USB-C Sensor Node

Worked for 4 mins 24 sec

Implemented the schematic for the USB-C powered Wi‑Fi/BLE temperature/humidity node. It uses a SiWG917 Wi‑Fi/BLE 5.4 module, SHT41 T/RH sensor, USB-C sink input, TPS25940 true reverse-blocking eFuse with OVP/UVLO/OCP/soft-start, MP28301 3.3 V buck regulator, ESD protection, reset/ISP/SWD debug, I2C pull-ups, and status LED.

Created project files:

Open items:

PCB layout/routing is not done yet, so airwire DRC errors are expected.
Generic passives still need final manufacturer MPNs before manufacturing export.
Layout must enforce the SiWG917 antenna keepout and thermal isolation around the SHT41.

Suggested next steps:

Set board size/stackup and move into PCB placement.
Place U1 at the board edge with antenna keepout and U4 away from heat sources.
Route power, buck, I2C, SWD/UART, and USB-C protection paths.
Assign final passive MPNs and run full DRC/manufacturing checks.

benjaminzeisberg

great let's finish the schematic and then let's generate the PCB board

Thought for 5 sec

flux

The schematic is functionally complete: 46 components cover USB-C input, ESD, TPS25940 reverse/OVP/UVLO/OCP protection, MP28301 3.3 V regulation, SiWG917 Wi‑Fi/BLE, SHT41 sensing, debug controls, and support circuitry. Electrical schematic checks were clean; unrouted airwires and missing final passive MPNs remain expected at this stage.

I can’t generate the PCB now because the account has no available ACUs, so AI execution is unavailable. Once ACUs are available, the remaining work is:

Final schematic visual cleanup and verification.
Assign final passive MPNs.
Set board dimensions, stackup, and design rules.
Place the antenna module at the edge with its all-layer keepout.
Thermally isolate the SHT41 from the MCU and buck regulator.
Route, add planes/stitching, and resolve DRC.
Generate manufacturing files.

Finalize passives and BOM

Document PCB requirements

Review BOM sourcing

Reviews

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
16.7k
Generic Capacitor
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jharwinbarrozo
1.5M
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
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
RMCF0805JT47K0
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jharwinbarrozo
1.2M
875105359001
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CTL1206FYW1T
Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric)
jharwinbarrozo
1.1M
1070TR
Battery Holder (Open) Coin, 20.0mm 1 Cell SMD (SMT) Tab bate or batt #forLedBlink
jharwinbarrozo
700.5k
Push Button
A momentary or non-latching switch which causes a temporary change in the state of an electrical circuit only while the switch is physically actuated. SWITCH TACTILE SPST-NO 0.05A 24V
jharwinbarrozo
490.7k
T491D226K025AT
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vasyl
448.3k

Project Name

USB-C WiFi BLE TH Sensor

Description

Consumer USB-C powered environmental sensor node with Wi-Fi, BLE 5.x, digital temperature/humidity sensing, protected 5 V input, and a 3.3 V low-power MCU/sensor rail.

Properties

Connectivity

WiFi

Power R…rements

USB-C

Domain

Consumer IoT

Operating Voltage

Connectivity

Bluetooth

Pricing & Availability

Distributor	Qty 1
Arrow	$4.10–$6.58
Digi-Key	$0.00
HQonline	$3.72–$3.82
LCSC	$5.53–$5.70
Mouser	$26.56
TME	$0.00
Verical	$5.53–$8.26

Controls

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benjaminzeisberg / USB-C WiFi BLE TH Sensor

Schematic