# USB-C WiFi BLE T-RH Sensor Node ## Description Consumer USB-C powered low-power temperature and humidity sensor node with Wi-Fi/BLE connectivity, I2C digital T/RH sensing, and protected 5 V input power management. ## Project Details - **Owner:** revworks - **Created:** 5/12/2026 - **Last Updated:** 5/12/2026 - **Visibility:** Public - **Domain:** Consumer Electronics - **Operating Voltage:** 5V - **Power Requirements:** USB - **Implementation Details:** USB-C 5 V default sink; 3.3 V rail; Wi-Fi/BLE MCU module; I2C digital T/RH sensor; reverse/OVP/UVLO/OCP input protection planned for 0.5 A to 3 A sources - **Connectivity:** WiFi ## Key Components ### J1 — [USB-C 2.0 Receptacle](https://www.flux.ai/vasy_skral/usb-c-2p0-receptacle~1xw.md) - Datasheet URL: https://gct.co/files/drawings/usb4105.pdf - Role Details: Power-only USB-C 5 V default sink; CC1 and CC2 each use 5.1 kΩ Rd to GND - Purchase Url: https://www.digikey.com/en/products/detail/gct/USB4105-GF-A/11198441 - Manufacturer Part Number: USB4105-GF-A - Symbol Style: parametric-v1 - Manufacturer Name: GTC - Part Type: USB C - Role: USB-C power input **Pins:** - CC1 [pin 6] - CC2 [pin 12] - D- [pin 7] - D- [pin 9] - D+ [pin 10] - D+ [pin 8] - GND [pin 1] - GND [pin 16] - GND [pin 15] - GND [pin 2] - SBU1 [pin 11] - SBU2 [pin 5] - VBUS [pin 3] - VBUS [pin 14] - VBUS [pin 4] - VBUS [pin 13] ### U1 — [ESP32-C3-MINI-1-N4](https://www.flux.ai/jecstronic/esp32-c3-mini-1-n4~wbz.md) - Symbol Style: parametric-v1 - Role: Wi-Fi/BLE MCU module - Datasheet URL: https://www.espressif.com/sites/default/files/documentation/esp32-c3-mini-1_datasheet_en.pdf - Operating Voltage: 3.3V - Role Details: ESP32-C3 module with 2.4 GHz Wi-Fi 802.11 b/g/n and Bluetooth 5 LE; antenna requires edge keepout - Connectivity: WiFi - Part Type: Integrated Circuit - Manufacturer Part Number: ESP32-C3-MINI-1-N4 - Manufacturer Name: Espressif Systems - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - 3V3 [pin 3] - EN [pin 8] - GND [pin 51] - GND [pin 36] - GND [pin 49_9] - GND [pin 1] - GND [pin 49_6] - GND [pin 46] - GND [pin 49_3] - GND [pin 43] - GND [pin 49_7] - GND [pin 39] - GND [pin 14] - GND [pin 41] - GND [pin 37] - GND [pin 53] - GND [pin 42] - GND [pin 49_2] - GND [pin 49_1] - GND [pin 45] - GND [pin 11] - GND [pin 38] - GND [pin 52] - GND [pin 2] - GND [pin 48] - GND [pin 49_4] - GND [pin 40] - GND [pin 49_5] - GND [pin 49_8] - GND [pin 44] - GND [pin 47] - GND [pin 50] - IO0 [pin 12] - IO1 [pin 13] - IO10 [pin 16] - IO18 [pin 26] - IO19 [pin 27] - IO2 [pin 5] - IO3 [pin 6] - IO4 [pin 18] - IO5 [pin 19] - IO6 [pin 20] - IO7 [pin 21] - IO8 [pin 22] - IO9 [pin 23] - NC [pin 35] - NC [pin 4] - NC [pin 10] - NC [pin 32] - NC [pin 7] - NC [pin 9] - NC [pin 28] - NC [pin 24] - NC [pin 15] - NC [pin 34] - NC [pin 29] - NC [pin 17] - NC [pin 33] - NC [pin 25] - RXD0 [pin 30] - TXD0 [pin 31] ### U2 — [SHTC3-TR-2.5KS](https://www.flux.ai/adrian95/shtc3-tr-2p5ks~af.md) - Part Type: Sensor - Datasheet URL: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/906/HT_DS_SHTC3_D1.pdf - Role: Digital T/RH sensor - License: https://creativecommons.org/licenses/by/4.0/ - Manufacturer Name: Sensirion AG - Operating Voltage: 3.3V - Manufacturer Part Number: SHTC3-TR-2.5KS - Symbol Style: parametric-v1 - Role Details: I2C temperature and relative humidity sensor powered from 3.3 V; keep away from heat sources and provide air exposure **Pins:** - EPAD [pin 5] - SCL [pin 2] - SDA [pin 3] - VDD [pin 1] - VSS [pin 4] ### U3 — [TPS25940LRVCR](https://www.flux.ai/adrian95/tps25940lrvcr~ojd.md) - Manufacturer Name: Texas Instruments - Manufacturer Part Number: TPS25940LRVCR - Part Type: Integrated Circuit - Role: Input eFuse protection - Datasheet URL: https://www.ti.com/lit/ds/symlink/tps25940.pdf - Role Details: Protected 5 V power path with programmable OVP, UVLO, OCP/current limit and reverse-current blocking for 0.5 A to 3 A USB-C sources - License: https://creativecommons.org/licenses/by/4.0/ **Pins:** - ~FLT [pin 20] - DEVSLP [pin 1] - DVDT [pin 18] - EN [pin 14] - EP [pin 21] - GND [pin 16] - ILIM [pin 17] - IMON [pin 19] - IN_1 [pin 9] - IN_2 [pin 10] - IN_3 [pin 11] - IN_4 [pin 12] - IN_5 [pin 13] - OUT_1 [pin 4] - OUT_2 [pin 5] - OUT_3 [pin 6] - OUT_4 [pin 7] - OUT_5 [pin 8] - OVP [pin 15] - PGOOD [pin 2] - PGTH [pin 3] ### U4 — [AP2112K-3.3TRG1](https://www.flux.ai/adrian95/ap2112k-33trg1~zlq.md) - Role Details: 600 mA LDO from protected 5 V to 3.3 V rail; includes overcurrent and thermal protection - License: https://creativecommons.org/licenses/by/4.0/ - Max Output Voltage: 3.3V - Role: 3.3 V regulator - Datasheet URL: https://www.diodes.com/assets/Datasheets/AP2112.pdf - Max Current: 0.6A - Symbol Style: parametric-v1 - Part Type: Integrated Circuit - Manufacturer Part Number: AP2112K-3.3TRG1 - Manufacturer Name: Diodes Incorporated **Pins:** - EN [pin 3] - GND [pin 2] - NC [pin 4] - VIN [pin 1] - VOUT [pin 5] *The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/revworks/usb-c-wifi-ble-t-rh-sensor-node~ry](https://www.flux.ai/revworks/usb-c-wifi-ble-t-rh-sensor-node~ry).* --- *Generated from [https://www.flux.ai/revworks/usb-c-wifi-ble-t-rh-sensor-node~ry](https://www.flux.ai/revworks/usb-c-wifi-ble-t-rh-sensor-node~ry)*