uno-r3-shield-template](https://www.flux.ai/pcbxpressofficial/arduino-uno-r3-shield-template)*