I have a question regarding the AD7794 datasheet. On page 23 there is a table of channel select bits. For an input of 1000, the channel is states as AIN1(-)/AIN1(-). This will always be zero, so I wondered whether it is correct, or whether it should read AIN1(-) /GND. Please could you clarify?
The AD7794 datasheet is correct. This channel is an internal short. It is useful for debugging. If e.g. you have noise issues with your system, we sometimes suggest that you use this internal short for debug. This helps to locate the noise source.