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HDC1080: Multiple connection on I2C line

Part Number: HDC1080


It is  described that "a read/write operation with incorrect I2C address returns a NACK after the I2C address" on the datasheet page 10.

Does it mean that multiple connection doesn't allow?

Or is multiple connection possible because the device which have the correct address returns ACK?

Best Regards,


  • Dear Kuramochi-san,
    I confirm that it is possible to use the HDC1080 in combination with other devices on the same I2C bus.
    In fact the SDA and SCL lines of the HDC1080 are open-drain, so when another device on the bus is addressed, even if the HDC1080 returns an NACK, it is the device that has the correct address that takes possession of the bus, returning the ACK.
    Instead it is not possible to connect more than one HDC1080 on the same bus, because it is not possible to modify the slave address of the device.
    Please let me know if this replies to your question.
    Best regards,