Wi-Fi/BLE Temperature Sensor Node Design

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Parts selected: ESP32‑C6 module, Sensirion SHT41 I²C T/RH sensor, USB‑C receptacle, TI TPS25940L eFuse protection, and a low-Iq 3.3 V buck regulator. I’m adding the schematic now.

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Schematic wiring is in place for USB-C sink detection, protected 5 V, 3.3 V regulation, ESP32-C6 power/enable, and the SHT41 I²C interface. I’m checking and annotating it now.

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Built the USB-C powered Wi‑Fi/BLE temperature/humidity sensor node schematic and renamed the project to USB-C Wi-Fi BLE Environmental Sensor Node. It includes USB-C 5 V sink Rd resistors, TPS25940L input protection, 3.3 V low-Iq buck regulation, ESP32-C6-WROOM-1-N8, SHT41 I²C T/RH sensor, decoupling/bulk passives, net metadata, and ERC verification with no reported electrical warnings in the checked categories.
I also added project docs:
  • USB-C Wi-Fi/BLE Environmental Sensor Node (usb-c-wi-fible-environmental-sensor-node)
  • Bring-Up, Firmware, and Compliance Plan (bring-upc-firmwarec-and-compliance-plan)
Next step is PCB layout: place the USB-C/protection/regulator block, isolate the sensor from heat sources, and enforce the ESP32-C6 antenna keepout.
Start PCB layout
Tune protection values
Add programming access
Run schematic review
Optimize low power
U1
U2 SDA - U1 IO6
L1 ~ - U4 OUT1
L1 ~ - U4 OUT1
  • Generic Inductor
    Generic Inductor
    A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
    jharwinbarrozo
    16.5k
  • Generic Capacitor
    Generic Capacitor
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    jharwinbarrozo
    1.5M
  • Generic Resistor
    Generic Resistor
    A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
    jharwinbarrozo
    1.5M
  • Ground
    Ground
    A common return path for electric current. Commonly known as ground.
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    20.5M
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    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
    natarius
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    Net Portal
    Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
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    43.0M
  • RMCF0805JT47K0
    RMCF0805JT47K0
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    1.2M
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    875105359001
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    CTL1206FYW1T
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    jharwinbarrozo
    1.1M
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    1070TR
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USB-C Wi-Fi BLE Environmental Sensor Node

USB-C Wi-Fi BLE Environmental Sensor Node thumbnail
Consumer USB-C powered low-power temperature/humidity sensor node with ESP32-C6 Wi-Fi/BLE and protected 5 V input

Properties

WiFi, Bluetooth

USB-C 5 V default sink; protected path planned for 0.5–3 A sources

USB-C 5 V input, internal 3.3 V rail

Consumer product; use certified radio module and plan FCC/CE/UKCA verification

Consumer IoT environmental sensing

Pricing & Availability

Distributor

Qty 1

Arrow

$2.85–$3.76

Digi-Key

$6.05

HQonline

$0.10

LCSC

$6.64

Mouser

$14.06

TME

$6.19

Verical

$1.32–$3.59

Controls