The MAX31865 RTD-to-Digital Converter Module is a high-accuracy temperature measurement interface designed for PT100 and PT1000 RTD sensors. Based on the MAX31865 IC from Analog Devices (formerly Maxim Integrated), this module converts resistance from platinum RTD sensors into precise digital temperature readings via SPI communication.

Supporting both 3.3V and 5V operation, this module is ideal for industrial temperature monitoring, laboratory instruments, automation systems, and embedded electronics projects requiring stable and accurate temperature sensing.

Features

• Supports PT100 and PT1000 RTD sensors
• High-precision 24-bit ADC conversion
• Wide operating voltage: 3.3V – 5V
• SPI digital interface
• Built-in fault detection (open/short circuit detection)
• Selectable 2-wire, 3-wire, or 4-wire RTD configuration
• High noise immunity with 50Hz / 60Hz filtering
• Accurate temperature measurement over wide range
• Compact and easy-to-integrate PCB module
• Compatible with Arduino, ESP32, STM32 and other microcontrollers

Specifications

• Converter IC: MAX31865
• Sensor Compatibility: PT100 / PT1000 RTD
• Interface: SPI
• ADC Resolution: 15-bit (internal 24-bit delta-sigma ADC)
• Operating Voltage: 3.3V – 5V DC
• Supported Wiring: 2-wire / 3-wire / 4-wire
• Temperature Range (Sensor Dependent):
  • PT100: Approx. –200°C to +850°C
  • PT1000: Approx. –200°C to +850°C
• Noise Rejection: 50Hz / 60Hz selectable filter
• Application Type: RTD Temperature Measurement Module

Applications

• Industrial temperature monitoring
• Process control systems
• Laboratory measurement equipment
• HVAC systems
• Embedded temperature logging systems
• Arduino / ESP32 temperature projects
• Automation and IoT temperature sensing