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Nick Alexeev
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Is there a correct resistance value for I2C pull-up resistors  ?

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JonathanD
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Is there a correct resistance value for pull-up resistors ?

The datasheet of the 24LC256 EEPROM states that:

The SDA bus requires a pull-up resistor to VCC (typical 10 kΩ for 100 kHz, 2 kΩ for 400 kHz and 1 MHz).

I thought that any resistor with a kΩ value would do the job (and it seems that my EEPROM works fine at different frequencies with a 10 kΩ resistor).

My questions are:

  • is there a correct value for pull-up resistors ?
  • is there a law/rule to determine this value ?
  • how do different resistance values affect the I²C data bus ?