USB-C Temperature Humidity Sensor Node Design

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I’m blocked because the project has no available ACUs, so I can’t continue executing design actions or run validation.
Completed so far:
  • Renamed the project to USB-C WiFi BLE Sensor Node and updated its description/properties.
  • Selected and added the main schematic parts:
    • ESP32-C3-MINI-1-N4 Wi‑Fi/BLE module
    • Sensirion SHT40 T/RH sensor
    • USB-C receptacle
    • TPS259474 eFuse for OVP/UVLO/OCP/reverse-current blocking
    • AP2112K-3.3 600 mA LDO
    • HUSB238A USB-C/PD sink/current-detection controller
    • USB ESD protection, reset/boot switches, status LED, and support passives
  • Consulted datasheets for ESP32-C3, SHT40, and AP2112K:
    • ESP32-C3 needs 3.0–3.6 V, ≥0.5 A supply capability, EN not floating, GPIO9 boot pull-up, GPIO18/19 as USB D−/D+.
    • SHT40 runs from 1.08–3.6 V, I2C address 0x44, needs I2C pull-ups and local decoupling.
    • AP2112K uses 1 µF min input/output capacitors, EN high for normal operation.
Remaining work:
  • Finish datasheet checks for TPS259474, HUSB238A, USB-C connector, and USBLC6 ESD part.
  • Correct individual passive values/properties where needed.
  • Wire the full schematic: USB-C, CC/PD controller, eFuse, 3.3 V rail, ESP32, SHT40, I2C, USB data, reset/boot, LED.
  • Run schematic review/ERC and fix violations.
  • Create the required project files: project specification, power budget, firmware starter, FCC/CE regulatory notes, and board bring-up plan.
Check power ICs
Wire schematic
Run review
Power budget doc
Compliance docs
U2
  • Generic Inductor
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    jharwinbarrozo
    16.5k
  • 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
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    20.5M
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    Terminal
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    natarius
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    jharwinbarrozo
    1.2M
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    875105359001
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    CTL1206FYW1T
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    1.1M
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USB-C WiFi BLE Sensor Node

USB-C WiFi BLE Sensor Node thumbnail
Consumer USB-C powered low-power environmental sensor node with Wi-Fi, Bluetooth LE, digital temperature/humidity sensing, and protected 5 V input supporting 0.5–3 A USB-C sources.

Properties

2.4 GHz Wi-Fi 802.11 b/g/n and Bluetooth LE 5.x

USB-C sink default 5 V; design power path for 0.5–3 A advertised sources with input OVP/UVLO/OCP/reverse protection

Consumer environmental IoT sensor node

USB-C 5 V input, regulated 3.3 V system rail

Pricing & Availability

Distributor

Qty 1

Arrow

$2.20–$2.93

Digi-Key

$3.53–$3.65

HQonline

$3.33–$3.43

LCSC

$6.83–$7.00

Mouser

$4.83

TME

$2.87

Verical

$1.96–$3.83

Controls