Temperature and Humidity Sensor Node Design

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

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

1:32

Read knowledge.

I’ll create a low‑power USB‑C (5 V) T/RH node with dual‑radio Wi‑Fi + BLE and robust input protection for 0.5–3 A sources.

Power: add USB‑C Receptacle, PTC Resettable Fuse, Power Path Protection IC (reverse/OVP/UVLO/OCP), Buck Regulator 3.3V, TVS Diode.
Core: add Wi‑Fi + BLE SoC, Digital Humidity and Temperature Sensor (I2C) with I2C Pull‑up Resistors; decoupling; RF keepouts.

Click Start on the plan bar to begin and I’ll execute these steps.

Plan

#Goal

Design and build a low‑power environmental sensor node that measures temperature and humidity. The node will feature dual‑radio Wi‑Fi (802.11 b/g/n) and BLE 5.x connectivity, and will be powered from a USB‑C 5 V supply. The design must include robust input protection (reverse polarity, OVP, UVLO, and OCP) and be capable of accepting USB‑C sources rated from 0.5 A up to 3 A.

#Implementation plan

Power Subsystem Design
1. Add a USB‑C receptacle with CC pull‑downs, ESD/TVS protection, and a PTC fuse.
2. Insert a power‑path protection circuit to provide reverse polarity, OVP, UVLO, and OCP protections. Size components to handle currents in the range of 0.5–3 A.
3. Add a 5 V to 3.3 V buck regulator circuit and associated decoupling capacitors.
Core Components and Connectivity
1. Select and add a dual‑radio Wi‑Fi (802.11 b/g/n) + BLE 5.x MCU/module to the schematic.
2. Add a digital temperature/humidity sensor with I2C interface.
3. Connect the I2C sensor to the MCU using appropriate pull‑up resistors (2.2–4.7 kΩ) on the SDA and SCL lines.
4. Add necessary programming/boot and reset pins from the MCU/module.
Schematic Creation and Verification
1. Define and make all connections between the USB‑C power input, the protection components, the buck regulator, and the load (MCU/module and sensor).
2. Ensure that RF antenna nets and keepouts are properly set to minimize interference in the design.
3. Run ERC/DRC checks to verify connectivity and placement of protection and decoupling components.
Project Documentation
1. Update the project description with the design goals and selected major components.
2. Prepare a preliminary BOM covering all key components such as the USB‑C connector, MCU/module, sensor, buck regulator, and protection circuits.

#Success criteria

The schematic includes a full USB‑C 5 V power input stage with reverse polarity, OVP, UVLO, and OCP protections adequately rated for 0.5–3 A sources.
The design integrates a dual‑radio Wi‑Fi (802.11 b/g/n) + BLE 5.x MCU/module with an I2C digital temperature/humidity sensor and proper RF and component connections.
ERC/DRC checks pass without critical errors, ensuring the design meets the low‑power and robust protection requirements.

Select CC pull-downs

Choose PTC fuse

Pick buck regulator

Add MCU module

Add T/RH sensor

Reviews

Generic Inductor
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Project Name

Sharp Beige Warp Drive

Description

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Properties

Properties describe core aspects of the project.

Pricing & Availability

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