Hi,
I´m not sure what you are asking for.
If you know the voltage and the current, then just use Ohm´s law.
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I don´t know exactly where in the schematic and how you want to use those current limiters.
I agree with FvM... I don´t expect much benefit regading UART, I2C, display, IO....
None of the signal lines normally carry high current. All below 1mA.
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I see a lot of vague informations. Nothing we can focus on.
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Basically for battery operated systems:
* reduce idle current (no floating pins, disabling unused circuit / periferals. Using suitable switch mode supply circuits)
* reduce active time (fast wake up, using sleep modes wherever possible)
Klaus