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Inter Integrated Circuit

Is a serial bus to connect Microcontroller and transmit information between chips.

Notes

  • Connect with SDA, SCL (clock) and GND (Ground)
  • Signaling
    • Line is "1" by default, hence the pull-up
    • Writes are done by grounding the line: set as "0"
  • Require a pull-up Resistor on each line
    • Values
      • "Generally 10 kΩ works"
      • 1 kΩ for 3.3v circuits
        • Will waste 1mW of power
      • 10 kΩ for 5v circuits
    • Why
      • Too small value will prevent the IC to pull-down to "0"
      • Too big value will prevent to charge the bus capacitance back to "1"
      • 329

Reference