What happens if the I2C bus is idle for a long period of time?
AD7294
Not Recommended for New Designs
The AD7294 contains all the functions required for general-purpose monitoring and control of current, voltage, and temperature integrated into a single...
Datasheet
AD7294 on Analog.com
What happens if the I2C bus is idle for a long period of time?
When the AD7294 is in command mode it expects the conversion result to be read back from the Result Register within 5ms. If the I2C bus is "frozen" for longer than this then the AD7294 will abort the command mode operation and revert to an idle state, as if the write to the command register had not taken place. It is possible to disable this 5ms timeout by powering-down the temperature sensor in the power down register.
When the AD7294 is in command mode it expects the conversion result to be read back from the Result Register within 5ms. If the I2C bus is "frozen" for longer than this then the AD7294 will abort the command mode operation and revert to an idle state, as if the write to the command register had not taken place. It is possible to disable this 5ms timeout by powering-down the temperature sensor in the power down register.