USB-C Temperature and Humidity Sensor Design

Make me a temperature and humidity sensor node with Wifi and Bluetooth, powered by USB-C (5V) for consumer use.

It should be a low-power environmental node with a digital T/RH sensor, ultra-low-power MCU with Wi-Fi + Bluetooth (dual-radio) — 2.4 GHz 802.11 b/g/n plus BLE 5.x powered by USB-C (5 V) — USB-C receptacle 5 V default; include reverse/OVP/UVLO/OCP protection and plan for 0.5–3 A sources.

flux

1:11

Analyzing in depth.

Read BOM.

Read layout.

Read schematic.

Thought for a moment

Analyzing in depth.

Thought for a moment

You want a consumer USB-C powered Wi-Fi/Bluetooth temperature and humidity sensor node.

I’ve built the plan to:
1. Define the system architecture
2. Implement USB-C 5 V power entry and protection
3. Add the wireless MCU and digital T/RH sensor
4. Finalize the schematic for PCB-ready implementation

This follows Flux’s planning/modification workflow guidance . Click Start on the plan bar to have it built.

Plan

#Goal

Design a consumer low-power temperature and humidity sensor node powered by a USB-C 5 V sink equipped with reverse polarity, over-voltage, under-voltage, and over-current protection. The node uses an ultra-low-power MCU that supports 2.4 GHz 802.11 b/g/n Wi-Fi and BLE 5.x, and incorporates a digital temperature/humidity sensor. The design will accommodate USB-C sources delivering currents from 0.5 A to 3 A.

#Implementation plan

Define System Architecture
1. Document the power entry from the USB-C connector using default 5 V sink behavior.
2. Outline and add the protection circuitry for reverse polarity, over-voltage, under-voltage, and over-current events.
Implement Power Management
1. Add a USB-C connector and design the power path including protection devices (e.g., diodes/FETs, voltage supervisors, and fuses).
2. Establish regulated rails to power the MCU and sensor.
Integrate Key Components
1. Select and add an ultra-low-power MCU with integrated 2.4 GHz Wi-Fi and BLE 5.x connectivity.
2. Select and add a digital temperature/humidity sensor, and establish the necessary I2C or digital interface connections.
Finalize Circuit Design
1. Connect and route protection circuits to the power supply path.
2. Ensure proper decoupling, grounding, and layout for RF and EMC considerations.
3. Prepare schematic for PCB layout with design rules for manufacturability.

#Success criteria

A complete schematic that integrates USB-C power entry with full protection circuitry and regulated power rails.
Fully connected ultra-low-power MCU and digital T/RH sensor with proper RF and interface considerations.
Design meets the requirement for operating from USB-C sources between 0.5 A and 3 A.

Add ESD protection

Use ESP32-C6

Set 500mA limit

Finished working

Reviews

Generic Inductor
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Project Name

New Harlequin Jetpack

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ritwik55 / New Harlequin Jetpack

Schematic