Imported from GitHub: cegea/temperature_node_hw · commit ae33526 · license GPL-3.0

Description

PCB design for a temperature sensor based on SHT and ESP32

README

Temperature node

PCB design for a temperature sensor based on SHT and ESP32.

Requirement Specifications

• Battery Operated: The node should operate on a battery with a lifespan of over a month.
• WiFi Connection: Supports 2.4 GHz WiFi to connect to a home network.
• MQTT Protocol: Publishes temperature and humidity data to an MQTT broker.
• Compact Design: Designed for easy placement in various locations around the home.
• Temperature and Humidity Reporting: Uses an SHT series sensor for accurate measurements.

Functional Requirements Specification

Electrical

• Battery Life: Should last more than a month on a single charge.
• Power Consumption: Optimized deep-sleep mode for low power consumption between readings.
• Input Voltage: 3.3V for ESP32 and 3V to 5V compatible for SHT sensors.
• Charging: Option for USB-C charging or solar panel for extended battery life.
• Voltage Regulation: Include a voltage regulator to ensure stable power delivery to ESP32 and the sensor.

Mechanical

• Enclosure: IP65-rated enclosure for dust and water resistance if placed in areas prone to moisture.
• Size: Compact size, around 5cm x 5cm x 3cm, to fit easily on shelves or mounted on walls.
• Mounting (Optional): Option for wall mounting with screw holes or adhesive backing.
• Internal Antenna: PCB antenna for better WiFi range within the home.
• Access Ports: A small access port for USB charging and maintenance.

Functional

• Data Reporting Interval: Configurable reporting interval (e.g., every 5 minutes, 10 minutes) to balance battery life and data frequency.
• Low Battery Alert: Sends an MQTT message when the battery level falls below a certain threshold.
• Temperature Range: Measures temperature from -20°C to +60°C.
• Humidity Range: Measures humidity from 0% to 100% relative humidity.
• OTA Updates: Supports Over-the-Air (OTA) firmware updates to improve functionality without physical access.
• Reconnection Logic: Automatically attempts to reconnect to WiFi and MQTT broker in case of network loss.
• Local Data Storage: Stores data temporarily in case of WiFi disconnection and uploads when the connection is restored.