I have some questions for your AD7891.
When we use by standby mode for AD7891,
1)Does REFOUT(2.5V) stop, when AD7891 doesnt convert for a long time?
2)If we do the soft-standby mode, then REFOUT stop the 2.5V output, correct?
If so, after AD7891 start the A/D convertion, then REFOUT start to output 2.5V correct?
3)No matter what the /STANDBY pin is pulled up to high by external pull-up resister,
after we make change that put 1 on SWSTBY, is your AD7891 changed to standby-mode?
4)We are watching 2.5V output during AD7891 is standby mode also.
When it is the standby mode, REFOUT seems to become no-control action.
I cannot catch these on your datasheet well.