Orin Nano I2C pin VOL and IOL


On Orin Nano Datasheet Section 4.3 Digital Logic, the Pin DC characteristic is given.
For open drain output low voltage, the following parameters are given.

I have couple questions about this.

  1. Is the VDD in the table the pull-up voltage (3.3V) or the power rail on the pin mux? (vddio_ao = 1.8V for I2C0 and I2C1)
  2. Is the IOL governed by the pull-up resistance and pull up voltage? For example, for I2C1 the rail is 3.3V and pull-up resistance is 2.2kR , and thus the current is ~1.5mA?
  3. For I2C0, the note here says the pull-up resistance is 2.2kR. However in other documents (pinmux, design guide) the resistance is marked as 1.5kR. In this case will IOH be 3.3V / 1500R = 2.2mA and how will this affect max VOL?
  4. What is the max IOL the pin can tolerate?

[Update according to latest guideline]

  1. The VDD is the internal power rail for I2C pins, which is 1.2V or 1.8V.

  2. IOL is controlled by internal drive setting.

  3. IOL is controlled by internal drive setting, not by external pull-up.

  4. IOL could be 3.3mA or more, but basically it is set to up to 3.3mA only for safety.

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