[FAQ] Can I connect two unidirectional channels on digital isolators to achieve a bidirectional channel for I2C communication?

No, connecting two unidirectional channels in opposite directions back-to-back will not yield a bidirectional channel. If an isolated I2C device is directly replaced by a digital isolator, the digital isolator would latch to a single state and become unresponsive. External components are necessary to implement an isolated I2C bus using digital isolators. For more information on how to implement isolated I2C with a standard digital isolator see the app note: Designing a reinforced isolated I2C bus interface by using digital isolators. Additionally, this E2E thread goes into more details as to why a digital isolator will latch to a single state when used without external components in a bidirectional I2C application.