I have a I2C bus, driven by micro, with 3 components on bus. All are currently 3.3V parts, but availability issues is forcing a change to a 5V sensor for one of the parts. Can i keep the 2 remaining 3.3V parts on the A side of the TCA951 while connecting new 5V I2C part on B side?
Hi Tim,
Yes the TCA9517 can be used to facilitate communication between 3.3-V and 5-V I2C devices. If you don't need buffering (i.e., if the signals don't need to be re-driven in order to overcome a higher level of capacitive loading), then you could consider a switch-base ddevice like PCA9306 as well.
By the way, we've developed a tool for finding level translation solutions based on I2C master/slave device characteristics. You can find the "I2C Designer" tool here:
For more information on I2C buffers, you may want to reference this application note:
http://www.ti.com/lit/an/scpa054/scpa054.pdf
Please let us know if you have further questions.
Regards,
Max
