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I2C Digital Filter use case

Associate III

Hello Community,

I am planning to use I2C operating at 1kHz maximum on STM32G4 & STM32G0 series for measuring temperature from Digital Temperature sensors placed at 2m distance from the main board in an industrial environment using CAT6 (STP) Cables with SCL & SDA paired with Grounds. I have options to operate this I2C bus at 3.3V or at 5V. The Temperature sensor has an inbulit hysteresis of 600mV.

  1. I want to understand the use & any feedback based on experince of the community members on the I2C Digital Filters
    (I can set the I2C-CLK to 4Mhz & then configure the Coefficient of the Digital filter to a value of 10-15 to maximimize the glitch filtering)
  2. Can I simply interface a 5V I2C bus signal directly to the MCU pins (assuming 5V tolerant inputs)? I will be using TVS diodes on I2C connectors on the PCB for ESD & EFT protection.

We will be measuring temperature less frequently (probably once every one hour) & I2C based temperature sensing shall never be initiated at the starting or wake up time of the MCU from any state.

Kindly guide with your experience based insights.