Hi,
I am designing a PCB where I will be connecting several temperature sensors TMP175-Q1 using I2C interface to the MCU. I have three questions in regards to this:
1) I have read that the maximum number of devices that can be connected with I2C is 128, however, on the datasheet of the temperature sensor I read this "TMP175-Q1 device allows up to 27 devices on one bus" does this mean that I can connect a maximum of 27 temperature sensor with I2C?
2) I also know that the maximum bus capacitance with I2C is 400pF, I know that the temperature sensor has an input of 3pF, do you know how I can calculate the bus capacitance of the tracks? so that I will be able to know the maximum number of temperature that I can use.
3) The length of the I2C connection will roughly be around 3m, do you know if this is a problem or whether the I2C can work fine with that length?
Thanks in advance,
Regards,
Giorgio