We utilize the internal reference voltage when applying the AD7623. According the datasheet of AD7623, the internal reference voltage is 2.048V, which is produced by the 1.2 V voltage of REFBUFIN pin.
However, during the test, we test the voltage of REFBUFIN pin is 1.1489V and the voltage of REF pin is 1.864 V, which have a big difference with characteristic of datasheet. Addition, the datasheet only has a typical value of internal reference voltage.
So, is the situation of the introduced above reasonable?