The default drive mode of I2C pins is open drain - drive low, if I2C is not used the state of SCL/SDA is High-Z (with big input impedance) which is easy to couple noise from the outside to inside,
Thanks. That right.
If the reason is only external noise, I would like to put pull-down to the I2C pins at the view point power consumption.
Is it OK?
Pull down is good, just don't leave SDA/SCL pin float is fine.
Thank you very much.