When I simulate the AD8624 with a 500 Ohm load resistor, the output is limited to 0.4V.
The circuit is a differential amplifier with gain 1 using 10kOhm resistors plus a 500Ohm load.
The design will have only +/-5 supply voltage.
I have attached a PSPICE netlist.
I found it's necessary to rise the supply voltage to +/-6.5V to get +/-2V output voltage with a 500Ohm load.
Is the mdodel wrong or can't deliver the AD8624 +/-2V with a 500Ohm load when using a +/-5V supply?
Unfortunately there is no specification or typical curve about max. output voltage versus load current.