SMBUS / I2C on same bus?

[andrewgillham]

We're using the K60 in out design and talking to a number of other ICs. I understand that it has two ports capable of both I2C and SMBUS communications. Is is possible to use both kinds of device on one bus or are we better off separating them out into one bus for I2C and one of SMBUS?

Also is it necessary / advisable to use a buffer (e.g. TCA4311A) when taking the bus off board, such as to talk to a SBS enabled battery?

Thanks,

Andrew.

[apanecatl]

Hi Andrew, since SMBUS works over I2C, theoretically you could have both of them in the same bus, however you must take into consideration if there is the chance of having both transmitting/receiving at the same time, if you are planning to use only one comm module for both of them or one for each one, my personal recommendation would be to keep them in separate lines.

It is not necessary to use a buffer, the communication can be direct but it is advisable to do so, ultimately is a personal choice but the devices should communicate safely without a buffer.