When using the I2C bus protocol, the designer must ensure that the hardware complies with the I2C standard. This application report describes the I2C protocol and provides guidelines on debugging a missing acknowledgment, selecting the pullup resistors, or meeting the maximum capacitance load of an I2C bus. A conflict occurs if devices sharing the I2C bus have the same slave address. This paper provides solutions to this conflict by using the devices’ features or external components.