MAX31865 Platinum RTD Temperature Sensor
The max31865 temperature sensor allows you to use your max31865 RTD
temperature sensor (datasheet) with ESPHome

Adafruit_As the communication with the MAX31865 is done using SPI, you need to have an spi bus in your configuration with both miso_pin and mosi_pin set.
- VINconnects to 5V (- 3V3will output 3.3V), or directly connect- 3V3to 3.3V
- 3Vois not used by ESPHome
- GNDconnects to ground
- CLKconnects to the SPI clk_pin
- SDOconnects to the SPI miso_pin
- SDIconnects to the SPI mosi_pin
- CSconnects to a free GPIO pin
- RDYis not used by ESPHome
# Example configuration entry
spi:
  miso_pin: D0
  mosi_pin: D1
  clk_pin: D2
sensor:
  - platform: max31865
    name: "Living Room Temperature"
    cs_pin: D3
    reference_resistance: 430 Ω
    rtd_nominal_resistance: 100 ΩConfiguration variables
- cs_pin (Required, Pin Schema): The Chip Select pin of the SPI interface.
- update_interval (Optional, Time): The interval to check the sensor. Defaults to 60s.
- reference_resistance (Required, float): Reference resistor on the PCB. Adafruit’s PT100 (#3328) uses 430 Ω, their PT1000 (#3648) uses 4300 Ω.
- rtd_nominal_resistance (Required, float): Nominal resistance of the RTD at 0°C. PT100 is 100 Ω, PT1000 is 1000 Ω.
- mains_filter (Optional, string): The mains power frequency to reject (50 Hzor60 Hz). Defaults to60 Hz.
- rtd_wires (Optional, int): The number of RTD wires. Be sure to solder board jumpers to match! Defaults to 4.
- spi_id (Optional, ID): Manually specify the ID of the SPI Component if you want to use multiple SPI buses.
- All other options from Sensor.