USB-C Sensor Node


Worked for 52 sec
6/6 Run schematic/design checks and fix actionable issues

Rename project, create specification, and record initial requirements/power budget

Select library parts for MCU, T/RH sensor, USB-C input, regulator, and protection

Add main components and supporting passives to the schematic

Wire USB-C power/protection, 3.3 V rail, MCU boot/debug, USB data, I2C sensor, and indicators

Create firmware/regulatory/bring-up project files

Run schematic/design checks and fix actionable issues

Thought for 46 sec
Reading project docs.
Getting a BOM overview.
Completed 11 design checks — found 114 issues.
Thought for 42 sec — Verifying eFuse features
Read U2, TPS259530DSGT datasheets.
Thought for a moment
Searching for eFuse solutions
I need to address the issue with TPS2596 that requires fixing since the user needs the reverse. It looks like I have to replace or add an ideal diode. To do that, I should search for a part with back-to
Worked for 10 sec
Thought for a moment
Searching for eFuse solutions
I need to address the issue with TPS2596 that requires fixing since the user needs the reverse. It looks like I have to replace or add an ideal diode. To do that, I should search for a part with back-to-back eFuse in the library. It’s essential to find the right replacement to meet the user's requirements. Let’s get started on that!
The core schematic has been drafted with a SiWG917 Wi‑Fi/BLE module, SHT41 temperature/humidity sensor, USB‑C 5 V input, protected power path, and 3.3 V buck rail. Firmware, bring-up, and regulatory planning were also started.
I can’t inspect the attached text or continue verification because no ACUs are currently available. Remaining work: review the attachment, finish ERC/DRC remediation, confirm protection and power-budget ratings for 0.5–3 A USB sources, and complete PCB placement/routing.
Review attached requirements
Check power protection
Check ERC and DRC

U2
D1
J1
U1
Technical Construction File — USB-C WiFi BLE TH Sensor
Status
Draft — schematic-stage regulatory file.
Applicable Regulations
  • FCC Part 15 intentional radiator / unintentional radiator
  • CE RED for EU radio equipment
  • ISED Canada if sold in Canada
  • UKCA if sold in the UK
  • RoHS/REACH for consumer production
Product Description
USB-C powered indoor consumer temperature/humidity sensor node using a Silicon Labs SiWG917 Wi-Fi/BLE module and Sensirion SHT41 digital T/RH sensor.
Wireless Technology Summary

Table


ModuleMPNTechnologyFrequency BandAntennaNotes
U1SIWG917Y111MGABARWi-Fi 2.4 GHz 802.11 b/g/n/ax + BLE 5.42.4 GHz ISMIntegrated antenna variantMust follow Silicon Labs integration/keepout guidance
Required Documentation Checklist
  • Product block diagram — included in Project Specification
  • Draft BOM from schematic — available in Flux BOM
  • RF integration notes — included below
  • Draft Declaration of Conformity — created in this file
  • User manual outline — included below
  • Final schematic PDF export
  • Final PCB layout/Gerbers after layout
  • Module certification grants and integration manual from Silicon Labs
  • EMC/RF test reports from accredited lab
  • Final product labels with FCC/CE/UKCA marking
RF Design Notes
  • U1 must be placed at a PCB edge with the integrated antenna facing outward.
  • Keep the antenna clearance void of copper, traces, vias, components, and metal on all layers.
  • Keep U3/L1 buck regulator switch node and inductor away from U1 antenna region.
  • Maintain solid ground under the module body where allowed by the module datasheet.
  • Do not change the module antenna or add metal/plastic in direct contact with the antenna without RF validation.
Draft Declaration of Conformity
We, [Company Name], declare that the product USB-C WiFi BLE TH Sensor is designed to conform to applicable FCC Part 15, CE RED, RoHS, and EMC requirements when manufactured and integrated according to the final approved schematic, PCB layout, BOM, RF module integration guide, and user manual.
Authorized signatory: ____________________ Date: ____________________
User Manual Outline
  • Product overview and intended indoor consumer use.
  • USB-C 5 V power-only input requirements.
  • Wireless setup/provisioning instructions.
  • Temperature/humidity measurement limitations; avoid direct sunlight, condensation, and heat sources.
  • Regulatory notices: FCC Part 15 statements, CE/UKCA marking, RF exposure statement, no user-serviceable RF modifications.
  • Disposal and RoHS/WEEE notes.
Open Items
  • Confirm exact SiWG917 certification IDs and approved integration conditions.
  • Add final PCB layout screenshots/exports after layout.
  • Run EMC pre-scan with USB cable attached and Wi-Fi/BLE active.
  • Status

  • Applicable Regulations

  • Product Description

  • Wireless Technology Summary

  • Required Documentation Checklist

  • RF Design Notes

  • Draft Declaration of Conformity

  • User Manual Outline

  • Open Items