What is the max currant on the -V-ref on pin 23 and 35
These are the -VREF pins.
As these are intended to be used for sensor ground, the current the pins normally see is what the +VREF supplies. But the pins are designed to cope with higher currents in order to withstand short circuits.
Continuous currents up to 8 A should be safe for avoiding damage, but could be problematic for sensor readings if you have this amount of current and also ground sensors via the -VREF.
Customer support service by UserEcho