USB-C Temperature and Humidity Sensor Design

0:28

Clarifying image analysis.

That screenshot looks like a compact 4-layer automotive dongle-style PCB reference, and the main takeaway for your current project is its placement strategy, not its exact circuitry. Per the attachment-analysis workflow, the right way to use an uploaded image like this is to extract the visible architecture and relate it to your open design context rather than treat it in isolation

For your USB-C environmental sensor node, the useful ideas to borrow are:

Put the input connector and protection stage together near the board edge
Keep the MCU/module in a clean area with short power decoupling paths
Reserve a clear antenna keep-out at the board edge if you use a radio module
Keep the sensor away from local heat sources like the regulator and protection IC
Use the 4-layer structure as:
- L1: signals/components
- L2: solid GND
- L3: 5 V / 3.3 V distribution
- L4: secondary signals + local GND pour

What does not carry over well from that reference:

Automotive connector placement and 12 V protection assumptions
High-current/vehicle-interface routing priorities
OBD-style mechanical outline

So: yes, it is a good layout reference for floorplanning, especially connector-edge placement, RF keep-out discipline, and power-entry clustering. But for your project, I’d adapt it into a USB-C on one edge, protection + regulator immediately behind it, MCU near antenna edge, sensor thermally isolated layout.

If you want, I can next:

set your board to a 4-layer layout,
size it for a small consumer sensor node,
and define the placement/rule strategy for the current project.

Set 4-layer stackup

Suggest board size

Place key blocks

18 days

U1 LX3 - U2 VIN

U3 EN - R5 P2

J1 VBUS_A - J1 VBUS_B

U2 VOUT - U3 3V3

J1 VBUS_A - J1 VBUS_B

U4 SCL - U3 IO5

U4 SDA - U3 IO4

U2 VOUT - U3 3V3

J1 VBUS_A - J1 VBUS_B

J1 CC2 - R2 P1

J1 CC1 - R1 P1

U1 LX3 - U2 VIN

J1 VBUS_A - J1 VBUS_B

U2 EN - U1 VCC

J1 CC2 - R2 P1

U2 EN - U1 VCC

J1 CC1 - R1 P1

U4 SCL - U3 IO5

U2 EN - U1 VCC

U4 SDA - U3 IO4

U2 VOUT - U3 3V3

J1 VBUS_A - J1 VBUS_B

J1 SHELL_GND - R1 P2

Capacitance

100nF

J1 SHELL_GND - R1 P2

U3 GND - U4 VSS

Capacitance

10uF

Resistance

5.1kΩ

U1 PAD - U2 GND

Resistance

5.1kΩ

GND

U1 PAD - U2 GND

GND

J1 SHELL_GND - R1 P2

Capacitance

10uF

Capacitance

1uF

U3 GND - U4 VSS

J1 SHELL_GND - R1 P2

Reviews

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A common return path for electric current. Commonly known as ground.
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Project Name

USB-C Environmental Sensor Node

Description

Low-power consumer environmental sensor node powered from USB-C 5 V. Includes USB-C sink power entry with reverse polarity, OVP, UVLO, and OCP protection for 0.5 A to 3 A sources, 3.3 V regulation, an ultra-low-power Wi-Fi plus BLE MCU, and a digital temperature/humidity sensor connected over I2C. Intended as a schematic foundation for reliable PCB layout and manufacturing.

Properties

Properties describe core aspects of the project.

Pricing & Availability

Distributor	Qty 1
Arrow	$2.65–$3.62
Digi-Key	$3.59–$3.91
LCSC	$7.84–$7.88
Mouser	$5.79
TME	$3.75
Verical	$4.37–$4.67

Controls

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spypol19 / USB-C Environmental Sensor Node

Schematic