Temperature and Humidity Sensor Node 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

1:52

Thought for 3s

Analyzing in depth.

Thought for a moment

Analyzing in depth.

Thought for 12s

Thought for a moment

Analyzing in depth.

Thought for a moment

I've made a plan, and started work on it.

Plan

#Goal

Design a low-power, consumer-grade temperature and humidity sensor node with integrated Wi-Fi and Bluetooth connectivity. The design will utilize an ultra-low-power MCU with dual-radio support (for 2.4 GHz 802.11 b/g/n and BLE 5.x) and a digital temperature/relative-humidity sensor. It will be powered from a USB-C receptacle and include robust input protection (reverse polarity, over-voltage, under-voltage lockout, and over-current protection for 0.5A to 3A sources).

#Implementation plan

System and Project Setup
1. Update the project description with the system goals and consumer-grade application requirements.
2. Define the top-level system architecture including power supply, sensor input, wireless communications, and protection circuits.
Component Selection and Schematic Creation
1. Select and add the ultra-low-power MCU with integrated dual-radio (Wi-Fi and BLE) from the parts library (for example, an ESP32 variant if available).
2. Select and add a digital temperature/relative-humidity sensor (e.g., SHT31/SHTC3) suitable for environmental sensing.
3. Select and add a USB-C receptacle with standard 5V input behavior.
Protection and Power Regulation
1. Add input protection components in the schematic:
  1. Include reverse polarity protection (using protection diodes or an ideal diode circuit).
  2. Add an over-voltage protection circuit (utilize TVS diodes or a dedicated regulator with over-voltage cutoff).
  3. Incorporate an under-voltage lockout circuit to ensure safe power operation.
  4. Add over-current protection (using fuses or resettable polyfuses) to cover the 0.5A to 3A input range.
2. Add supporting components for power regulation (consider a buck converter/regulator from 5V to the MCU’s operating voltage, likely 3.3V) and bypass capacitors for filtering.
Schematic Connectivity and Review
1. Connect the USB-C input to the protection circuitry and then to the power regulator.
2. Connect the regulated power rail to the MCU and sensor circuits.
3. Connect the sensor to the MCU via the appropriate digital interface (I²C or SPI as required).
4. Validate connections ensuring proper routing of power and signal nets.
Final Schematic and Metadata Update
1. Review the complete schematic for low-power performance and consumer-use robustness.
2. Update project metadata with key design decisions and component selections for future PCB layout integration.

#Success criteria

The design includes an ultra-low power MCU with integrated dual-radio connectivity (Wi-Fi and BLE) and a digital temperature/humidity sensor.
The USB-C power input is robustly protected against reverse polarity, over-voltage, under-voltage, and over-current conditions.
All power regulation stages and supporting components are correctly connected and documented for low-power operation in a consumer environment.
The project is ready for schematic review and subsequent PCB layout integration.

Add ESD protection

Prefer SHTC3 sensor

Place antenna at edge

Ready to work

Reviews

Generic Inductor
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